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Maps, plates, charts, etc., may be filmed at different reduction ratios. Those too ierge to be entirely included in one exposure are filmed beginning in the upper left hand corner, left to right and top to bottom, as many frames as required. The following diegrams illustrate the method: Les cartes, planches, tableaux, etc., peuvent dtre fiimAs A des taux de reduction diffirents. Lorsque le document est trop grand pour 6tre reproduit en un seul clich6, il est film* d partir de I'angle supArieur gauche, de gauche A droite, et de haut en bas, en prenant le nombre d'images nAcessaire. Les diagrammes suivants illustrent la mithode. 1 2 3 1 2 3 4 5 6 ,!«■ ^pwjpi^ ., • *''''^^mimmmmmmmiW''mmmmmmmmmmimmtmmmmm j/jf' / . Self-Consciousness . V. Sensations as Objects VI. I erception CHAPTER III. THEORIES OF PERCEPTION. • I. General Description nn.l Classification 11. Descartes III. Locke . IV. Berkeley V. Hume . VI. Reid . VII. Kant . VI J I. Modern KnglisJi Psychology I'AOR 1 6 17 3fJ 44 47 5!) 71 77 86 93 103 116 125 131 vHi roSThWrs. CIIAI'TKK IV. llh'l'llKSh'NTATIOX. 1. (Junditioii ul' |{i'|nv»i;iitiitioii II. LavvB of Hepresentiitiuii .... III. Kind.s of Ueprcsi'iitatioii : riuvnliisy, Mciuory Expectation ..... IV. Imagination in Sciti^pe and Art V. Ima<.;ination in pjthics and Ucligion . VI. IVculiaritifs of Ileprosentation . VII. Ilfprcsontation of Abstractions . I'AdK MS 179 183 180 CHAPTER Y. ELAliOHATlOS OF KNOWLEDGE. I. Predication ...... II. Intuition ..... III. Dc'peudeucc of Predication Uj)on Intuition IV. Tlie Class ; the Concept ; tlie Name . V. Predication again .... VJ. Reasoning!; Simulating Inference VII. Inference ..... VIII. Dctermininjj; Ground of Inlerence IX. The Form of Inference X. Evidence ; Induction ; Deduction XI. Conclusion ..... 190 200 200 209 221 234 240 251 204 208 283 THE ELEMENTS or Till PSYCHOLOGY OF COGNITION. CHAPTER I. INTRODUCTION. Section I. SOURCES AND ARRANGEMENT. § 1. The Psychology of Cognition forms an im- portant part of the philosophy of the human mind, cognition being one of the three great classes of phenomena which, according to the generally accepted division, constitute the mind. The remaining two classes may be designated the Feelings and the Voluntary Activities. These, however, will not come under our special con- sideration, except in so far as they are involved in the first class of phenomena. Cognition is a general name which we may apply to all those mental states in which there is made known in con- sciousness either some affection or activity of the mind itself, or some external quality or object. The CHAP. I. SECT. I. Classifica- tion and character of cog- nition. THE ELEMENTS OF THE i I (MAr. I. SKCT. I. J\'(( (leliKil St pnraiitiii of in< iilol /iheiionieiiK I OKKI hh: ^ciirccx of ill) ini)i(J. CdllUciOHS- I'IniKicdl ortjunism. Psychology of Cognition analyses knowledge into its primary elements, and seeks to ascertain the nature and laws of the processes through which all our knowledge passes in progressing from its simplest to its most elaborate condition. It is necessary for (=cientific purposes to classify mental phenomena, but it must be borne in mind that in actual con- sciousness there is no possibility of separating the I one from the other, and it is frequently difficult to I determine to what class a particular phenomenon belongs. In the earliest or simplest stage of know- ledge it is perhaps difficult to say whether the phe- nomenon should be classed as a Feeling or a Cogni- tion ; and, consequently, it will be necessary in this treatise to consider all those primary elements, of wliatevcr character, which enter as constituent parts into our matured knowledge. § 2. The materials which we shall require in the systematic exposition of our subject are drawn from various sources, but especially the following : — a. Examination and analysis of consciousness. This is the power which every individual possesses of becoming aware of the various feelings and other phenomena which are experienced in his mind. It is the only power by which these phenomena can be directly known or studied, and, consequently, in every system of philosophy it must be appealed to as an authoritative revelation of mental facts. h. The anatomy and pliysiology of the physical organism. Without entering into disputed questions, it is universally admitted that the powers of the PSYCHOLOGY OF COGNITION. \c into its 10 nature li all our mplest to :ssary for enomena, itiial con- atiiig the ifficult to 3uomenon of know- L' the phe- a Cogni- ry in this iments, of ent parts e in the awn from iousness. possesses nd other incl. It a can be . in every as an [physical pestions, of the CItAl'. I. SLCT. I. nimd are in some way connected with, and depend upon, the faculties of the body, and more especially that the nervous system, with its centre in the traniilia of the brain and its extremities scattered over the surface of the body, is the principal medium of communication with the external world. Whatever may be the value which a knowledge of the laws and operations of this system of nerves possesses, it may cast some light upon the more relined operations of the mind itself. c. The history of the human progress or of the lu.. 1. SECT. 1. 2. Analysis of preseiit- ative knoidedye. and com- hinatwii of elemctili* into com- plex pro- ducts. 3. liepre- sentation of mental phtno- memi. nisnsaRPiffismis" 6 THE ELEMENTS OF THE CHAV. I. SECT. 1. -I. FJaho- nifioii- of Inioidechje. These subjects, and certain problems involved in them, form an interesting chapter in the study of the human mind. § 6. The last and highest class of phenomena to which we shall require to turn our attention consists of those complex processes of comparison, generalisa- tion, and inference which are employed in the en- largement and elaboration of our knowledge. The I study of the products of these processes is the work j of the logician. Logic has to do with the results of the mental processes to which we are referring ; I but psychology is concerned with the nature of the I processes tLomselves as revealed in consciousness. i While, therefore, the objects of our study here will, to a certain extent, coincide with those of the j logician, we shall look upon them from a different point of view. It will be our aim to discover the nature and laws of our mental activity exerted in I the formation of those predications, general notions, and inferences which form the subject-matter of logic. CIIAl'. I. SECT. II. Section II. CRTTICISM OF SOURCES. § 7. In this section it is proposed to examine briefly the sources of our knowledge of the mind, for the purpose of ascertaining the kind and amount of evidence which they are likely to give of the mind's processes. These sources we have already arranged into three classes — consciousness, the study of the PSYCHOLOGY OF COGNITION. C'HA!'. I. SECT. II. Stud 1 1 I if COIIijll' •>• ■VH'Ufdl product". physical organism, and the results which express tlie mind's activity. Befjinniiii' with the third of these, as beinsr the most familiar to those who have not devoted mucli attention to the subject, we may remark that from it we need not expect to obtain much assistance in | the study of the more ultimate and elementary phenomena of the human mind. The manifest re- sults of human activity, as seen in language, iu mythology, in art, or in religion, are the expression or effects of mental processes of a complex and elaborate kind. They cannot, therefore, throw much light upon the mental problems connected with the ; first beginnings of knowledge ; but they will assist ; very materially iu showing how the more complex mental operations are carried on, how the simpler elements of knowledge are combined and elaborated, i Leaving their consideration, therefore, for a future period, we may examine more carefully the other two sources which we have indicated. j § 8. A study of the physical organism is without doubt an important preparation for the study of the , mind. But the value of the information which it gives has been differently estimated by different students. All are willing to admit that the connec- ' rh/smd tion between the body — and especially the nervous dl'nrtnt system — on the one hand, and the mind on the other, is of a very intimate kind ; and all should, therefore, agree that the study of the one is an important condition of a complete knowledge of the other. But there are diversities of opinion as to the nature rtf us of its rrJation to th. mind. 8 THE ELEMENTS OF THE CHAP. I. SECT. II. (\.)Minda function oj brain. f of the conri action between the movements of the nervous system and brain which are distinctly phy- sical, and the elementary phenomena accompany- ing or following them which are distinctly mental. The following are clearly distinguished doctrines upon the subject : — (1.) It is held by some that the mind is a function of the brain. In order to understand this, we must bear in mind the relation between function and organ in the vegetable and animal kingdoms. An organ is a constituent part of an organised body which has some definite duty or function to perform. The function of the leg of an animal is to walk or run ; that of the wing of a bird is to beat the air so as to enable the bird to fly. The stomach is a large internal organ of the body, whose function is to contain the food which we swallow until it has been prepared for being taken into the blood. The liver is another organ, whose function is to secrete bile, which is poured into the stomach to assist in the digestion of our food. Every organ has got some special work or function to perform in the body to which it belongs. In the same way, it is argued, the brain has a function to perform in the animal system, and that is to produce the various mental phenomena of which we are conscious. And, acting upon this hasty and crude hypothesis, a set of visionary speculators called phrenologists have thought that they could learn all about the mind, its character, and its laws, by the study of its organ, the brain.* ♦ This is the theory also of M. Comte, G. H. Lewes, and others, PSYCHOLOGY OF COGNITION. its of the [ictly phy- jcompany- ly mental, doctrines a function }, we must ction and loms. An lised body ;o perform. walk or the air so 1 is a large tion is to has been The liver Crete bile, ist in the ^ot some le body to rgued, the al system, henomena upon this visionary ught that haracter, brain.* aud others, There are many objections to this hypothesis which might be referred to ; but in the mean time we shall point out only one, which, however, will be sufficient to set it aside for the present. The functions of all the organs with which we are acquainted are perceived by us either as some material product or some mode of motion. We are able to examine both the organ and the function as ordinary physical phenomena ; both the organ and the function are made known by perception through the senses. But in the case of the brain, the organ is indeed capable of being examined as we examine any other physical organ — by external observation aided by the employment of the dissecting knife. And if we consider the brain as the centre of nervous force by which the muscles of the body are made to contract, we are able to perceive a function of the brain in its result — ordinary muscular motion. But mental phenomena are directly perceived only by consciousness, and are entirely different in kind from any of the functions of physical organs with which we are acquainted. Hence there is a strong presumption, which may be confirmed as we advance, against the hypothesis that the relation between the nervous system and the phenomena of the mind is identical with that be- tween ordinary physical organs and their functions. Consequently, although a knowledge of the nervous who give prominence to the study of physiology as a means of becoming acquainted with mental laws. CHAP. I. SECT. II. lO THE ELEMENTS OF THE CHAV. I. HECT. II. (2.) Millll (tnd Ixtdij two inch- pcmlent nuhntatices. system may bo of importance to tlie study of mind, we can attach to it at present but a subordinate degree of importance. (2.) A second theory of the relation between the mind and the body may be described in the follow- ing manner. The mind and the body are two entirely different substances possessing entirely different qmilities. The mind has been brought into connection with the body, inhabits the body, and uses tlie body as its instrument of carrying out its purposes and communicating with the ex- ternal world ; but they are in nature so entirely different, that there is, and can be, no truly causal connection between the phenomena of the one and those of the other. An impression upon an organ is only an occasion on which, by some mysterious power, a sensation is produced in the mind. So the occurrence of a volition or determination in the mind is only an occasion on which, by divine in- terference, a movement is excited in some of the muscles of the body. The connection between the mind and body is only accidental, and might have been otherwise. The one is now inhabiting and employing the other, but has an existence really independent of the other; and our knowledge of the one cannot be increased to any material extent by a study of the other. Those who hold a theory such as this attach very little importance to the study of the brain and nervous system as subordinate to psychology. It is a degradation to the mind to suppose that any light can be thrown upon its :i ? ■A PSYCnOLOGY OF COGXJTIOX. II workings by a study of its humble habitation and instriment. Consciousness, therefore, and conscious- ness alone should be resorted to by the student of psychology. A theory such as this was held by the older followers of Descartes and the older adherents of the Scottish philosophical school. But there are certain considerations which will prevent us from adopting it as an hypothesis to guide us in our studies. In the first place, the student of psychology has nothing to do with the so-called s%ibstances of mind or matter ; he has to study only the phenomena, the sensations and the qualities which consciousness and perception make known to him. And, again, it is unscientific to advance to the study of the mind with certain preformed and crude notions regarding its nature, its independence of matter, and other things. As far as our experience goes, the mind is most intimately connected with our physical or- ganism, and it appears to bo the duty of the psychologist to take into account every fact bearing upon his subject, admitted to exist, and learn as much from it as possible. Moreover, it lies within his sphere to study only those phenomena which manifest themselves in our present conditions of existence, and not to speculate or make assertions regarding what might be under other conditions. (3.) A third theory respecting the connection between physical and mental phenomena regards I them as simple antecedents and consequents, without [predicating anything concerning the differences in CUAl'. I. SECT. It and cert;- ■ hral cve.ntit ' form two I partiallij co-ordinate 12 THE ELEMENTS OF THE CHAP. I. SECT. II. iferies whone re- lations are not accu- rately known. their nature except in so far as may be learned from actual observation. A certain physical movement or nervous vibration takes place ; it is followed by a sensation. A certain volition is determined in the mind ; it is followed by a muscular movement. The psychologist, aided by the physiologist, may legiti- mately endeavour to discover what particular phenomena of a physical kind always precede or follow certain phenomena of a mental kind, in what order the two series of phenomena occur, and other facts regarding them of a similar kind. But on the other hand, it is not legitimate to assume, without satisfactory reasons, that every mental phenomenon has a physical or nervous antecedent, any more than it is legitimate to take for granted that every organic action is the result of some conscious mental antecedent. As physiologists tell us about certain organic actions which take place in the body alto- gether independent of any mental determination, so there is an a priori probability that there are mental activities which are not connected with any par- ticular physical movements ; and in consequence of this presumption, those who assert the contrary are bound to support their assertions by the evidence of observed facts. The burden of proof falls upon them. This third theory of the concomitance of the physical and the mental series of phenomena is the one which appears to us nearest the truth as far as we know it. It asserts nothing regarding the relations of mind and matter except what is psYcnoLoar of cognition. 13 Ifrom ement dby a in the ,. The legiti- rticular ;ede or in what id other t on the without lomenon ore than ' organic I mental ; certain idy alto- lation, so e mental any par- aence of trary are [dence of Us upon of the kmena is truth as [egarding what is discovered or inferred from actual observation ; nothing regarding the possible independence of wliat are actually united. It must be limited, however, to those phenomena in each series which are dis- tinctly shown to have a connection of antecedence or consequence with phenomena of the otlier series. It is illegitimate to assume that because a certain number of facts in the two series are concomitants, therefore all are so. And from the analogy of the physical phenomena there is a strong presumption that there are facts of a mental kind which have no special physical antecedents. § 9. We come now to refer to that source of knowledge regarding the mind which, though last in order of consideration, is first in importance. It is by consciousness only that we can become directly acquainted with mental phenomena. As those phenomena are called physical which can be per- ceived by the senses either alone or aided by arti- ficial contrivances such as the microscope, so those phenomena are called mental which manifest them- selves in consciousness. Since, therefore, conscious- ness is the only means by which we can become directly cognisant of mental phenomena, it follows that the study of the facts revealed in consciousness must always be the principal method of obtaining psychological knowledge. This study, however, as it is one of great importance, is also one of great difficulty. The art of reflecting upon our own mental operations is one which requires a great deal of attention and cultivation in order to become a CHAl'. I. bKLT. II. C(mscioH»- ness. r^ 14 ciiAr. I. HECT. II. t Mi'thnd of KtuihfiiKj jthenoiuena of con- gciousnesi*. TJIl'J KIKMESTH OF THE proficient in it. This depends partly npon the fact that the energies of human beings are first, and usually continue to be, directed outwards to other persons and external objects. It requires an eftbrt to turn the attention inwards to tlie facts of con- sciousness ; and hence in Greece men had attained to a high state of civilization, and acquired a great deal of knowledge regarding extcinal objects, before any attempt was made to examine and analyse tlie phenomena of the mind. Another cause of the difiiculty of refiection is the great complexity of the phenomena made known in consciousness. This complexity is twofold. In the first place, phenomena are complex from the fact of a great many of them occurring simultaneously or in immediate succession ; and it is diiVicult to separate them the one from the other, so as to ascertain their mutual relations. And in the second place, certain mental actions which seem at first view to be quite simple are in reality very complex in their origin. It is frequently a matter of great difficulty and delicacy to analyse the history of the mind's ability to perform such actions. We are apt to suppose that, because we can perform them easily and readily now, we were always able to do so ; and it is difficult to conceive the condition of our minds when we had not our present ability. § 10. As the chief object of psychology is to ascer- tain the simple and original elements of our complex mental phenomena, and the laws in accordance with which these elements combine and transform VSYCIIOLOGY OF COGNITroX. tho fact rst, and U) other lu eftbrt of con- attained a f^reat s, before iilyse the on is the mown ill . In the fact of a sly or in separate ain their , certain be quite ir origin, ilty and I's ability |)ose that, lily now, Ifficult to we had I to ascer- I complex Jordan ce ransform < HAT. I. MXT. 11. themselves into our matured mental activitien, tiie first part of the method of i>sychol()n'jicn- gateways of knowledge, as they have been called, by Jatlons!'^^"'' which we know the qualities of the external world. 1 But, in addition to the sensations connected witli j these senses, it has been found necessary to form another class comprehending a variety of sensations clearly distinguislied from the former. This class comprises all the sensations connected with the different parts of the organism with the exception of the five senses. This class and the sensations com- prehended in it have been denominated variously, the vital sense, the organic sense, the sensations of \' j i 24 THE ELEMENTS OF THE \ 1 I i '1 U I' ii ] CHAI'. HKCT. II. II. organic life, &c. A clear view of the great variety of sensations of which we are conscious may be obtained by the study of the following table : — 1 oS cc I. Of Organic Life. . II. Of Intellectual Life. Connected with the muscles, bones, tendons, «&c. 2. Connected with the nervous system. 3. Connected with the circulation and nutrition. 4. Connected with the general state of organs, as heat, &c. 5. Connected with the respiration. 6. Connected with the digestion. 1. Organico-Intellcctual ^"- '^"'^^^• jrt. Sn \h. Ta 2. Intellectual. aate. 0. Touch. d. Hearing. \ e. Sight. I. From a glance at the parts of the organism referred to in this class, it will be readily apparent what sensations are indicated. The organs con- cerned in muscular exertion give rise to different sensations when in a state of repose, when active, when fatigued, and when resting after labour. The nervous system may suffer excitement or depression in various degrees or manners, and give rise to a variety of sensations. Hunger, thirst and their opposites, with the sensations connected with them, depend upon certain states of nutrition and circula- tion. From a general condition of the body, which cannot be very clearly defined, there arise feelings of languor or the opposite, and also heat and cold ; the sensations of the latter kind being, however, chiefly felt in the skin. The respiratory system is the seat of a class of sensations such as that of suffocation, and there are sensations also connected PSYCHOLOGY OF COGNITIOX. 25 \ with the digestive organs. The geueml character- istics of these sensations are that they arise in theN oi-ganism itself as the concomitants of vital opera- tions, and that they are accompaniments, results, or stimulants of action, not elements of knowledge. II. The sensations of intellectual life are those whose chief end appears to bo the imparting of knowledge regarding external things. Two of these senses are so closely connected with the respiratory and digestive systems, and give us comparatively so little extra organic knowledge, that their sensations occupy a middle "position between those of the first class and those of the more in- tellectual sense which we have placed last in order. The sense of smell, placed at the portal of the respiratory . organs, gives notice of the entrance of any noxious vapour into the lungs, and occasions the sensation of smell when any odorous emanations come into contact with the olfactory nerves. " The sense of taste is that by which we distinguish the sa]^id properties of bodies. The term, as commonly understood, includes much more than this ; being usually employed to designate the whole of that knowledge of the qualities of a body (except such as is purely tactile) which we derive through tlie sensory apparatus situated within the mouth. But this is dependent upon the assistance of the olfactive sense, which is affected by the odorous emanations of all such bodies as are capable of giving them off; and the indications of which are so combined with those of the true questative sense as to (HAP. 11. SE( T. n. \ •* J SemcA of Kmill and Utstc. f , y i i i). m 26 THE ELEMENTS OF THE d'l i.: !i n rjHAi*. u. SECT. n. make an apparently single impression npon the sensorinm. Moreover, there are certain sensorial impressions received throngh the orgim of taste, which are so nearly allied in their character to those of touch, as to render it difficult to specify any fundamental difference between them ; such are the imngent sensations produced by mustard, pepper, the essential oils, &e., all of which substances, when applied for a sufficient length of time to any part of the cutaneous surface, produce a sensation which can scarcely be distinguished from that excited through the organs of taste, in any other way than by its inferior intensity, and by the absence of the concurrent odorous emanations. The taste of such substances might, therefore, perhaps be considered as the composite result of the impressions made upon the sensorium through a refined and acute touch, and by the effect of their odorous emanations upon the organ of smell."* The sensations both of smell and taste mav be arranged in a loose popular way into subordinate classes ; such as pungent, acrid, sweet, &c. But as no classification having any pretence to scientific accuracy and exhaustiveness has yet been offered, the subject does not demand much of our attention. It may be remarked by the way that there are certain well-defined classes, inasmuch as the sensations of one class, such as the bitter, cannot, by any means of which we are aware, be transformed into those of another. II. We now come to the study of the sensations of * Carpenter, 'Human Physiology,' p. 177. PSYCHOLOGY OF COaxiTTOX. 27 the more intellectual of the special senses — touch, hearing, and sight. And it will be necessary to distinguish carefully between those which are pro- per and original to those senses and those which are acquired. We have seen already that in the case of two of these senses, hearing and sight, the sensation undergoes a process of objectification, being referred to a distance. In the case of touch this is not so obvious, although it is still true to a certain extent. The sensation of pressure, which is in itself purely organic, is referred to something not at any distance, it is true, but still external to the organism. Now, in each of these cases the objectification of the sensation, not being original, must be distinguished from the sensation itself. The sense of Touch has, as its proper organ, the skin, which " is peculiarly adapted for this purpose, not merely by the large amount of sensory nervous fibres which are distributed in its substance, but also by its possession of a papillary apparatus in which these nerves for the most part terminate, or rather commence." The tactual sensation proper is that which is felt when any body slightly comes into contact with the skin so as to make its presence felt. But this tactual sensation is often combined and confounded with others of a different kind. When, for example, the point of the finger is pressed against the table, in addition to the tactual srnsation, there is a feeling of resistance or hardness which is manifestly the sensation of muscular exertion objecti- fied. Where the finger is rubbed over the surface of CHAr. II. >SE( T. n. (Uxtin- (juii'heil from (to- i/ninil Ixniiirh ill r (ioii. Stylise of touch. 'if i w 28 TJIf: ElKMKNTFi OF THE fWKV. II. SKCT. n. Si IMC nj 111 iniiiQ. a roii^li body tlioro is also a t'ombinutiou of the tactual sensation with tliat of muscuhir exertion. The skin is alsotlio principal seat of the sensations of licat and cold, and when an object which differs in toniperaturo from that of our body is brought into contact with it, these sensations are experienced. But aUhougli the nerves of the tactual sensation are suscei)tible also to heat and cold, the two kinds of sensations are essentially unlike. From descriptions of the organ of hearing given by physiologists, we learn that it is a very delicate organ of touch. The object of hearing is sound; and the physical conditions of sound are vibrations of s(jme material body which all'ect the air, and are propagated by it to the ear. The sensations of sound may vary in many ways, according to the nature of the sounds which are heard. The principal characteristics of single sounds are pitch or tone, clearness, volume or quantity. Two or more simultaneous sounds are harmonious or discordant. The pitch or tone of a sound is determined by the number of vibrations of the air whicli strike upon the ear in a second, and by many experiments this has been accurately determined. The other qualities of sound appear to depend to a great extent upon the material and size of the vibrating body. The knowledge of the distance and direction of the body which causes the vibrations of the air is obtained by experience,* and the ability to detect * Of course we must postulate the possession of a suitable organ- ism to render this experience possible. VHYCUOLOdY OF COONITlnS. 29 sliirlit (liflorcuces bet\vo(ni snccossivo sounds and tlio Imrnidiiy or discord of simultanoous ones is also to a certain extent an acqnired power. Wo are eon- cerned at present only with the sensations in tlieir orij^inal simplicity which are marked by clear differ- ences from those of every other sense, and discrimi- nated from one another by many distinctions of pitch, streni^th, clearness, volume, and quality. The projK'r object of the sense of sight is light or colour; and the physical conditions of sensati. H. into fine elastic teetli, and made to revolve ^vitli great feliCT II '. "_ ! rapidity upon an axle. " When tin's wheel is turned at an uniform rate, its teeth, which are at equal distances, strike a bar in passing ; and this regular succession of similar concussions excites a regular succession of similar sensations of sound. Now, while the wheel turns suflSciently slowly, the sensa- tions, being discontinuous, are distinct, and each of them being compound is a sound. But when the Avheel is set to turn fast enough, a neiv sensation arises^ that of a musical note. It distinguishes itself from the remains of the noises which still go on and con- tinue distinct, and stands out as a fact of a different kind ; among the different elementary sensations which make up each sound, there is one which the operation has separated ; and this now ceases to be distinct from the similar elementary sensation follow- ing in each of the succeeding sounds. All these similar sensations now eombine in one long continuous sensation — their mutual limits are effaced ; experience, just as in a chemical analysis, has extracted an elementary sensation from the complex group in which it was included, has joined it to an absolutely similar elementary sensation, and formed a new com- pound — the sensation of musical sound." * Thus it is seen that a particular sensation, that of a musical note, is capable of being resolved into more elementary sensations, each of which is distinctly in consciousness. If we nov/ examine a sensation of liirlit, we shall see that it also is resolvable into more * Taine, ' On Intelligence,' p. lOS. CGI PSYCHOLOGY OF COGNITION. Zl CHAl'. II. SKCT. II. elemciitarv sen.satioiis. The resolution of the sensa- tion is efteeted by the resolution of its most im- portant condition, the rny of li^ht. The prismatic spectrum comprehends a variety of distinct sensa- tions wliich, previous to the analysis, must have been contained in the complex sensation of white light. A well-known optical toy, consisting of a disc of card- paper with the spectral colours painted upon it, and made to revolve rapidly upon its axis, shows that the separate sensations may, by rapidity of succession, become blended together again and form one complex sensation more or less closelv reseniblinir the original one. The proper mixing of colours is an important part of the oil-painter's art, and in this there is a complex sensation produced by the mixing together in proper proportions of the oils, which, taken separately, would produce a simple, or at least a less ! complex, sensation. ■ We thus see that in many cases the sensations of the two most noble senses may be shown to be com- . I posed of more simple elements, being, however, still ! sensations. A similar course of investigation, regard- ! ing the sensations of taste, smell, and of organic life, would probably show that in all these cases there are many complex sensations which are capable of resolution. But it is needless to continue the inves- tigation farther, as we have already sufficiently esta- blished our conclusion, which may be thus stated : — i (1). There are in consciousness sensations of a ! litmU oj complex character, which, as far as consciousness is ! """ ^''*' concerned, appear to be simple. t '1 ^11 m I <•! fl I 1 ^ I i^:r I'i I ii'i 34 THE ELEMENTS OF THE CHAP. II. SKCT. II. 11 ;i (2). Tlie resolution of these complex states of consciousness cannot bo effected by consciousness alone, but by applying the nietliods of pliysical science to the physical conditions of these states of consciousness. (3). Hence, we may conclude the possibility of there being other complex states of consciousness, whicli, by mere reflection, cannot be analysed into their component elements. Aunh/six \ § 17. "VVe now consider the possibility and legiti- .so/<>»s hut maey ot analysing sensatio!is mto elements wkicii "!'"'" / are not, and cannot be, bi'0Uj>:ht within the sphere of ronsiderecl consciousness.* I Suppose that the point of a needle has been 1 made so small that when it is held in a clear light, directly before the eye, it is just visible, and no more. Upon the principle of tlie infinite divisibility of matter, this point maybe divided into two halves, each of which is invisible. Or, suppose that in the wheel of Savart, referred to above, all the teeth ex- ee])t two have been bi'oken off, and the concussion of two teeth upon the bar is necessary to produce an audible sound. If one of these teeth bo broken, the i vibration of the remaining; one will be inaudible. In j both of these cases, and in others which might be mentioned, a certain amount of physical antecedent ' is necessary as a condition of comeious sensation. And * The doctrine of latent mental nK^dification, held by Sir W. Hamilton and others, asserts that undLrlyinjirti<>ii.< it is felt, and felt consciously. Tlierefore, to analyse j sensations into elements of which we cannot bi; con- scious is not len-itimate. (2). There are other possible explanati(»ns (»f tlie ] • ditliculty. It may be that the object from which the j liglit is reflected, or from which the vibration of the | air proceeds, produces such a slight agitation of the { intervening medium that it is spent or di.-persed be- ' foie it reach(.'S tlie organ of sense. Or, suppose the | agitation of the ether or air to reach tlie nerve of sense, it may be th^.t the impression upon tlie nerve ' is so slight, that no vibration is propagated to tlie nerve centre in the brain, or that the vibration is so exceodinirlv slii>ht as not to be a sunicient condition of sensation. And that cither of tlicse suppositions is the true one, appears to bo supported by tho fact that certain artiticial appliances, such as the mi- croscope, collect or intcn-ify the physical conditions of sensation, so that what was before invisible or in- audible may be distinctly seen or heard, 'i'lu! rays of light falling from a point invisible to the naked eye, are collected and condensed by the microscope so as effectually to impress the o[)tic nerve, from which we naturally conclude that, previous to the use , D 2 I ctation. This mental process, it must be borne in mind, as referred to here, is subsidiary to the acquisition of presentative knowledge, as we shall presently see. In the meantime, we are not suppos(Hl to know any- thing except sensations, revived sensations, and the relations which thev bear to one another in kind, in time, and as members of associated groups.* * It is possible that there are some sensations which cannot be revived except as parts of a <>;ronp ; and, perhaps, there an' few which can be recalled by a merely mental effort without the aid of some associated cireiuuatauces. Uut nevertheless it teems allow- ( iiAi'. n. fKCT. ni. liidi jii /«- (hiire itf till iinUi'iif i>i lifdiidliii. i II til m \i i n I I'l h 44 r/Zi; ELEMENTS OF THE CHAP. II. SECT. IV. Itesumif. Lanriimge impiijiiig )it-lj'-censiitious of difierent kinds may be experienced at the same moment. And tlie question is— What is the relation in which these contemporaneous objects of consciousness stand to one anotlier? The followin::,' are clearly dis- tinguished answers to this question: — {a.) The co-existence of sensations at tlie same point of time implies their mutual externality, and therefore involves the idea of extension or space. Several sensations, as of smell, taste, colour, sonnd, may exist altogether, and as they are distingnished from one an(jther in kind, they must appear to be the one idthout the other. And this relation of mutual outness is the simplest form in vvhicli we perceive extension. According to this doctrine, extension or space is a form of our sensations as well as time, and just as original in reference to our knowledge. Tliere is a slight modification, or per- haps an integral part, of this theory, in which it is held that some single sensations, as colour and touch, occupy space, or are diffused over an extended space. Whether the one or the other, or both of these opinions be held, it is manifest that their liolders look upon space as an original form of sensation, and perceived intuitively in the same way as time.* (h.) In opposition to the above theory it is held that all mental phenomena are unextended, and that the possession of extension is the essential characteiistic which distinguishes physical from mental objects. * For a full expositioa and (kfcucc of tbid theory, sec § 30. CHAI'. IT. SIX'T. V . Iiifuitici' till (try ()/ extent>iuu. (Objection cunfti- tntiiKj (I gen f ml thi.ory. ^l\ so THE ELEMENTS OF THE CHAP. II. SKCT. V. A priori iheorif of f.riciiiiion. A sensation, therefore, as an object of consciousness, cannot possibly occupy extension or place. And since an individual sensation does not exist in space, it is impossible that the relation between two or more contemporaneous sensations can be a spatial relation. To speak of the mutual externality of sensations is, therefore, to attribute to sensations a mode of ex- istence which they do not possess. Sensations differ in kind, and they succeed or co-exist with one another in time, and the attributing to them of any- other relation would destroy their character as mental phenomena. § 28. Those who hold the second of the preceding views regarding sensation must in some way account for the origin of our conception of extension. Sensa- tions, the primary objects of consciousness, are not themselves extended, but we evidently possess a notion of extension which we must have got in some way. How has it been attained ? The answers to this question divide themselves into two classes : — (a.) Some maintain that extension is an original principle of our constitution which springs into con- sciousness upon the occasion of some sensation taking place. The sensation, althougli not itself extended, suggests extension by a law of our nature. Exten- sion is thus an a 'priori but latent conception which rises up into consciousness upon the occasion of a certain experience, but is not the result of that ex- perience. Now, it is evident that the placing of any conception amongst a priori principles simply amounts to a confession of inability to explain it PSYCTIOLOGT OF COGNITION. 51 CHAI'. 11. SECT. V. otherwise. Inexplieability is an important character- istic of all conceptions believed to be a priori. But before admitting any notion to be inexplicable, we are in duty bound to examine any attempt which has been made to explain it. The following attempt is the most important. Q}.) It is held by J. S. Mill and others that the | Mim-le- notion of extension is the product 01 muscular sensa- //,f,„.,/. tions differing in intensity and duration. " Suppose," says Mr. Mill, " two small bodies, A and B, suflfi- ciently near together to admit of their being touched simultaneously, one with the right hand, the other with the left. Here are two tactual sensations which are simultaneous, just as a sensation of colour and one of odour might be ; and this makes us cognise the two objects of touch as both existing at once. The question then is, wliat have we in our minds when we represent to ourselves the relation between these two objects, already known to be simultaneous, in the form of Extension or intervening Space — a rela- tion which we do not supjiose to exist between the colour and the odour ?" (3ur answer to this is, " that whatever the notion of extension may be, we acquire it by passing our hand or some other organ of touch in a longitudinal direction from A to B ; that this process, as far as we are conscious of it, consists of a series of varied muscular sensation When we say that there is a space between A and B, we mean that some amount of these muscular sensations must intervene ; and when we say that the space is greater or less, we mean that the series of sensatiorvs E 2 52 THE ELEMENTS OF THE ■\\ i; ■\ ! • MIAP. (amount of muscular effort beings given) is lonj^er or shorter. If another object, 0, is farther off in the same line, we judge its distance to be greater, be- cause, to reach it, the series of muscular sensations must be further prolonged, or else there must be the increase of effort Avhich corresponds to augmented velocity. Now this, which is unquestionably the mode in which we become aivare of extension, is considered by the psychologists in question to he extension. The idea of Extended Body they consider to be that of a variety of resistuig points, existing simultaneously, but which can be perceived by the same tactile organ only successively, at the end of a series of muscular sensations which constitutes their distance; and are said to be at different distances from one another because tlie series of intervening muscular sensations is longer in some cases than in others An intervenini:^ series of muscvdar sensations before the one object can be reached from the other, is the only peculiarity which (according to this theory) distinguishes simultaneity in space from the simultaneity which may exist between a taste and a colour, or a taste and a smell ; and we have no reason for believing that Space or Extension, in itself, is anything different from that which we recog- nise it by."* Here, then, is an attempt to explain extension by one who does not think extension is involved either in single sensations or in the relations of different but simultaneous sensations. Let us examine the attempt : — * Mill, 'Examination of Sir W. Hamilton's Philocophy,' pp. 273-275. psYcnoLoar of cognitton. 53 IS I 1. It is assumed tliat extension is identical with that by which it is recognised or measured, that is, \vith a succession of muscular sensations occupyinp^ time. But this is by no means to bo admitted. The amount of force witli which a ball is expelled iVom the month of a cannon is recognised and measured by its velocity, that is, by the number of feet wliich it traverses in a second of time. But no one ever maintains that force is identical with velocity. In the same way, although extension is measured by muscuhir sensations occupying time, to say that the former is identical with the latter is quite unwarranted. 2. ^Vhy is it that muscular sensations are chosen to fill up the intervening space between one point and another ? All sensations are ex hypothesi equally destitute of extension. The two points, A and B, are recognised by two sensations, and must be assumed not as points in space, but as points in time, because the idea of space is not supposed to be known. Let, then, the point A be marked by a particular sensation, say of smell; a number of intervening sensations, muscular sensations, or any others differ- ing in intensity and duration, take place. Then another point of time, B, is reached, marked by another sensation. Thus, here we have two points, A and B, points in time, and recognised by two distinct sensations, separated from one another by a number of intervening sensations, say of sight, or hearing, or smell, differing in intensity and duration ; is the result of this an idea of extension or space? {'irAi'. II. M:(;r. v. , ;:i \ V!i 54 CHAP. WKCT. II. V. THE ELEMENTS OF THE Certainly not. The mere statement of the problem, substituting^ for "muscular sensations" any other kind of sensations, is sufficient to show the absurdity of deducing the notion of extension from that of sensations succeeding one another in time, 3. The reason why muscular sensations are chosen to fill up the space between the points A and B, instead of sensations of smell, or taste, or colour, appears to be that the former kind of sensations is expressed in motion^ which involves extension, and the points A and B are really points in space. For let us eliminate careCuUy from the data all spatial elements, and see what follows. The sensations by which they are marked are at first supposed to be simultaneous. In this there is only time. But the idea of space is said to be acquired by passing the hand from A to B. Suppose the hand is at A. Here is a sensation in time. B as yet does not exist, because the existence of the point must not be assumed till the sensation indicating it has taken place. The hand leaves A ; the point A ceases to exist, except in memory, because the sensation indicating it has ceased. The hand reaches B; a new sensation takes place, a new point in time, has been reached. But where is A ? In memory. It is a point not now existing, except in past time. To speak, therefore, of two points of time existing simultaneously is altogether unmeaning. And Mr. Mill's explanation is quite unintelligible unless the points are tacitly assumed to exist in space and the muscular sensations to result in motion. Thus, the very ■ i PSYCIIOLOQY OF COQNITION. 55 idea whose origin the theory professes to exphiin is quietly assumed at the beginning of the explanation. § 2!). Tiie preceding theory of extension, called by Mr. Mill the psychological theory, being found untenable, we are driven back to a reconsideration of the view which makes the notion of extension an a priori principle of the mind. According to this theory, the mind possesses in its own structure, as it were, a notion of s})ace, but not a conscious one, and upon a certain experience this notion becomes conscious and is projected upon the object of ex- perience. Now, with reference to tliis view, we confess, in the first place, a strong prejudice against the explanation of a difficulty by some latent or a iwiori mental principle. It simply amounts to a confession that the difficulty cannot be explained, and, moreover, it assumes the existence of a mental principle beyond the sphere of consciousness, which is, in philosophy, a very questionable procedure. And, still farther, our conception of extension is not that of a subjective principle, but rather of an objective condition of things. For these reasons we decline to accept the view in question, although probably there is a certain truth involved in it, and go back to a more careful consideration of the first answer to the question, "What is the relation in which these contemporaneous objects of con- sciousness stand to one another ? " That answer was that "the co-existence of sensations at tlio same point of time implies their mutual externality ; and therefore involves the idea of extension or space." CHAl'. II. f ultstnict whicli fHAi-. n is not ji piirticnliir scnsntion of smell or t.isto or ' toiic'li, or sonio other; unS(3 sensations or to led theiu except ns bein;j^ localised. Sensations ap[)eur to have two sides, or to stand in two relatif foreign origin — that is, modes of the non-ego ; they are localised — that is, they involve extension. l>ut must be borne in mind that it is in their chaiacter as modes of tlie non-ego that objectified sensations are localised. The localising is, therefore, not so much an act of consciousness as a precept of conscious- ness and a form of the non-ego. If it be asked, I- 58 THE ELEMENTS OF THE 111 {'': ' i !iii CHAP. II. SKCT. V. Element)^ of percep- tion. what are the physical conditions which determine that sensitions as modes of the uon-e^o shall be localised ? tliat is a question wliich, from the stand- point of consciousness, we need not and cannot answer. The probability is that the power of localising sensations is born with us — one of our inherited abilities — although in its perfection it is probcibly the result of the education of iiie senses,* § 31. We have now got all the elements necessary to the completion of our knowledge of that nearest and most complex portion of the material world, the organism. Given sensations, the objects of con- sciousness, of different kinds and localised in different places ; and given the power of moving the arms and, by touch, interfering with or producing localised sensations, and we can easily understand how our knowledge of the organic non-ego is gradually filled up. Muscular sensations con- tinued for a longer or shorter time, or differing in intensity, are now of real service. They enable us to measure that extension which has been otherwise made known. The whole complicated organism mav be considered as one sense whose intention is, first, to lireaent to consciousness objects possessing extension, and second, to make known by a complex process the existence and nature of external things. This process we shall consider in our next section, * See Taiue, ' On Inklligence,' p. 314. PSYCHOLOGY OF COGNITION. 59 'I Section VI. rERCErTIOX. § 32. In our analysis of perception ^ve saw that our knowledge of external things may be resolved into certain sensations of different kinds, supposed to be at a distance from us, and united together in objects. Perception thus consists of sensations projected into space, and united together in a permanent group, supposed to have an existence independent of the mind which perceives. In the synthetical con- struction of cur knowledge we have already studied sensations as objects to consciousness, and learned what is involved in them. We have already attained the knowledge of extension as the form of the non-ego immediately presented to consciousness ; and we have seen that this non-ego constitutes that complicated physical organism by means of which more remote objects are brought to our knowledge. We have now to trace the education of tliis com- plicated sense, the process by which it enables us to perceive distant objects and their qualities. § 33. The sensations which chiefly make known to us the existence of objects outside of our bodies are doubtless that of touch and the muscular sensa- tion. In the exercise of the muscles, portions of the body are brought into contact with some objects outside of them which excite sensations of touch and resist muscular effort. The sensations of touch and CHAP. II. SECT. VI. Eexviiic'. Seumticm II Nil iluaUlij. \ ■»! 6o THE ELEMENTS OF THE i I I h I m s V ■' It I P If cuAr. ir. sKcr. VI. ]-Hi.*cular t'flort appear to have one object, and the resistance wliieli it offers reveals its externality to tlie pliysical organ and independence of it. Thus there is produced within us the belief of the exist- ence of some object of touch without us ; and as that object opposes a greater or less amount of resistance to muscular pressure, we think of it as having a power to resist pressure — that is, as being hard and solid. Thus hardness is just the correlative of muscular force, the sensation of muscular exertion projected outside of our bodies and attributed to some external objects. But that which, in the organism, was a sensation, when thought of as without, is called a quality. Sensation and quality are thought of as having a twofold relation ; the one with reference to knowledge, the other ^ith leference to existence. In the first reference, sensation is the sign which suggests to us the quality ; in the second, the quality is thought of as the cause which produces the sensation. The muscular sensation is connected also with motion of the limbs of the body, and when this motion is coinbined with the tactual sensation, there is made known to us the smoothness, roughness, or other superficial qualities of the bodies which we touch ; and, as a matter of course, the extension which we saw was involved in the diffusion or the m\itual externality of localised sensations accom- panies those sensations when projected outside of us, and thus we think of the hard or soft, rough or smooth objects of touch as being extended and figured. Hence we see that touch and its closely as PSYCHOLOGY OF COGNITION. 6i connected muscular sensations are very in;iportant means of augmenting oar knowledge, carrying us away beyond ourselves into surrounding space and revealing a world of wonderful objects, l^ut as far as we have gone, these objects are known to us only as correlatives of our tactual and muscular sensations invested with extension. We must now bring into requisition another sense, and see how the revelations of siii-ht are combined with those of touch. § 3-1. It must be borne in mind that the knowledge primarily given in sensations of sight has for its object only a ceitaiu organic condition, and the colour which we see is really within us. But it is equally certain that colours cq^pear to be at a distance from u>j, and consequently must have undergone a process of j^rojection out into space; and we are now to inquire how this proce.- has taken place, or, in other words, how the eye has been educated. We have already seen that touch brings to our knowledge txternal resisting bodies ; and we shall see that this sense is the great educator of the eye, teaching it to clothe those bodies with the colours whi(di appear in consciousness through the medium of the eye. It has been laid down as a law, '' That a sensation appears to us to be situated at the spot in which we are accustomed to meet with its usual cause or condi- tion, and this spot is the one at which the explorations of touch are capable, by acting there, of checking or modifviu": the commenced sensation."* A coloured object, for example, is placed within easy reach of a * Taint", ' Ou IntLlligencr,' p. oil. CIIAI'. II. SI XT. VI. J'lUiJi'ctidJl of ColuHlx hi/ (l. e perceive the colour as at a distance from us, it is still a thing known to us. But besides this colour as hnoivii, we think of some cause or power existing beyond or behind the piqjected sen- sation which, striking upon our eye, has produced the sensation. This cause or power cannot be a sensation ; it is supposed to exist anterior to and independent of our sensation. It cannot be an object of knowledge, because it can be known only as a sensation, but, ex hypothesis it has an existence anterior to sensation. Tlius, the non-ego appears to consist of two elements ; an element uhicli is known, and an element which is unknown, but supposed to i i to I? ^■ 1 1 PSYCTIOLOaY OF COGNITION. 65 ciiAr. II. SKLT. VI. QHiiVdij ambiijiionx. exist. The known element, we have seen, consists simply of projected sensations ; the nnknown ch.Muent is composed ol" something \\liiL'h, when brought into relation with our senses, hel[)s to produce sensations. The term qualitij lias nnfortunately become am- . biguous by being apjilied to botli of these elements. ! \Vhen it is said that tlie quality of an object is one ! of its characters by wliicli it is known to us, it is evidently a projected sensation, for all objects as | known consist of such. Wiien it is said that the i quality t)f an object is that which produces a certain ' sensation in us, it is api)lied to something wliicli, ! apart from tlie sensation, is unknown. Tlie former of the two applications of tlie word quality appears t(j us the most natural, and by quality we siiall, therefore, henceibrth indicate those characteristics of objects whicli constitute our actual knowledge of them. There is, however, a still farther restriction to the term quality, or at least an important dis- ; tiuction between two kinds of qualities. The quali- ties of colour, smell, hardness, &c., are simply sen- sations of sight, smell, muscular effort, d'c, ideally transferred or projected into external space. But the space into which these sensations arc projected, or \\hich they occupy, is not a sensation of any kind. Although in our knowledge it is insei)arably con- nected with sensation, it is essentially different from sensation. To adopt scholastic distinctions, it is the form of which sensation is the matter, the nuantitu 1 ./'""*/'"•'" of which sensation is the quality. It is therefore ' I'^t'j- perhaps improper to speak of extension, figure, and I F Quality dinliii- i uuishid '' ■! 1 I- 66 THE KLEMENTS OF THE Ih u .' i. rllAI'. SKCT. 11. VI. uthor forms of space as being qualities at all. They are rather the spatial relations of qualities, the objeetive form into which sensations, being projected, are known as qualities. This essential distinction between the form of sensation and sensation itself has given rise to the distinction between primary and secondary qualities, the former comprising different modes of space, and the latter qualities properly so called, that is projected sensations. Taking quality in the latter, that is, in its proper sense, there is another distinction, although not an essential one, which may be observed. The mode of operation of the different senses is somewhat different. In touch there is neces.sariiy a contact between the external object and the organism ; in sight, hearing, and smell, the necessitv of similar contact is not so obvious. Consequently touch has been supposed by some to bring us into contact with objects as they really exist ; other senses not. Hence the distinction! of some qualities being supposed to be more essen- tial to the idea of body than others, or of some being purely subjective, while others are partly or wholly objective. Perhaps such distinctions have arisen also from the fact that, in some of the senses — for example, sight and hearing — there is obviously a perception of distance, or a projection of the sensa- tion ; while in others, as smell, there is not so much, or so clearly so. Whatever may have given rise to such distinctions, they are fallacious. All qualities properly so called are originally sensations and subjective. All sensations come to be objectified, rsYcnoLoay of ronxir/'hw (>7 ond involve elements belonginpj to the non-ego. All sensations, except purely organic ones, are projected ideally beyond the organism, and there known as qualities; while purely organic sensations, that is, sensations which are discovered not to depend upon extra-organic conditions, are not thouglit of as qualities at all. Consequently the only essential difference between qxudituis of objects arises from the difference between the hinds of sensations.* Other dilferences are either fallacious or accidental. § 37. Having considered the constituent elements of objects as known to us, that is, as consisting of real or ideal sensations projected into space and forming there a unity, let us now give some atten- tion to the supposed unhiown non-ego. AVhen we perceive a colour, we think of some unknown cause or jiower which, coming into contact with our eye, gives rise to the sensation. So every otlier quality of objects suggests to us the existence of something behind it and beyond it which, in relation to our organism, gives rise to different sensations. What- ever this is, it is and must be in itself unknown, because when it comes within the sphere of our knowledge it is already transformed into some sen- I sation or other mode of consciousness, and when we attempt even to conceive it, it must be conceived under the form of some mode of consciousness. Let { us, for clearness, call this unknown something x. ' Tliere is then supposed to be an x corresponding to every different quality which we perceive. And we ' * For another distinotion, see § 179. j F 2 tllAl'. II. SKlT. VI. Xvhi('h we are conscious ? These are some of the questions which may be proposed in connection with this subject, and we refer to them here, chiefly for the purpose of setting them aside. They are not questions which it is the business of the psychologist to answer. In so far as they can be answered, they belong to the s[)here of experimental physics or of metaphysics: in so far as tliey are insoluble, they should be left alone altogether. As far as psychology is concerned, we are confined to the analysis and synthesis of our conscious knowledge ; and in perception the object of our knowledge is the scnsiUe world — that is, the world revealed to us througli our senses. Out- side, or behind this sensible world, we cannot go, either in perception or in imagination.* The un- known X of sensible qualities is not only incapable of being perceived, but also as x of being conceived. And as in psychology we are concerned only with what can be know n, questions regarding tlie unknown are referred to only to point them out as irrelevant. § 38. We are now in a position to understand u7dd>iict I t'learly what w'e mean by the dject of percep- ofpercci)- . ^JQjj_ From what we have seen, it is manifest that turn. ' * We may, however, aa we shall afterwards see, by inference. tj psyriroLoav of conxirrnx. perception is tlio act only of educated senses. And those who identify perception with consciousness must mean by it somotliim^ different from what is usually meant by the word. Tlie o!)ject of i)ereeption must be at a greater or less distance from the sentient or jxiints of riiir. ill luo'lern times, and speci'jilly since the time of Desciirtes, that wo iiiid the original cliaos of human knowledge becoming separated into cltMirly defined .sciences. We shall tlierefore look f.>r tlie theories of ])ereeptio\i,, which we wish to examine only in the history of modern philosophy, from the time of Descarte^;, as in tliat period we ar(3 likely to find the clearest statements of the results of investigation into the nature of our knowledge of external things. Before proceeding to examine any of the parti- cular theories which have been held regarding per- ception, we propose to take a general view of certain fundamental differences between these theories, by means of which we mav arrange tliem into classes. The possil.ulity of making a cias.^ification assumes, of course, a knowledge more (n- less complete of th(; things to be classified, and the reader must there- fore take for granted the accui-a^'v of oui- general descriptions until he is able to verify them by the study of the special theories to \Nhich they may be applied. § 40. There are two distinct points of view from whi.'h the student of the process of perception may proceed in the examination of his knowledge. It is difiljuit to find any single unambiguous word which indicates these jjoints of view respectively, and therefore, without in the meantime naming them, we shall proceed to describe them at length. (1) From the first stand-point, the psychologist regards the objects of the world of sense as having an existence independent of the mind ; and the ( rSYCnoLOGY OF COGMTIuX. \ plienonieiiji of tlio iiiiiiil as liaviiiir an existence independent of material (tbjeets. The trees, and stones, and otlier o])j'"'ts wliieh we Jr the sake of distinctness, and for want of a lictter name, we may call this the stand-])oint of jn'actical daalism. (2) Those who adopt the second point of view assume notliing regarding the existence or nature of an external world, but analyse all their knowledge into its original elements, as found in consciousness: and, beginning with the simplest facts given in / .•) ' IIA)-. Ml. SKl'T. 1. ii i •! H \ , ! •4\ i 'n ti' V i li ,1 t 74 (HAP. rii. SECT. I. Origin of n'prt>«rH !a- THE ELEMEXTF^ OF THE consciousness, seek to discover the manner in which the sphere of our knowledge and belief is gradually filled up. As a preliminary to the adoption of this method, it is necessary that nearly all our naturally acquired beliefs regarding the existence and nature of objects of sense should, for the time, be given up. The object of tlie psychologist is to determine the origin and process of the acquisition of knowledge, and, therefore, it is not legitimate to assume any- thing regarding the existence and nature of the objects of knowledge 'mtil it is seen how tlieij have hecome ohjecfs. From this, which we may call the 2)hiIosophical point of view, the student works Lis way from within outwards, beginning with those facts of consciousness, which, as far as he can discover, are elementary, endeavouring to discover what they reveal of tlie non-ego, and how they are combined or modified, and in no case assuming anything which they do not give. One or other of these points of departure has been adopted, and adhered to with greater or less consistency, by nearly all modern philosophers. We siiall not at present express any opinion as to their respective merits, but proceed to examine the theories of perception which may be classed under them respectively. § 41. We have said that the problem which the psychologists who adopt the first method require to solve is, to determine how two independently exist- ing and heterogeneous substances c;.n have commu- nication the one with the other. Given, that there 6 rsYcnoLouY of coaMTioy. 75 exists a mind, spiritiuil and unextendrd; tliut out- side, in space, there exist material bodies possessing various qualities ; how does tlie former come to ' know or believe in the latter? The answers to this question have been various, and at present we shall not attempt any exact classiiieation of them, as, indeed, perhaps no classification could be made wiliiout in some way doing violence to the theories ' concerned. Generally speaking it has been held that mind can have no immedidte knowledge of matter, and that knowledge can onlv be effected bv i the intermediation of some image or idea, which ! eith^T" represents or suggests the external object. I The i;i:a(amental principle which appears to under-! lie the most of the theories of this kind is that the i mind cannot directly know anything but its own ; ideas, and consequently these theories have been classed together under such names as idealism, i represented ive idealism, cosmothetie idealism, cl'c. But I it is to be borne in mind that injustice may easily be ■ done to theories by forcing them into some particular ! classification because some common form of language j is employed in them, without Civreful consideration of the real meaning of the language and of other essential principles which the theories comprehend. ! § 42. Amongst those who study the process of perception from the second, which wo called the philosophical, stand-point there are important . differences. They all begin by giving up the posi- tion of practical dualism whiedi is the result of the ordinary education of the organism through which cuAr. III. SKIT. 1. n ...■*(■ phtCHi lUithod. J ) S dil i '' m liii $' 76 CHAP. HI. SKCT. I. T/ff'J ELEMENTS OF THE ov(!ry 0110 luisscs. They analyse tlie ()l»jeets of tlie senses into materials given in eonsciousness, and endeavour to ascertain tliose tacts ot* consci(^iisness which are irreducible to others more simple. Taking up their position, thus, at the origin of knowledge, they work their way outwards, tracing the process by Which knowledge is gradually acquired. The [principal differences which exist between different theories of this class arise from the different views which are taken regai'ding the nature and significance of the facts revealed in consciousness. As in the previous class we hesitated to attempt giving a more minute classitication of the tlieories contain*. :^ in it for fear of doing injustice to some of them, so now it will be as well to postpone minuter description until wf! have examined the important tlieories which assume this stand-point. Our general divi- sion of theories of perception into two great classes has been instituted chiefly for the purpose of furnishing a sort of key to the understanding of the tlieories to be passed in review. AVe shall not examine all the theories of each class in immediate succession, but shall rather take them in the historical order of their appearance, ])eing thus better able to perceive their relations to one another. of le lot rsYCiiOLonY of cognitios. Section II. I> E S C A 11 T E S. §4)1. ])L'scartes Ix'gnii his pliilosopliisiiig by re- solving to doubt tlie truth of all j)ro})ositiou8 rcfeivcd at second-hand. Ho found liinisolf ablo to doubt the existenco of the world, of God, of his own boily, of everythinir, in short, except doubt itself. Ihit doubt is only a form of thought, and hence, according to Descartes, the act of thinldng itself, as given in con- sciousness, was the one certain foundation of all know- ledfje. But the assertion of thinking involves the assertion of a thinking being ; cogito ergo sum. Thinking, in its widest sense, is the essence of mind. Having thus established a firm foundation on which to build the superstructure of his system, Descartes ju'oceeded to prove tlie,existenceof (rod. According to him, " When the mind reviews the different ideas that are in it, it discovers what is by far the chief among them — that of a Being omniscient, ail power- ful, and iibsolutely perfect; audit observes that in this idea tliere is contained not only possible and fontinirent existence, as in the ideas of all other things which it "learly perceives, but exist'Miec ab- solutely necessary and external so from its perceiving necessary and external cxisteneo to be compristd in the idea which it has of an all-[)erfect Being, it ongiit manifestly to conclude that this all- perfect Being exists." * * ' Piiucipkd,' part i., xiv. ciiAr. m. SKCT, M, I>('^iii'h»h,ijii I of perception. He reasons thus : " It cannot be iiiii'i. ' doubted tliat every perception we have comes to us from some object different from our mind ; for it is not in our power to cause ourselves to experience one perception rather than another, the i)erception being entirely dependent on the o]>ject which affects our senses. It may, indeed, be matter of i inquiry whether that object be God, or something I different from God ; but because we perceive, or j rather, stimulated by sense, clearly and distinctly j apprehend, certain matter extended in length, breadth, and thickness, the various parts of which ! have different ii<:j:ures and motions, and irive rise to ' the sensations we have of colours, smells, pain, t\:c., God would, witliout question, deserve to be regarded I as a deceiver, if he directly and of himself presented to our mind the idea of this extended matter, or merely caused it to be presented to us by some object which possessed neither extension, figure, nor motion. For we clearly conceive this matter as entirely distinct from God, and from ourselves, or our mind ; and appear even clearly to discern that the idea of it is formed in Ua on occasion of objects existing out of our rjinds, to which it is in every respect similar. IJat since God camiot deceive us, for this is repugnant to His nature, as has been already remarked, we must unhesitatingly conclude I PS YCIIOL (J Y OF C GNJ TION. 79 tliat there exists a certain object, exteii'led in leng'tli, breadth, and thickness, and possessing all tliose pro- perties which we clearly apprehend to Ixdong to what is extended. And. this extended substance is what we call body or matter." * § 41. From these extracts, and from other parts of his writinirs which need not be cited, we mav draw out what appear to bo the essential principles of Descartes' psychology. (a). He begins his investigations by starting from what we have called the philosophical stand-point, assuming nothing but the existence of thuihuKj as his foundation. Then from the nature of certain ideas which constitute his conscious thinking, he infers the existence of an all-perfect and veracious Being. (h). Consciousness reveals to us also certain other ideas which are (1) beyond our power to create or annihilate (2) ideas of extended substance giving rise to certain sensations, and (3) occasioned by ohjeds different from God, and existing outside of our minds which they (the ideas) rejn'esoit. must ciiAr. 111. SKCT. n. (^'). hey powi be produced in us by (ilod. But since we clearly apprehend the idea of extended substance, and since God would not deceive us, it follows that this extended substance must exist outside of us. (cZ). As the essential ([uality of mind is tliinlinf/, so the essential (piality of material objects is eKteimon ; otL er qu ■ilities, such as hardn(!ss, (Colour, lic, beini Sjl'^ii iiKlfv xtntiiiii lit iif /-''■•••- 'a/7( >■' (If": (liiK ■<. 1 ; I'l iri variabl-j, and, therefore, accidental. Principles,' i)art ii., i. ophprs use the word j CarUsinn idea to indicate some object of thought which is dis- , iiif.a. "'^" tinct from the activity of the mind in perceiving or ! G 2 '. i: ill IMAGE EVALUATION TEST TARGET (MT-3) // 1.0 I.I *a|||||M 112.5 : 142 mil 2.0 1.8 |l.25 1.4 1.6 ^ 6" - ► %' V} m /: m J^ '> J^f y V /A Photographic Sciences Corporation 23 WEST MAIN STREET WEBSTER, NY. 14580 (716) 872-4503 ,\ ;V •N? :\ \ '^^ o^ % c?- */. ^ \ ^ ^ i II ,. I i I '. ! / 1 V i ! I '! -'^4 I'MAr. s:-;cT. 111. II. THE ELEMENTS OF THE tliinking it, and which appears to Iiave attributed to it an independent existence. For example, Descartes says :* " Further, I cannot doubt but that there is in me a certain passive facuhy of perception, that is, of receiving and taking hnoidedge of the ideas of sen- sible things ; but this would be useless to me if there did not also exist in me, or in some other thing, another active facidty capahle of forming and ^oro- ducing those ideas.'* And he soon concludes that the active power of producing these ideas is in corporeal objects. The cardinal doctrine of Malebranche's psycho- logy is that ideas of material objects can be directly perceived only by the mind of God ; but since we exist in Him, we participate in His knowledge and perceive His ideas. Thus, in Cartesianisni the idea is a distinct entity, contained in some mind either Divine or human, and existing quite independently of the mental activity involved in the perception of it. But a careful analysis of consciousness might have led these philosophers to the conclusion that the distinction between the act of thinking and that which is thought, the act of perceiving and the percept, the act of conceiving and the concept, is only a logical one. Any conscious activity of the mind is on one side an act, on the other side an object or idea ; the act is the idea, the idea is the act, but viewed in another relation. The greatest confusion in psychology lias arisen from the use in different senses and for different jDurposes of the word idea ; and it is necessary now either tp banish * • Meditationoe,' vi. PSYCHOLOGY OF COGNITION. «5 CHAT. 111. si;ir. II. the word altogether from use, or to employ it in a clearly defined meaning. In the meantime, it should be noted that all mental phenomena are obji'cts of eoi seionsness, and cannot exist apart from the con- sciousness in which they are apprehended. And to speak of ideas as if they could pass from objects to the mind, or as if one mind could be conscious of the ideas of anotljer, is either an abuse of language or the illegitimate attribution of independent existence to an abstraction. This error of Cartesianism long continued to cause confus^ion in psychology, but it is now long since it was perceived and abandoned. j § 48. The philosopiiy of Spinoza (1632-1677) was, | Spimr.a in a sense, the result of Cartesianism. The chief differences between the doctrines of Spinoza and Descartes had reference not to the psychological process of knowledge, with which only we are now concerned, but to the nature of the real existence which underlies all phenomena. Descartes had postulated the existence of two substances, thought and extension, as the necessary constituents of mind and matter ; but it appeared to Spinoza that thought and extension are both themselves i>henomena, and cannot therefore be the suhstances in whicli other phenomena inhere. Descartes' psychological analysis had discovered only those attributes which were found to be essential to the mind and material body respec- tively ; but Spinoza thought that all attributes must have a substance in which they inhere, and rejecting the dualism which had hitherto prevailed, he asserted that thought and extension are attributes M m ■;i ' : . J ii^ 1 i'i^ : li i ' \ i 'r I ■\f ' Hi-iW v\ ^\ *ii| M / I I h. . i ,1 . ■i ^i 86 CHAP. III. SECT. III. Jjuclte's principle. THE ELEMENTS OF THE of one common substance which underlies them both. There is thus only one substance, self-existent, in- finite, and eternal ; and that substance is God. The qualities, however, of mind and matter are 'pheno- menally distinct, so that, as in Descartes, there can be no direct causal or cognitive relation between them. But both are phenomena of one substance ; there is a correspondence between them. The thought corresponds to the thing ; the idea to the object. To enter into any detailed examination of Spinoza's pantheistic Ontology would take us altogether aside from our subject. The only important correction which he made in the Cartesian psychology was the assertion that thought and extension, being only essential attributes, cannot be considered as sub- stances. We shall now leave Descartes and his followers for the present, and give our attention to the beginning of another philosophical movement in England. Section III. LOCKE. § 49. Locke, in bis psychology, begins with the principle that there is nothing in the mind except what comes into it from without ; it is like a sheet of white paper, upon which experience writes our ideas. The experience which gives us our ideas is of two kinds, sensation and reflection. By the former, we perceive the qualities of bodies ; by the latter, the PSYCHOLOGY OF COOXITIOX S7 CHAP. III. SECT. III. ideas we have derived from sense are variously modified, repeated, or combined. Our ideas are thus either simple or complex. "But it is not in the power of the most exalted wit, or enlarged under- standing, by any quickness or variety of thought, to invent or frame one new simi)lo idea in tlie mind, not taken in by the ways before-mentioned ; nor can any force of the undei'standing destroy those that are there."* There are some ideas, such as those of colours or sounds, which gain admittance to the mind through one sense specially adapted for them. There are other ideas, such as of space or extension, which con- vey themselves into the mind by more senses than one. Wliatever the mind perceives in itself, or is the immediate object of perception, thought, or under- standing, Locke calls idea ; and the power to produce any idea in the mind he calls quality of the subject wherein that power is. Qualities are of two kinds; First, those which are utterly inseparable from the conception of body, such as solidity, exten- sion, figure, &c. ; and Second, those whicli are nothing '^ Secomlanj in the objects themselves, but powers to produce | various sensations in us by their primary qualities. Bodies produce ideas in us ; in the case of primary qualities, by impulse, and in the case of secondary qualities, by the operation of insensible particles on our senses. " The ideas of primary qualities of bodies are resemblances of them, and their patterns do really exist in the bodies themselves ; but the * ' Essay,' bk. ii., ch. ii., § 2. Primari/ (lualitit*. qualit l*:s. ;. k .-»i . i ' lit i J! i I T ff 88 THE ELEMENTS OF THE ih ^1 i Hi: i ;i|: 1 i ' ( ■1(1 i 1 ! I cirAP. in. SECT. in. ic « Loch (lorfn'iii's hrhjlll itated. ideas produced in us by the secondary qualities have no resemblance of them at all."* Perception is the first and simplest idea we liave from reflection upon sensations. Before perception can take place, there must be some idea imprinted by sense upon the mind ; but in perception the ideas of sensations are often changed by the judgment. § 50. In the preceding paragraph we have given, pretty much in Locke's own language, the most important of his doctrines regarding perception. We si I all now endeavour to present in more systematic form his solution of the cliief psyclio- logical problems, pointing out those which he has not attempted. (1.) He appears to assume that the mind is notliing but a capacity of receiving sensations or ideas from experience. In this he differs from Descartes, who cannot doubt the existence of his mind as a thinking being independent of everything material. The prin- ciple of Locke and his school is : There is nothing in the intellect hut ivhat comes hito it through sense ; by Leibnitz, a distinguished follower of Descartes and opponent of Locke, this principle is amended by the addition, except intellect itself. (2.) The psychological problem which Locke at- tempts to solve is not, how there arises in conscious- ness the knowledge of an extended non-ego, hut how the sensitive organism assumed to exist conveys to the mind ideas of more distant objects. Locke thus begins from the stand-point of practical dualism. ♦ * Easay,' bk. ii., oh. viii., § 15. PSYCHOLOGY OF COGNITION. 89 (3.) The mind knows tlie exterx^dl workl by means of ideas, some of which resemble the qualities which exist in bodies, while others do not. And in this reference Locke is guilty of the same error which we find amongst the Cartesians ; the idea is evidently taought to be something different from the activity of the mind in thinking it. Locke's psychology may, therefore, be described as one of representative idealism of the crudest kind. (4.) The primary qualities of bodies are the only real qualities which they possess. The secondary qualities are only 2>oit'ers to produce certain itleas, as of colour, sound, &c., in us, but these powers are possessed and exercised ht/ the lirimary qualities. § 51. With reference to the first position of Locke, that there is nothing in the mind except what comes into it through sense, we may remark that it has occasioned an important and long- continued controversy amongst philosophers. Leib- nitz, the ablest contemporary critic of Locke's philosophy, pointed out that there must be a mind possessicg a certain structure or constitution in 1 order to render experience possible. And although Locke may be correct in saying that there are no | innate ideas anterior to experience, yet the nature of certain elements of our knowledge is such that they could not be derived simply from experience. There are certain propositions which are characterised by self-evidence and necessity — that is, the truth of which we perceive intuitively and cannot possibly deny. As an example of these propositions we may cnAr. III. SIXT. III. Locke s principle conU utid h,j Lvil- nits. K. >. \l' \ i. ri i Hi I •Hi I ili I' 90 CHAP. III. SECT. III. Locke asmmes (lualimi. THE ELEMENTS OF THE cite, " Things which are equal to the same thing are equal to one another." This proposition is an ultimate intuition ; it cannot be proved by anything more simple ; it cannot be denied, because its opposite is inconceivable. It is argued, therefore, by those who differ from Locke, that the necessity of such a proposition could not originate in experience, since experience can only give what is, not what must be ; and, consequently, that there must be some- thing in the constitution of the mind which imparts the character of necessity to certain axiomatic propositions. § 52. Locke sets out with the resolution to trace the origin of our knowledge, and supposes that the mind at the beginning is destitute of all ideas. The most simple ideas are introduced into the mind through sense — that is, through an organ of our physical hodies ; and, still farther, the ingress of the idea through sense is accounted for by some impulse of the primary qualities of external bodies. Thus there is assumed the existence of organs of sense and external bodies, and the problem is to show how the latter, by means of the former, transmit ideas of themselves into the vacant mind. Now there can be no question that this position of Locke is the one which the majority of men naturally occupy. There is in cliildren and savages a complete practical knowledge of objects around them and of their own bodies, although there is a complete ignorance of what is meant by such words as mind, or sensation, or consciousness. In the historical acquisition of rSYCIIOLOOY OF COGNITION. l;»owledge, ohjects are perceived before sensations are known in consciousness. Mankind, without reHeetion or conscious thought, assume the stand-point of crude or practical realism, and the great majority of men never leave it. But when one attempts to make a psychological analysis of his knowledge, it is not legitimate to assume objects as existing until it is shown how they become known. § 53. Notwithstanding the implied assumption of the existence of bodies, there is an attempt on the part of Locke to show how the mind knows external objects. This is by means of ideas which come into the mind through the senses. It is ditlicult IVe- quently to say what Locke means by the word idea, on account of the many different senses in which he uses it, and the inextricable confusion with which different senses of the word are interchanged. There is, however, reason to believe that he was \\hat has been since called a representative or hypothetical realist; that he held ideas to be the only things immediately known ; that from the mind's knowledge of ideas it infers the existence of external qualities j and that the ideas of primary qualities really re- semble those qualities, which latter really constitute bodies as they exist. Without undertaking a criticism of some of these positions, which we shall see after- wards is done by others, we may at present point out an important paralogism. The design of the representative hypothesis is to explain how we come to know external objects. These objects, then, are assumed to be in themselves unknown; and their 91 CHAT. in. SECT. ni. Loch's thiory iij idiuis. f! I mi 3 i. |> 7^^ i I 92 OHAl'. in. HKirr. III. ([f gt'cntid- artj (juuli- ties. THE EL FOMENTS OF THE existonoo is iiilerred to acfouiit lor the ('xi^t(nlce of the ideas which are immediately known. 'J'hiis the ideas represent the primary qualities of external objeets to \\w miud. Now supposing- ideas to exist, and supposing: the inference to be admitted that they have some external cause, we may ask, how can it be aflirmed that the idea represents or resembles the inferred quality ? In order to assert that one thinjj; resembles, or does not resemble, another, it is n(^cessary that there should be an independent knowledge of the two thinirs, a comparison between them, and a recognition of their resemblance or non-resemblance. But in this case there can be, ex hypothesi, no inde- pendent knowledge of one of the terms of the comparison. The quality is known only as an infer- ence from the id(3a, and hence nothing can be asserted as to its likeness or unlikeness to the idea. The fact is, psychological analysis, in Locke's time, was only in its infancy, and consequently in his writings there was very great confusion in various respects — a confusion which has been to a very great extent cleared away by subsequent writers. § 54. It is to be noticed that, according to Locke, it is the insensible particles of the primary qualities of bodies which produce in us the ideas of the secondary qualities. The meaning of this appears to be that the resisting substance of a body may become so small as not to excite any sensible tactual sensation, but that still it is capable of excit- ing sensations of sight, smell, or taste. Thus, all ideas are produced by impulse from some extended 1 rsYcnoLooY of cocixiTrox. 93 <'iiAr. III. sK.cr. IV. materiiil sub.stunco ; but, in tlio ctiso of tlie priinary qiialitit'8, thu extension is j)orL't'ivo(l, iiiul, tlu'rct'oro, the idea resembles tlie quality, whereas when the extension bc'conies so small as to be imperceptible, it then gives rise to smells, tastes, and other non- resembling ideas. If this be Lo(;ke's meaning, we naturally ask, how is it that secondary qualities do not exist in bodies? If they are simply primary qualities divided into particles so small as not to offer resistance to pressure, there aj) pears no re-ason for saying that they have no objective existence at all. This is another instance of Locke's confusion. We must now see how Locke's principles were treated by his successors in psychological i esearch. Section IV. BERKELEY (1684-1753). § 55. Wiien we compare the subtlety and clear- BirhUiji^ ness of the mental analysis found in the writings of Bishop Berkeley with the confusion perceptible in Locke, we might fancy that we had advanced at least a century onwards in the history of thought. In Berkeley we have the first English philosopher who obtained a clear insight into the ])roblems of the psychology of perce[)tion. And his S(duti()n of some of these problems has not been improved U[)on to the present day, except, perhaps, in the manner of expression. We shall endeavour to give, as briefly as possible, an outline of the psychological doctrines of which he is the author. ch annus. < i » ^ , i- . % I ' :> ; ■^1 ^^ !' I n I 94 THE ELEMENTS OF THE ! i CHAP. III. hw;t. IV. Neto ihrory of vim'on. 13erkel(iy*s Essay towards a New Theory of Vision was his first publislied philosojjliical work, and may servo us hero as an introduction to Itis system. In it wo havo Bcrkoley's departure from the crude duah'sm of practical life and histlieory of tlie manner in whicli that dualism is established. The following arc the positions which he takes and defends: — " (1.) Distance, or the fact of an interval between two points in the line of vision, — in other words, externality in space, in itself invisible, — is, in all cases in which we appear to see it, only suggested to our imagination by certain visible phenomena and visual sensations, which are its arbitrary signs. " (2.) IVFagnitude, or the external space that objects occupy, is absolutely invisible ; all that we can see is merely a greater or less quantity of colour, and our apparently visual perceptions of real magnitude are interpretations of the tactual meaning of colours and other sensations in the visual organ. " (3.) The situation of objects, or their relation to one another in space, is invisible ; all that we can see is variety in the relations of quantities of colour to one another, our supposed pure vision of actual locality being an interpretation of visual signs. " (4.) There is no sensible object common to sight and touch ; sj)ace or extension, which has the best claim to this character, and which is nominally the object of both, is specifically as well as numerically different in eaeh — externality in space, or distance, being absolutely invisible, while size and situation, ^1 1 ill PSYCHO LOGY OF COOMTloX. jS SKCT. IV, ns visible, have nothing in common witli size and [ chap. hi. situation jis tiinj2;ible. '* (5.) Tliecxphumtion of tlio unity which wc attri- bute to scMisible ti»inji:s, as romplonicnts of visible and tangible qualities of one and ihe same substance, is contained in the theory that visible ideas and visual sensations, arbitrary signs in a Divine Language, are significant of distances and (►f the real sizes and situations of distant things ; while the constant association in nature of the two worlds of vision and touch has" so associated them in our thoughts, that visible and tangible extension are habitually regarded by us as specifically, and even numericallv, one. " (G.) The proper object of Geometry is the kind of Extension given in our tactual experience, and not the kind of Extension given in our visual experience, and neither real planes can be seen — real extension in all its phases being invisible, and colour in its modifications of quantity being the only proper object of sight, while colour, being a pure sensation, cannot exist extra-organically in space." * § 56. The substance of the New TJieorij may be thus expressed: The perception by sight of distance, magnitude, and direction, or of bodies as existing without us and being extended, is not an original but an acquired power. In sight we are conscious only of colour, but as this sensation and various tactual sensations are frequently experienced con- temporaneously, we fancy the object of sight is * Prof. Fraser's anuljsia ia Lis cdilioii of Berkeley. Suhftanr.e of theory. 1^ I > ) 1,1 1.; < i ; \ \ • 1 * < : ' ?' '■ i-- <9 ii 11) . 96 ClIAl". III. t^KCT. IV. ()}>j<('h of laioidcdije. THE ELEMENTS OF THE identical with tlie object of touch. And since it is the tactual qualities of bodies in mIucIi we have the i^reatest practical interest, visible colour and exten- sion soon, by association, become simply signs to call up the tactual qualities of bodies supposed to be more real. There are some points in connection with this theory which may offer matter for criticism hereafter, but, in tlie meantime, we shall take a further view of Berkeley's psychology by quoting from his * Principles of Human Knowledge,' Part I. : — (1.) " It is evident to anyone who takes a survey of the objects of human knowledge, that they are either ideas actually imprinted on the senses ; or else such as are perceived by attending to the passions and operations of the mind ; or, lastly, ideas formed by help of memory and imagination — either compound- ing, dividing, or barely representing those originally perceived in the aforesaid ways. By sight, I have the ideas of light and colours, with their several degrees and variations. By touch, I perceive hard and soft, heat and cold, motions and resistance, and of all these more or less either as to quantity or degree. Smelling furnishes one with odours, the palate with tastes ; and hearing conveys sounds to the mind in all their variety of tone and composition. And as several of these are observed to accompany each other, they come to be marked by one name. Thus, for example, a certain colour, taste, smell, figure, and consistence having been observed to go together, are accounted one distinct thing, signified by the name aj^iyJe. . . . PSYCHOLOGY OF COGMTToX. 97 ruAr. 111. .SECT. IV. K II (Drill 'I tiiiml. (2.) "But besides all that endless variety of ideas or objects of knowledge, there is likewise something whicli knows or perceives them, and exercises divers operations, as willing, imngining, remembering, abont them. This perceiving, active being is what I call , mind, spirit, soul, or myself. By which words 1 do { not denote any one of my ideas, but a thing entirely ' distinct from them, wherein they exist, or, which is the same thing, whereby they are perceived — for the existence of an idea consists in its being perceived. (3.) " That neither our thoughts, nor i)assions, nor Ohjmt.^ ideas, formed by the imagination, exist without the i'„}",.J'/,i'' mind, is what everybody will allow. And to me it '""' ""'v is no less evident that the various sensations or ideas imprinted on the sense, however blended or combined together (that is, whatever objects they compose), cannot exist otherwise than in a mind perceiving , them. I think an intuitive knowledge may be ob- j tained of this by any one that shall attend to what is meant by the term exist when applied to sensible things. The table I write on, I say, exists, that is, I ; see and feel it ; and if I were out of my study 1 1 should say it existed, meaning thereby that if I was , in my study I might perceive it, or that some other j spirit actually does perceive it ! (7.) "From what has been said, it is evident there ; No muftn: is not any other substance than s[iirit, or that which i perceives. .... For an idea to exist in an un- 1 perceiving thing is a manifest contradiction, for to have an idea is all one as to perceive ; that, there- fore, wherein colour, figure, &(:., exist must perceive H ■ I. i; (. 1 .,. . j* if; i f'' ll - i TT^ M t i I ( 1 V 98 TEE ELEMENTS OF THE CHAl'. III. SECT. IV. Distiiic- tion hr- fire(-n (juitJitifiK fnUncionti. them, hence it is clear there can be no unthinking substance or suhstratum of those ideas. (8.) " But, say you, though the ideas themselves do not exist without the mind, yet there may be things like them, whereof they are copies or resemblances, which things exist without the mind in an unthink- ing substance. I answer, an idea can be like nothing but an idea ; a colour or figure can be like nothing but another colour or figure xVgain, I ask, whether those supposed original or external things, of which our ideas are the pictures or representations, be themselves perceivable or no ? If they are, then they are ideas, and we have gained our point ; but if you say they are not, I appeal to any one whether it be sense to assert a colour is like something which is invisible ; hard or soft, like something which is intangible : and so of the rest. (9.) "Some there are who make a distinction betwixt 'primary and secondary qualities. By the former they mean extension, figure, motion, rest, solidity or impenetrability, and number; by the latter they denote all other sensible qualities, as colours, sounds, tastes, and so forth. The ideas we have of these we acknowledge not to be the re- semblances of anything existing without the mind, or unperceived ; but they will have our ideas of the primary qualities to be patterns or images of things which exist without the mind, in an unthinking substance which they call matter. By matter, there- fore, we are to understand an inert, senseless sub- stance, in which extension, figure, and motion do PSYCHOLOGY OF COGNITION. 9'J actually subsist. But it is evident, from what we have already shown, that extension, figure, and motion, are only ideas existing in the mind, and that an idea can be Hke nothing but another idea, and that consequently neither they nor their archetypes canexist in an unperceiving substance. Hence, it is plain that the very notion of what is called matter or corjwrecd stihstance involves a con- tradiction in it (26.) " We perceive a continual succession of ideas, some are anew excited, others are changed or totally disappear. There is therefore some cause of these ideas whereon they depend, and which produces and changes them. That this cause cannot be any quality or idea is clear It must therefore be a substance; but it has been sliown that there is no corporeal or material substance; it remains therefore that the cause of ideas is an incorporeal active substance or Spirit." § 57. We now proceed to point out some things in Berkeleianism worthy of remark. And, in the first place, it must be admitted that Berkeley has not carried his pysehological analysis quite far enough. When he says, " by sight we have ideas of colour &c.," it is plain that he assumes the existence of our sensive organism. And although, according to his theory, the organism is composed, like all other objects, of ideas, yet its existence should not be assumed until it is shown how it is known. There is another defect in Berkeley's analysis which must be admitted. He was not able to H 2 CIIAl'. Til. SKCT. ]V. Sfiirif (hi ul'Jtdirc c(tn.-pace. THE ELEMENTS OF THE surrounding objects, I perceive many visible bodies ; and upon shutting them again, and considering the distance betwixt these bodies, I acquire the idea of extension. As every idea is derived from some impression wliich is exactly similar to it, the impres- sions similar to this idea of extension must either be some sensations derived from the sight, or some internal impressions arising from those sensations." * It is not the latter, therefore it must be the former. "My senses convey to mo only the impressions of coloured points, disposed in a certain manner. Hence we may conclude with certainty that the idea of extension is nothing but a copy of these coloured points and of the manner of their appearance." t Thus Hume concludes that extension is an idea abstracted from particular impressions of sense, the peculiarities of colour, &c., being left out of view, and attention paid only to the disposition of points. "As it is from the disposition of visible and tangible objects we receive the idea of space, so from the succession of ideas and impressions we form the idea of time ; nor is it possible for time alone ever to make its appearance, or be taken notice of by the mind." % ** We have no idea of space or extension but when we regard it is an object of our sight or feeling." So " the indivisible movements of time must be filled with some real object or existence, whose succession forms the duration, and makes it to be conceivable by the mind."§ or * ' Treatise.' bk. I., part II., § 3. t lb. : lb. §Ib. rSYCJIOLOOY OF (JOQNITION. (( As to those imirressionSj which arise from the senses, their ultimate cause is, in my opinion, perfectly inexplicable by human reason, and it will always be impossible to decide with certainty, whether they arise immediately from the object, or are produced by the creative power of the mind, or are derived from the Author of our being." * " The opinion of the continued existence of body depends on the coherence and constancy of certain impressions." t § 61. Having given the important psychological doctrines of Hume in his own language, we now proceed to make such remarks upon them as seem called for. But, before doing so, we shall arrange more systematically the doctrines to which we pro- pose to refer. (1.) All our simple ideas are copies of some im- pressions previously experienced. No idea, therefore, can be found in the mind which has not, more or less proximately, been copied from some impression. (2.) There is no idea in the mind of substance, either corporeal or spiritual, except in so fiir as sub- stance means a collection of qualities or of impressions and ideas. This doctrine follows immediately from the preceding, since siibstance is admitted to be neither a sensation nor the copy of a sensation. (3.) Extension and duration, or space and time, are ideas abstracted from sensations. The idea of ex- tension is a copy of the co-existent points of visible or tactual impressions. The idea of duration is a * ♦ Treatise,' bk. I., part III., § 5. t ' Treatise,' bk. I. part IV. § 2. 107 niAp. m. SECT. V. CilUxr of fihi itiiim ua illlX^ilic- ahh: Ohjictirili/ i\t plained. Dortrinex arratKjed. si;; k I- ■i. ;j Ul 'm 1 08 THE ELEMENTS OF THE \ !•' CHAI'. III. HECT. V. (Criticism. Sl'eptical results. CA)\)y of tho continuity of sensations. I>ut as abstract ideas liavo no existonc(3 independent of tlio conereti; impressions from which they are abstracted, it follows that space and time have no existence independently of extended or contiiniing impressions. (4.) It is impossiWe to infer with certainty tho cause of sensations. The metaphysical hypothesis of an insensible substance as tlio cause of sensations has been shown to be contradictory. And it is like- wise impossible to infer, with IJerkeley, that tho Divine IMind is that cause. (5.) If it bo asked how objects — that is, collections of impressions — appear to have a continued and in- dependent existence, the only answer that can be given is, that tho impressions composing them are seen to have a certain coherency and constancy of rt.'currence which leads the mind to attribute to them independent existence. § 02. Tho first of these principles held by Hume is only a re-statement in more definite form of what, long before, had been held by Locke. But in Hume's hands it became a powerful instrument of destruction. We have no ideas except those that are copies of some antecedent impressions. But matter as a svhstratum is not given in any sen- sation ; neither is mind as the subject of ideas ; neither is causal efBciency, except merely that one impres- sion or idea regularly precedes another ; neither is God. Therefore we have no ideas of matter, or mind, or cause, or God. This ouffht to be Hume's conclu- sion ; but he actually concludes that we cannot psyr/ioLoav of coax/fjox. ICX) < II.M'. III. ,si:t T. V. iiifci' the cxistcnco of those unknown tliinj^s. This ])nnci[)le, drawinjjj with it, as it did, HUeh skoptinil ♦'onchisions, was most important in stimulating lleid and Kant to inquiro into its accuracy. We sliall, tliereforo, leave the criticism of it t(j them, merely pointing it out now as the principle which, by its consequences, led to the greatest revolution in the history of pliilosophy. § OM. We now consider one of Hume's skei)ticul | //«'"';'" conclusions, lie holds that we have no idea of tuhftnur,. suhfitance except as a collection of qualities or im- pressions ; no idea of it as the unknown cause of our known sensations. He holds, also, that it is impos- sible to infer conclusively that our simple sensations are caused by the Divine j\Iind. But, at the vame time, there is an admission that sensations must have an origin somehow and somewhere. Sensations, lu; says, "arise on the soul originally from unknown causes." " An im})ression first strikes upon the senses and makes us perceive heat or cold, iVc." There is here, consciously or unconsciously, an admission that there is something beyond, or behind our sensations, which we cannot indeed hiow, but the existence of which we cannot deny. Connected with the origin of our sense-knowledge — that is, connected with the real existence of things — there is, Hume admits, a problem to be solved, which, however, he thinks in- soluble. " An impression strikes upon our senses." Take almost any one of these words, and you cannot understand its meaning without taking for granted that very unhiown which Hume wished to banish. I ;■■ !« 1] jf v. w I !■; I m V'i '15- III 1 lO < iiAP. iir. SKCT. V. Kxiili:^(()U. THE ELEMENTS OF THE Impression implies some receptive thing upon wliicli some otlier thing presses, so as to leave its mark. What is that other taing whicli makes the impres- sion upon the senses? Ilume cannot answer; but he cannot employ ordinary language, he cannot invent a language, which does not imply that beyond the sphere of our immediately known sensations there is another sphere which we are bound to believe in, but may not completely know. Hume started with the assumption that we have no ideas but what are copies of sensations, and the skeptical conclusions to which he was led are the reductio ad ahsurdimi of his principle. His principle landed hhn in a conflict witli beliefs of which he could not rid himself, and he certainly showed groat fortitude in throwing over- board those beliefs for the sake of logical consistency. But it is questionable if he was really sincere in doing so, and tliere is some reason for supposing that his design was simply to show the absurd conclusions to which his predecessor's principles naturally led. This at least he did, and did it with remarkable effect. § G4. Hume's view of the origin of the idea of extension must now be referred to. As he was not at liberty to admit any idea which was not a copy of a sensation, and as he could not deny that we have an idea of extension, he was bor.^d to show that it was a copy of some sensation. He accordingly assumed that sensations or impressions, as he called them, were extended ; then abstracted his mind from the quality of the sensation, as colour, &c. ; then, as the PSYCHOLOGY OF COGXITTOX III SliCT. V, result of the abstraction, appears the idea of pure chap, m extension. And as the idea is a copy of the sensation, omitting the particular colour or tactual quality, it follows, of course, that the idea is extended. But as. it is an ahstract idea, it can have no existence apart from the concrete sensation from wliicli it was abstracted. One wouhl have supposed tliat the in- congruity of making an idea a coj)!/ of an extended thing would have been sufficient to makii Hume abandon his principle altogether. But no ; ^\ itli a pertinacity worthy of a better cause he determines that, come what will, he will adhere to his principle. His doctrines, that the idea of extension is a copy from a sensation, that space and time are abstrac- tions from concrete experiences, will be criticised hereafter.* § Q)b. As the skepticism of Hume formed such an important crisis in the history of modern philosophy, and as it is the natural conclusion of all that went before, it may be as well to present, in a brief form, a view of the important problems wdiich had hitherto occupied the attention of psychologists, and the ways in which their solution was attempted. TIk.' diagram on the next page is an attempt to illustrate, in a ; rough way, the problems which psychologists have I set themselves to solve. Let the circle 11. C. H. T. S. | with I. in the centre, represent the mind and its \ sensations ; R. indicating resistance, C. colour, H. j liardness, T. taste, S. smell. I. indicates the ego or I subject of consciousness. *■ Sec § 8;j. \ Gem nd Hiir of ''ill proh- U I an. i\ li ■J I 1 1 !: i!:' V i' ■', ■ S ii ^1 112 (UAV. III. SECT. V. TllfJ ELEMENTS OF THE The capital letters E. C, &c., indieato actual sensations, and, since tlioy are i'elt in tlie body, E. E., tlie circnrascribed circle may represent the extension of the organism. The small circle to the left hand, r. c. h. t. s., indicates the mind in a state of reflection, and each of these letters stands for the representative or tlie idea of the sensation indicated by the corresponding^ capital. The circle to the right hand, havini^ in the centre, indi- cates the object, supposed to liave independent t existence, and consisting of the qualities II C, <^c., I all comprehended in E^ E, objective extension. I The small circle at the extreme riuht may repre- sent the unknown matter, consisting of unknown powers, i\ c^ etc., corresponding to the known qualities, Jx^ C (Sec, which constitute the object of perception. Ml I, nils of ■•iluibjuni § GO. Now, in examining the problems connected i with the process of knowing and the objects of know- ledge, there have been adopted, as we have pointed out, two methods. According to the first of these, the continuous and independent existence of the object O. is assumed, and the problem is to explain the relation between O. and I., between the extended object and the perceiving mind. And as it is also 1 5, PSYCHOLOGY OF COOyiTIOX. 113 t'HAr. III. SKCT. V. assumed that I. and 0. are so utterly differout iu nature that the former cannot know the latter, it i becomes necessary to interpose between them some ^ intermediate and representative idea. Hence, the Erpn'-M-ii- sensations R. C.H., &c., or the revived sensations r. c. | Unun/ h., &c.y or some combinations of them, are thoui^ht 1 to be representatives of the object 0. and its qualities. I But after a more careful analvsis, it comes to be seen that zome of the qualities, such as C, H T 8 a"e really identical with sensations C. H. T. S., and when this discovery is made, there must be a correction of the representative theory. C, colour, is purely subjec- ! tive, and so are H. T. S. ; therefore, there are no i qualities C^ H^ T^ S, to be represented, nothing but i certain unknown powers, c h^ t s,; consequently, the Mmiijir,!, sensations C. &"c., which are immediately known, are | made to represent these unknown powers. But here another difficulty presents itself. How can you say that something which is in itself utterly unknown is 1 represented by something that you know ? And, I especially, how can you maintain that idciis of your mind are ideas of an unknown and unknowing- 1 matter? These are tl;e questions thtit Berkeley Orer- asks, and by them overturns the representative theory. ' '™"""" The sensations R. C, &g., are not representatives at > all ; thev are the real thiuos which exist. Tlicv arc identical with R C, &c., the distance and externality \ being only apparent, not real. 8ke})ticism regarding j matter and space, begun in Berkeley, is continued j and extended in Hume. All knowlediie comes i through sensation. But matter is not a sensation, i 1 ^i= :\ ; ■ n wk!» '■■ i «l ilii ' j 114 oiiAi'. in. SKCT. V. Difl'i'mil I if rcprr- ■:anic illusion ; ! and in the fourth, it indicates an inference which we ' make regarding the cause of our sensations. The impropriety of regarding ideas as representatives in any of these senses except the first was clearly I l)erceived by both Berkeley and Hume ; and the { errors of these philosophers, if such there are, must be looked for, therefore, in their views of the nature or origin of ideas. The former thought that all ideas — that is, objects of knowledire — must, as beino: ideas, exist in some mind; the latter maiiitiiined that all ideas are copies of some sense-impression. Hence the id(^alism of the former and ske[)ticism of the latter. , § 68. Tlie conclusions of Berkeley and Hume may Grounrj (,/ be regarded as the redudio ad ahsnrdum of rcprfisen- tative idealism as found in Descartes and Locke. I 2 nacfii '.r ■1 ■ ill un THE ELEMENTS OF THE cuAv. ni. SECT. VI. i i shocked. But in these conclusions there was something un- satisfying to the human mind. People can scarcely bring themselves to think that the objects which they perceive have, or involve, no reality except the fact of their being perceived. Nor is it easy to think that space, or. the externality of objects with reference to our minds, means simply the possi- bility of being perceived by another mind. It was, therefore, to be expected that there would be a reaction acrainst the conclusions of Berkeley and Hume ; and that tiiat reaction would seek to establish, first, the permanent and independent existence of a non-ego other than a mental one, and second, the existence of ideas which are not merely copies of sensations. By the efforts of Reid and Kant this was attempted. Section VI. KEiD (1710-1706). § 69. Reid, like many other people of his time, was greatly shocked at the ske[)tical conclusions drawn by Berkeley and Hume, and he set himself with great ardour to refute the system from which he believed them to follow. The conclusious that there is no matter and no mind, that all the objects in the universe are nothing but floating impressions and ideas, were so utterly repugnant to his practical good sense, and so utterly repugnant to the ordi- nary beliefs of mankind in general, that he resolved to see whether some foundation foT philosophy could PSYCHOLOGY OF COGXITWX. IID- h not be laid, upon which it would bo possible to build more securely the structure of human knowledge and belief. To this task lleid brought a great deal of candour and honesty, a fair amount of learning, and a great deal of good sense. But, unfortunately, he did not understand either Berkeley or Hume, and he was not at all clear as to what position he ought to take up in order suc- cessfully to refute them. He resolved to appeal iroui the philosophers to the common sense of man- kind, which is a more or less satisiiictory appeal according to what is meant to be included in the term common sense. Generally speaking, he appears to mean by it that practical good sense which leads men to trust to the testimony of their senses, and to believe in the existence of the world and a variety of other things. Sometimes, however, he gives it a more scientific meaning, and describes the principles of common sense as those beliefs which result from the constitution of our nature, and which are neces- sary and universal. Then taking his stand upon these principles, he thought that he was able to defy the most insidious attacks of the skeptic. Like the good knight, Fitz-James, he addressed his foes, the idealistic philosophers : — " Come one, come all, tin's rock bliall fly From its firm base as soon as I." But, unfortunately, it was not long before he went over to the camp of the enemy, cut his connection with his first friends, the men of common sense, and ir CHAP. in. SECT. VI. Jleiil milUant. 1.: ; n ! i llS THE ELEMENTS OF THE CHAl'. SECT. III. VI. m Ikld ir}((is. began to philosophise just as recklessly as any that had gono before him. § 70. We must now proceed to consider what it was that he accomplisliml or attempted in the in- terest of psycliological science. And, at the outset, we observe with satisfaction that he noticed the improper use which his predecessors had made of the word idea, lie saw that there was no mental object numerically different from a mental activity ; that the act of conceiving and the mental concept were really identical, being the same thing looked at from different sides. Consequently, when he sf)eaks of ideas or any other mental objects, he considers them as equivalent to mental activities or states. He brought into prominence also the fact, which Berkeley had clearly pointed out before him, that the ideas or phenomena of the mind do not at all resemble the qualities which he believefl to exist outside of him and to constitute the material world. There can be no resemblance between the sensation of colour and the objective quality which causes it ; nor between the sensation of touch or pressure and the objective, hard, and extended body which occa- sions it. Thus thought lleid ; and in establishing this position he believe««W«l!«»j01t««i.,.-..-^ , I fill 126 THE ELEMENTS OF THE CHAP. Til. SECT. VII. Sensation. from any other proposition, unless from one equally involving the idea of necessity, it is absolutely a priori. An empirical judgment never exhibits strict and absolute, but only assumed and comparative, universality."* To show that there are such necessary and univer- sal judgments, Kant appeals to the sciences of Mathe- matics and Physics. We are not concerned with the general use which he makes of this distinction between the a priori and the empirical elements of knowledge ; we have only to study its application to the psychology of perception. And in this we shall see a very important difference between the German and the Scottish opponent of Hume. § 76. According to Kant, sensation is the result of objects affecting our sensibility oy sensive faculties in a particular way. Thus, by means of sensation we have an intuition of pha^nomenal objects. That in the phaenomenon which corresponds to the sensation, Kant calls its matter ; but that which effects that the content of the pha^nomenon can be arranged Matter and '. uuder certain relations, he calls its fo7in. But that in whicli our sensations are merely arranged, and by which they are susceptible of assuming a certain form, cannot be itself sensation. It is, then, the matter of all phajnomena that is given to us a posteriori, the Ibrm must be ready a priori for them in the mind. By an easy analysis, Kant reaches the conclusion, that the two forms of intuition, without which the cognition of phoenomena would be impossible, are * Kant's Introductiou. s c rSYCnOLOGY OF COGNITION. space and time. It is Avitli the former that we are now concerned. The following are the principal elements of Kant's exposition of space : — (1.) " Space is not a conception which has been derived from outward experiences. For in order that certain sensations may relate to something without me, and in order tliat I may represent them, not merely as without of, and near to, each otlier, but also in separate places, the representation of space must already exist as a foundation. (2.) "Space, then, is a necessary representation a 'priori, which serves for the foundation of all external intuitions. (3.) " Space is no discursive, or as we say, general conception of the relations of things, but a pure in- tuition. (4.) *' Space does not represent any property of objects as things-in-themselveSj nor does it represent them in their relations to each otlier. (5.) " Space is nothing else than the form of all phaenomena of the external sense — that is, the sub- jective condition of the sensibility under which alone external intuition is possible." The substance of Kant's doctrine of perception is summed up by himself as follows : — "All our intuition is nothing but the representa- , tion of phaenomena ; the things which we intuite are ! not in themselves the same as our rcpiesentations of ! them in intuition, nor are their relations in them- 1 selves so constituted as they appear to us ; nnd if we take away the subject, or even only the subjective . 127 t'HAr. HI. MECT. VIl. Sjjace. Sumnuiri/ •if Kdut'n ilodriiu: If 'i- \r; ^> u mmf I 128 THE ELEMENTS OF THE l,V 11 r CHAP. III. SECT. VII. Criticism. constitution of our senses in general, tlien not only the nature and relations of objects in space and time, but even space and time themselves disappear ; and these, as phsenomena, cannot exist in themselves, but only in us. What may be the nature of objects considered as things-in-themselves, and without re- ference to the receptivity of our sensibility is quite unknown to us. We know nothing more than our mode of perceiving them ; and with this alone we have to do. Space and time are the pure forms thereof; sensation the matter. The former alone can we cognise a priori — that is, antecedent to all actual perception ; and for this reason such cognition is called pure intuition. The latter is that in our cognition which is called cognition d posteriori — that is, empirical intuition. The former appertain abso- lutely and necessarily to our sensibility, of whatsoever kind our sensations may be ; the latter may be of very diversified character. Supposing that we should carry our empirical intuition even to the very highest degree of clearness, we should not thereby advance one step n-^arer to a knowledge of the constitution of objects as things-in-themselves."* § 77. One great merit which we must ascribe to Kant is the dismissal from his psychology of all accidental side questions, and the clear presentation of the fundamental problems which the psychologist endeavours to solve. The process of perception is reduced ultimatelv to a consciousness of sensations, * These qnotations from Kant's ' Kritik,' are from Mr. M( iklc- john's tniuslalion published in liohn's series. rSTCIWLOGY OF COGNITION. 129 varied in character, but all ap^reeing in having, as a condition of their possibility, particular forms. Through these sensations there is made known the existence, although not the nature, of things-in-them- selves. The essential problems of every system of psychology must have reference to (1) sensations, or whnt Kant calls the matter of sensations, (2) space and time, called the form of sensations, and (o) the thing-in-itself, or whatever it may be called, supposed to exist independently and as the cause of sensations. There is a fourth problem not so funda- mental, regarding the process by which sensations form themselves or become transformed into distant objects of perception. Here we have presented in very small compass the subjects of all the disputed cpiestions of psychology, and if psychologists only understood one another, the probability is that there would not appear so great a difference between their views as is now supposed. With regard to the first of these problems, the nature of the immediate objects of consciousness, Kant makes no distinction between the sensations and the mental acts which they constitute. But still tliey are mental, purely mental, and called by hiin representations of other and unknown objects of intuition. We shall have to notice, in a subsequent { philosopher, an important difference regarding this question. The cardinal doctrine of Kant's psycho- logy of perception is, however, the a irtiori and pha3nome'nal character of space and time. Space and time are subjective in their oiigin, and are CHAT. III. SKCI'. Vll. Iiiimedkiti objtetn of cdiisci'on.^- tiiiit. ,' i t i'\ r I ■ ! uo THE ELEMENTS OF THE VMKW m. 8ECT. VII. TltlnriH-in- llii'rimdres. conditions only of pbaenomena, not of things-in- themselves. This problem also, we shall find,* gives rise to a great deal of discussion. An investigation into the nature of the so-called things-in-themselves is not properly a psychological one, although psychology has to do with the grounds of our belief m them. Kant considered them beyond the sphere of human knowledge, but Kant's German successors broke through the trammels which he had attempted ^npose upon the human intellect, and speculated I ' \>oh\i. regarding the nature and laws of what he pronounced unknown. Into these speculations it v/' ':ld b' 'inconsistent with our subject to enter. Bat the ps. oL, logical doctrines of Kant have been fruitful in stimulating and, to a certain extent, in guiding subsequent researches into the |>erennial problems of thought which he apprehended so clearly. Any criticism of Kant's doctiines, we shall not now atteini)t, but leave it to be done by those of the present generation to whom we must now devote some attention. Our historical review will, we trust, have produced two good effects ; it will have enabled us to see the most important errors of the earlier psychologists ; and will have given us a clear appre- iiension of what are the fundamenttd problems of the psychology of perception. * lis 82-81. I t i rSYCIIOLOGY OF COGNITION. \\l CHAV. III. SECT. VIII Section VIII. MODERN ENGLISH PSYCHOLOGY. b'fwhj It/ inodtrii § 78. Was Kaut successful in Ids refutation of Hume? By the principle which Kant endeavoured | ^'>"Jc/jo/'n;/*/. to establish, was philosophical skepticism rendered impossible or absurd ? For an answer to these and similar questions we must look to the history of modern psychology. Hume and Kant are the representatives of the two great schools of modern English psychology, and it shall be our task in this closing section to refer, as briefly as possible, to the fundamental questions regarding which these schools are at issue. It would be impossible, within the space to which we propose to confine ourselves, to give anything like a fair account of even the most important of the psychological works of the present time ; it would be equally impossible to do justice to the philosophical ability and learning with which } the great problems of psychology have been treated. All that we propose to do is to introduce the student to a sphere of research of great interest and great extent, and to furnish, perhaps, some stimulus and some guidance in the pursuit of knowledge. We shall not, therefore, as iieretofore, consider each j psychological system by itself, but shall give an account of the manner in which psychological problems and difficulties have been treated by difterent writers. For the sake of brevity, we shall endeavour j K 2 Nl 4 h . V .'< '■ m 1 I 1, r ,i M 132 THE ELEMENTS OE THE niAT III, HKCT. vm I'rohhms. O'ljects of lanscioiif- to avoid evorytliiiig of secondary iinportaiioe and of merely liistorioal interest. We sliall restrict our- selves to tlio consideration of tlie few essentially important problems which must bo solved in one way or another by every psychological system ; problems which have already been pointed out in connection with Kaut. The attempt to ascertain, or accurately to state, what a philosoplier really means is frequently eittended with considerable difficulty ; and we have prominent examples of the evils arising from a disingenuous or a prejudiced reading of the doctrines of another. This we shall endeavour to avoid, and give as briefly and accurately as possible the doctrines which we propose to discuss. § 79. Kant's general doctrine, that there are certain a p'iori truths or principles which could not originate in experience, may be better discussed at a future time. At present we are concerned chiefly with the modern doctrines concerning : — (1) Sensations, or the immediate objects of con- sciousness ; (2) space and time, especially the former ; (3) the object and the process of percep- tion ; and (4) the believed objective cause which may account for the existence and permanence of the objects we perceive. The question as to the nature of the immediate objects of consciousness is one of great importance. It has been almost universally held that the objects of which we are immediately conscious are ideas purely mental, either identical with the act of consciousness, or numerically, but not in nature, different from it. PS YCJIOL r; Y O F COC XITl X. it. /J i 'Die uamo!< whi(!li have been given to tlioso objects ;ire various; sensations, impressions, idea-!, rcpre- sentiitions, and so on. Whatever tlio name may be by wliich they are designated, tliere lias been a re- markable concurrence in consid(3ring tiie immediate objects of consciousness simply niodifir-iitions, or activities, of the ego. Such is still the doctrine of i those who adhere to the Berkeleian idealism ; such is the doctrine of nearly all the xVssociation school of psychologists represented by Hartley and the two Mills. In opposition to this view we have tlie doctrine to the establishment of wliich Sir W. Hamilton devoted his learning and abilities — the doctrine that the immediate object of consciousness is not merely a mental product, but that it is the non- ego. There is frequently a great deal of difficulty in reconciling Hamilton with himself, and in getting a really intelligible view of his psychology. He frequently speaks as if distant and material things were objects of consciousness ; and as if the impres- sions made upon our organs of sense were objects of perception. But laying aside both of these erroneous and un- guarded statements, and interpreting him in a fair and candid spirit, it appears to us that the essential point of his doctrine, as distinguished from that which we have before referred to, is as follows : In conscious knowledge there is an ego and a non-ego, a subject and an object, known in contrast to one iinother. The object is an affection of the sensorium, a sensation of some kind, say of colour, resistance, or CHAl'. 111. SECT. VI 11. ^1 J nu). T 134 THE ELEMENTS OF THE Assodn- tioHdl awl intuitUmal "chouh. ( iiAi'. III. I sound. But although a sensation, it is or reveals a veritable non-ego in immediate contrast with the ego. Conseious knowledge is, in fact, impossible which does not set over an object against the subject ; and in relation to perception that which is thus objectified is a sensation. Thus sensations, although immediately known in consciousness, are not there- fore purely mental ; they contain a foreign element ; they belong to, or constitute, the non-ego of our immediate knowledge. § SO. This difference of view regarding the nature of tlie immediate objects of consciousness is a funda- mental distinction between what we may call the Associational and the Intuitional schools of psy- chology. It must be accepted as a fixed principle of association that nothing can appear in the result of the process of association which was not involved in the original elements.* Now, according to most of the members of the associational school the origi- nal elements to be associated are sensations in cer- tain relations. If these sensations are nothing but activities of the ego, if they are purely mental products, it is manifest that the objects into which these sensations are clustered and bound together by association can never become anything else but mental. If they are at the beginning, they must continue to be, unto the end of the associational pro- cess, simply mental states or activities. And in the writings of the consistent association psychologists, * That is, nothing diflferent in hind. We have seen that asso- ciations of sensations may give rise to new sensations, see § 16. 1 >. PSYCHOLOGY OF COGNITION. JD i us Hume and J. S. 3Iill, we find tlitit tliis is acrtuuUy the case. Objects are clusterd of sensations suj)|)(>sed to liiive a permaueiit existence independent of tlio ! individual mind, iu conseqiK'nee of their mutual eo- lierenee and regular recurrence. Tliey are mental j products objectitied, and called by Mr. IMill Pernui- nent Possibilities of Sensation. He has been cen- sured for using such a negative term to indicate what other people tliink to be a collection of positive and non-mental powers. But tlie term is the very best he could have used. Befj^inninf? his associative process with purely mental elements, ho could never reach to that which is non-mental. And if his psy- chology may be condemned because it does not recognise that which is essential iu our knowledge of a material world, it cannot, at least, be condemned for its inconsistency. § 81. The other view, which we consider the cor- rect one, regards sensations as being, or involving, subject 'plus object ; there are in consciousness given an ego and a non-ego; there is something in the object of consciousness other than a merely mental state or activity. The full significance of this we shall not attempt to bring out at present. But in the meantime, we can see that there is not the same difficulty in attaining to a knowledge of a veritable objective world as in the former ease. We can see that the association of elements already containing a true non-ego could easily and consistently lead to the ultimate result of the perceptive process, the know- ledge of objects constituting a real world. We may CitAI'. III. sEi r. viii. Til fa i- iiomd t^fitiiil- lioiiil. fl I 136 Till-: ELK M EST ^ OE THE n\Kv. III. «E( T. VlJl. 'i I'ljti'iifiiou, h priori IliinriJ, now advance to tlio consideration of anotlicr funda- mental dirtV'rence between tlio two psycliolo^^acal arliools. Tills dilTeieneo lias ref(nvn('(^ to tlie naturu of our cognition of space or extension. § 82. Kant, in order to withstand the skepticisn '^^ Hume, gave to space and time an a 2>riori origin ..^ tlie native /orwi of our sense-intuition. The con- ee^)tions of space and time are not derived from experience, bnt they are the conditions by which experience is rendered possible. It is impossible to perceive any object or quality except in space, and this necessity at the very beginning of experience, it is alleged, could not be the result of ex[)erience. The necessity, however, is a subjective one; space and time have only a phenomenal reality; things-i themselves do not exist under spatial and tempc conditions. Now, if by a lyriori, Kant meant only to oppose Hume's maxim that all our liiiowledgo consists of impressions or sensations, and ideas, which are the copies of sensations, he appears to have suc- ceeded. That which is at first a neeessarv condition of intuition cannot itself be tlie product of sense — ex- perience. But the expression a p'iori appi ars to in- volve a view which modern i)sychologists are anxious to avoid. It appears to convey the idea tiiat there is in the mind some hidden receptacle of unconscious forms or principles which are ready to start up into conscious life whenever the first incipient experience calls for them. This hidden limbo of a priori |)rinei- ples which cannot be examined by the light of con- sciousness is most convenient for those psychologists rsivi/oJAJuy of cucimtklw U7 riiAl'. III. siocr. VIM. of itufiiriii- who think tliat it is ji .siinicient c'Xi)luiiati()n of till tlicir beliefs, whether siinph* or eonijilox, which tliev euii- iiot get rifl ol'. But it nii]>ears at lirst si^^ht iin- jdiilosephical to iittenipt to exjdiiin u dinieiilly l>y ii mystery; to aecount lor souh! necessity by ((sxiinihif/ the niiteeodeiit existence of some form or |»riiiei|)lo ill some hidden mental labyrinth beyond the ken of consciousness. § 83. Leavinj^ for the present Jvant's a priori ex- planation of space, we may examine the doctrines of more modern psycholof::ists n^mirdinf; it. These ! ''"" '"' "''- 1 • 111 11.1 etroction. doctrines may be reduced to two. Jn the iirst jwaco, it is maintained that the idea of sj)ace is the product of some process of abstraction iv association ex- ercised npon sensations ; in the second plac(s it is held that space is given in intuition. With reference to the first of these doctrines, we have already examined* one form of it as held by J. S. MIW, and seen the impossibility of the attempt to evoho space fi'om time. And if we consider for a moment the nature of the processes of association and abstraction, we shall sec that neither of them can account for the origin of our knowledge of space. Association unites together sensations, or other objects of in- tuition, into a compound ; but the compound thus formed cannot possibly contain anytliing which was not in the original elements associated. Suppose that our only original intuitions are nncxtende 1 sensa- tions and the relation between them of succession or time, it will be impossible for any association * § 28. Hi .1 '' u I ^ i;. 138 THE ELEMENTS OF THE CIIAl'. III. isECT. VIII. i ,|i U ( Extension, an intui- tion. to convert either sensations or time, or any com- bination of the two, into space. The most elabo- rate attempt to do so is that of IMr. Mill, and it, we have seen, is a failure. Equally impossible is it for the process of abstraction to produce anything not involved in the original objects of intuition, or in the perceived relation between them. Suppose that we are conscious of redness, greenness, blueness, and other particular sensations of colour. We are able to cojnpare them, perceive their resemblances and differences, and form a general idea indicated by a general name, colour. Now, in the result of this process there is nothing contained which was not given in the original intuitions ; the result is just the summing up, as it were, of the original intuitions of particular sensations and their relations. In this case abstraction is employed for the purpose of generalisation, for the formation of a general idea or name. But space is not a general name ; it is not predicable of an}'^ of the objects from which it is said to be produced by abstraction.* Nor is it in any way possible to know by abstraction from objects of consciousness what was not known by intuition in them. Those who maintain the contrary have yet to show its possibility. § 84. The other modern view regarding the origin of our knowledge of space we have already expounded in chapter second, and to that exposition now refer the reader. Extension, a form of space, is, we believe, given in intuition ; if not, we do not see how * See Spencer, * Paychology, ' ii. 352. rSYCIIOLOGY OF COGNITION. 139 it can be known at all, as it certainly has hitherto proved incapable of resolution into anything else. At the same time, although the essential element of extension is given in intuition, it must be admitted that abstraction has something to do with the elabo- ration of our notion of space. Abstraction must be made from the particular sensations or qualities which are given in intuition as extended, and there remains the extension without the quality, the form without the nuitter. But this abstraction manifestly does not fvoduce our idea of extension, it simply disentangles it from the sensation or quality in which it is involved. With reference to the nature of space and time, there are many questions which have long exercised the minds of thinking men. Are they real things, having independent existence ; or are they only attri- butes ? Can we conceive empty space or time ; or are they always connected with sensible qualities or objects? What is the naturn of our conception of the whole of space and time ; is it that of the infinite, or only of the indefinite? A reference to the modern doctrines regarding these and other questions would compel us to exceed our limits, and ve must therefore refer the student who wishes to pursue his inquiries farther to the many able works upon these subjects which have been produced in recent times.* § 85. We must now give some attention to modern doctrines regarding the object and the process of perception. And we remark at the outset that it * E. G. Hoilgson on Space and Time. CHAP. III. SECT. VIII Perception. I II |: ' i I40 THE J-JLEMPJyTS OF THE CHAV. in. SKCT. VIII, ih: seems desirable for psychologists, when adopting words that are in conjinon use, to give them as nearly as possible the meaning sanctioned by ordi- nary usage. The word perception, when used by ordinary intelligent men, has a certain definite meaning and object ; it means the knowledge which we have of objects at a distance from us, believed to have an independent and permanent existence, whether they are perceived or not by us or any other sentient being. But psychologists have con- cluded, and rightly, that this knowledge is a very complex product , they have analysed it into what they have believed to be its simplest elements ; but \ instead of keeping tlie name perception to its proper object, the complex product, they have ap^died it to ; some of the more sim|>le processes into which the I complex has been analysed. And as it has not been applied uniformly, considerable confusion has been caused. We have next to refer to a false distinction be- tween two opposing psychological schools. j,One school has been called the associational school,p>' another the intuitive. The distinction is not an accurate one. All psychologists agree that the object of perception, as we understand and have just explained that object, is not intuitively known. All psychologists must assume at the beginning of the construction of tlieir acquired knowledge certain objects which are intuitively known. All psyclio- logists make some use of the principle of association in explaining the construction of their knowledge. PS YCnO 1. G Y OF CO GNl TJOX. 141 1^ )een wo I The onlv important differonfcs which exist be- ; cuAr. m. *' I SECT. VIII. tween psychologists have referenee (1) to the number and kind of the objects of intuitive knowledge, (2) to the extent of the use which may bo made of the principle of association, and (3) to the question whether association can exi)lain everything, or whether some other principle must be called in. § 80. 3[r. Mill, w ho is the representative of a Mr. Mi!!'.< large class of psycholcjgists. past as well as present, '//,J,V'o'/"<( assumes, as the original contents of intuitive know- '""'"■'"' ledge, certain sensations or states of consciousness, and the relations of co-existence and sequence exist- ing between tli(^m. Upon these original intuitions he sets to work with his laws of association, and attempts to explain our belief of tlie external world. We have already seen with what success he has attempted to account for the origin of our idea of extension or space. We must now examine his attempt to explain our knowledge or belief of a permanent material world. Beginning with the existence of sensations, he maintains* " that there are associations naturally, and even necessarily, generated by the order of our sen- sations and of our reminiscences of sensation, whi(di, supposing no intuition of an external world to have existed in consciousness, would inevitably generate the belief, and would cause it to be regarded as an intuition." In support of this he shows that, in certain circumstances, sensations which we have felt recur to us regularly upon the fulfilment of certain * ' Examiiifition,' p. 221. . Ik '^ i i u 'il Ik 1 I IS 5 142 r///;; ELEMENTS OF THE CHAP. III. BECT. VIII. conditions ; that thus we think of tlie^j^^^'^^^^^l^^y of 1 the recurrence of these sensations as_ being: per- j manent, whereas sensations themselves are fiigitive ; that it is not merely single sensations, but groups of sensations, which are thus connected with permanent possibilities of them ; and that the sensations of these groups occur in a certain fixed order. " Hence," he concludes, " we speedily learn to think of Nature as made up solely of these groups of possibilities, and the active force in Nature as manifested in the modification of some of these bv others. The sensa- I tions, though the original foundation of the whole, I come to be looked upon as a sort of accident depend- I ing on us, and the possibilities as much more real j than the actual sensations, nay, as the very realities ; of which these are only the representations, appear- i ances, or effects. When this state of mind has been arrived at, then, and from that time forward, we are never conscious of a present sensation without in- stantaneously referring it to some one of the groups of possibilities into which a sensation of that parti- I cular description enters ; and if we do not yet know • to what group to refer it, we at least feel an irre- sistible conviction that it must belong to some group or other, i.e., that its presence proves the existence, ! here and now, of a great number and variety of pos- i sibilities of sensation, without Avhich it would not ; have been. The whole set of sensations as possible, i form a permanent back-ground to any one or more f of them that are, at a given moment, actual ; and the possibilities are conceived as standing to the PSYCHOLOGY OF COGKITIOX. 143 tlie actual sensations in the relation of a cause to its chap. hi. effects, or of canvas to the figures painted on it, or of a root to the trunk, leaves, and flowers, or of a sub- stratum to that which is spread over it, or, in trans- cendental language, of j\[atter to Form.''* J lore, then, \ we have the external world produced by IMr. JMill / from sensations variously associated togetlier. -^ § 87. Now, let us pass over the question, how Critichm. ]\Ir. Mill gets his sensations projected into space, which he does not explain, and refer to another point of more vital importance. He speaks of " the active force in nature, " but we may ask how he comes to know anything about such a force ? Force is not a sensation, nor is it any association of sensa- tions. This, however, is not the main point of our criticism. " The whole set of sensations," he says, " as possible, form a permanent back-ground to any one or more of tliem that are, at a given moment, actual ; and the possibilities are conceived as standing to the actual sensations in the relation of a cause to its effects." Let us examine this statement. The possibilities of sensations are conceived as the cause of actual sensations. We have, for example, the sensation of a particular figured colour which is associated with the name orange. Connected Vvith this sensation there are a number of possible sensa- tions of smell, taste, touch, sound, - different sensation or sensations. But vet this is the onlv kind of cause which could be reached from the original elements with which he sets out by the help of association. He begins with sensations ; he ends with groups of actual and possible sensations having a fictitious objectivity. § 88. If, then, Mr. I\Iiirs laws of association ope- rating upon the original sensations of consciousness do not produce what we believe to be a veritable external world, we have now to inquire whether there is in his method any fundamental defect. The result of this inquiry will simply be an answer to PSYCHOLOGY OF COGNITION. 145 at I V the question formerly referred to, vhether some other principle than the laws of association be not | necessary to explain our belief in an external world ? \ We believe that there is ; and that the essential I defect of the psychology of which JMr. Mill is an \ exponent consists in the ignoring of this other })rinciple. In that psychology it is assumed that sensations exist ; l)ut no attempt is made to accou for their existence. Sensations exist in certain i relations of co-existence and sequence ; in some \ cases an invariable relation of antecedence and [ consequence is observed ; and by association the | antecedent comes to be lool^ed upon as the cause j of the consequent. And, from this association or phenomenal theory of sensation, we are led to the absurd conclusion that the possibility of a sensation of resistance, or smell, is the cause of an actual sen- sation of colour. Now, it is perhaps in the simple original sensations of our consciousness that we are able to see most clearly the fallacy of the phenomenal view of sensation which Mr. ]\Iill accepts. When we have a sensation, say of smell, or colour, or taste, although they are most intimately and inseparably associated together, we never look upon the one as the cause of the other. And yet we do give an account to ourselves of the cause ot these sensations. They are something beyond our own control; tliey come to us unbidden; and our very poiverlessness with reference to them compels us to refer them to some objective power. That power is, as far as our consciousness is concerned, unknown ; L tHAl'. Ill, SECT. VIII. \ 1 i I iP m ' 1 i- !■ t I I I I 1 : {■ I ■'M\ li 146 THE ELEMENTS OF THE cHAr. III. (JECT. VI H. hifrrred JlllCIIO- iiKua. it is not a phenomenon, although it is raanifosted to us in a phenomenon. Thus our conception of a sensation as being a non-ego involves a belief of some veritable objective cause of it ; and this intui- tion of the causal relation, whether strictly original or not, must be carried with us through the whole subsequent process by which our percejjtive know- ledge is built up. By the introduction of the causal judgment at this early stage Ave are able to account for the objectifying of our sensations ; and we are able to account for a belief in material body in which will not be involved the absurdity of one sensation, or the possibility of one sensation, being the cause of another of a different kind. According to this view, pilienomenal body consists of objectified sensa- tions collected together in a group by association ; but to this body the educated intellect does not attribute any causal efficiency. On the other hand, noil-phenomenal body, or matter, as it is called, is simply a synthesis of inferred powers, each power being inferred to account for the sensation or quality corresponding to it which enters as a constituent member into the group of qualities which we perceive. § 89. The statement of this latter view regarding the nature of the perceptive process in which the principle of causation is made use of, in addition to the laws of association, brings us to the last important point which we proposed to consider. The nature of the inferred causes of our sensations and their synthesis is a problem which the phenomenalism of PSYCHOLOGY OF COdXITIuX. m; 3sted to 11 of u eliof of s intui- original e whole I know- ! causal account ire able a which nsation, e cause to this i sensa- ciation ; oes not r hand, lied, is power quality itituent 1 we ;*arding ch the itiou to portaut nature I their lism of Ml'. jMill and his school does not toucli. And yet it is with this problem that a great deal of modern science has to do. Light, heat, electricity, Ibrce, as studied by physicists, are non-phenomenal ^xjuers, and the object of science is to ascertain their laws and relations. With this subject we have nothing to do, except to point out that a true })sychology must leave a place for it. The only }>lace which Mr. j\rill leaves for physical science is in that nega- tive, utterly tantalizing shadow of a thing which he calls the permanent possibility of sensations. Idealism postulates an intelligent power as the cause of the existence and objective synthesis of sensations ; i and to this there is perhaps no serious objection except that the language which is used frequently leads ordinai-y people to suppose that something very absurd is meant. Realism, as found in Herbert Spencer, and as supported by recent investigations of science, demands a belief in real objective non-phe- nomenal forces, capable of correlation with and trans- mutation into one another. Into a discussion of this we cannot enter; sufficient that we have pointed out its relation to the legitimate subjects of psychology. We must now close our discussion of modern theories of perception, although aware of many im- portant omissions and imperfections in our sketch. The necessity for brevity must be in part our apology for these. The student who wishes to pur- sue the subject farther will find valuable assistance in the works of Hamilton, Ferrier, Grote, Bain, Mill, Spencer, Hodgson, Lewes and others. L 2 CIIAI'. III. SK( T. VIII. '.i l^ |i! ■ ! mm 1 1 ' •' t5 i ;; 148 (-IIAI'. IV. st(/r. I. Sniijrcf, hi- trodutid. THE ELEMENTS OF THE ClIAPTEK IV. It E r II ES EX TA TIO N. Section I. CONDITION OF EErUESENTATION. § 00. We have already seen that in the process of the acquisition of presentative knowledge there is found mixed up with it a great deal of what is only representative. Our perception of any external object is a complejf of presentative and representative elements, of actual and ideal sensations. Thus, in the acquisition of knowledge, there is involved the possibility of presenting the elements of the know- ledge already acquired. This power of representation is of great importance, apart altogether from its being subsidiary to the perceptive process, so that we must devote special attention to it. By far the greatest part of our knowledge can be brought before con- sciousness only in a represented state ; and all the higher operations of the mind depend upon represen- tation as a condition of their possibility. Before entering upon a consideration of the laws and kinds of representative knowledge, we must first give heed to the question, how is representation possible? What are the conditions upon which the representing :i r PSYCIIOLOOY OF COGXITIOX. M9 ^^^ I in consciousness of forgotten knowledge (lepouds ? Sensations, once felt, disappear from consciousness ; knowledge, once obtained, whether very simple or very complex, drops into oblivion. After a long time the sensation may be more or less vividly revived, the knowledge more or less completely restored. In the interval it has been completely out of the sphere of consciousness. In its repr(}sonted state, its original cause, the object of presentative knowledge, is not present. The question is, how is the knowledge revived without the assistance of its original object? How is the sensation repeated without the concurrence of its original external cause ? As the objective cause of the recurrence of actual sensations in regular groups and order has been called the permanent possibility of sensations, so we might here speak, and with better reason, of the permanent possibility of phantasms or ideas as being the condition of represented knowledge. But the truth is that, in both cases, the permanent possibility is the very fact to be explained, and the mere statement of the fact is not the explanation of it. The general fact, then, which we know regarding this subject, is the permanent possibility of becoming conscious of phantasms or revived sensations. § 91. The explanation of this fact is a problem of very considerable difficulty. There is no extra- organic object necessary to aid in the recall of for- gotten knowledge. Sensations and perceptions, when forgotten, are altogether beyond the ken of conscious- ness. There are therefore no direct means of (.'IIAI'. IV. sKcr. I. tiiiii lii/iio- thclicnl. 111 i* -i lio THE ELEMENTS OF TJIK riiAi'. IV. .si:iT. I. Till, lii/jio- lln Mrlillll //(. ti'lirij. observing tlio condition of tlio |)ossiljiIity of tlicir recall. Consequently, as far as psyclu)lo the distinction between aetivitifs wln'eh are mental and ])Owors whicli are not mental, and if wa explain tlie latter as ])o\vers wiiicOi originate and operate' beyond the sphere of eonscionsness, we must reject the doctrine of mental latency. This distinction and (explanation, wliich cliara(;terise philosophical dualism as opposed to idealism, appear to ns to eorreapond to the truth of thin^^s, and,th(U'efore, we must seek else- where for an ex[)lanationof the permanent possibility of pluuitasms and ideas. § 93. The mental hypothesis being rejected, the only other possible hypothesis must refer us to some non-mental ex})]anatiou of the difficulty; unless, indeed, we take refuge in some supernatural ex- planation of it — which, however, would in the present day scarcely be thouglit scientilic. And as all realists or dualists admit a physical cause for their actual sensations, they can consistently offer no objections to the explanation of revived sensations by a non- mental cause. But as ex liypothesl there is no extra- organic object, the non-mental cause, if such there be, must be an organic one. Tlie examination of this hypothesis is tberefore transferred from the hands of the psychologist to those of the physiologist, and the latter presents us Avith his theory of unconscious cerebration. In the hypothesis it is assumed that every sensa- tion which has come into consciousness has been preceded and caused by some molecular movement in the substance of the brain ; it is assumed that the repetition, or continuance, of a cerebral activity, CHAl'. IV, SIXT. 1. llijpolht'sis. :t' ■' « u il i; i * ( nl' f : f ii !■ It2 t MAP. IV. >t;cT. I. Difficulties THE ELEMENTS OF THE occasioned by continued attention to the conscious feeling of which it is the antecedent, will liave the effect of making a permanent change upon the nervous tissue, and thus of registefing, as it were, the original activity, so that it may be easily repeated. It is assumed, farther, that in the complex net-work of nervous centres which constitutes the cerebrum, there is such a connection that any activity propagates itself from one centre to another, and to many others, and that this cerebral activity may either excite conscious sensations or not, according to circumstances. Here, then, we have all the essential elements of the hypothesis. There are, in the nervous tissue of the cerebrum, permanent registrations of forgotten feel- ings ; permanent nerve cells or clusters of colls pro- duced or modified by some past activity ; and these explain the permanent possibility of forgotten sen- sations being revived. Into the details of the hypothesis wo cannot at present enter, but offer the following remarks regarding its difficulties and advantages.* § 94. There is no possibility of observing directly the correspondence between conscious sensations and nervous activity. Neither is there any possibility of observing any changes which may take place in the nervous tissue of the cerebrum ; and if there were, it could not be said that these changes are the result of sentient activity. The evidence upon which the hypo- thesis is built is of a verv indirect and ol)scure kind, * Those who wish to pursue the sTihjoet fnrthi r arc n^fcrred to the writings of Herbert Spencer, Dr. W. B. Carpeuter, uud Frof. I3uin. f'M PSYCIIOLOGY OF COGNTTIOX. DJ CHAT. IV. SECT. 1. , Bum. consisting: of facts observed by the vivisection of in- ferior animals, foots connected with diseased conditions of the human brain, and a variety of facts connected with peculiarities of memory and imagination. Thus the hypothesis is connected with many diflliciilties and obscure problems which cannot as yet be said to be finally solved. These difficulties, however, should i ■•^ CHAT. IV. ^v.rr. II. Illm- 'it' H'f. ( v^' i ! ill i IT Hi ■Hi ^ ; i'< 'I r^! 156 CHAP. IV. SKCT. II. THE ELEMENTS OF THE From the process of perception also many illus- trations of the influence of contiguity in S23ace in forming associated groups might be drawn. In truth, co-existence in time and contiguity in space are usually combined together ; those objects which we have known at the same time have usually been close together in space, and both might be combined under one relation, that of contiguity in general. In tho next law — that of dependence, as of an effect upon its cause, an end upon its means — we have also a kind of contiguity. If we take the phenomenal view of causation, considering the cause of one phenomenon to be an immediately preceding phe- nomenon, this law may be completely reduced to the preceding one»of contiguity in time and place. We say, for example, that fire is the cause of heat. If this means that the bright coloured flame wldch we see is the cause of the sensation of heat which we feel, there is in the relation nothing but contiguity. But if it means that there is some real objective force which is at once the cause of the flame which we see and of the heat which we feel, there is some- thing more in the connection between a coloured flame and a feeling of heat than mere contiguity in time and pii'ce. Thus the possibility of reducing the causal relation to one of contiguity depends upon the viow of the nature of the causal relation which we take. If it only is a relation between phe- nomena, it is nothing but a special form of the law of contiguity, in which an antecedent phenomenon called a cause is joined in our thoughts with a •« PSYCHOLOGY OF COGNITION. 0/ consequent phenomenon called an effect. If it is a ' chap. iv. relation helieved to exist between that which is a _. ^ phenomenon and that which is not a phenomenon, | althougli the former is always associated with the latter, the connection of the two in thought exists, not because of frequent experience, but because of beini^ i^iven in an original or very primitive inference. As this latter is tlie view which we have maintained,* j we cannot reduce the causal relation to that of contiguity. The relations of similarity and contrast have very powerful effect in recalling previous objects of in- tuition to the mind. A single sensation of any kind leads us to think of any similar sensation of the same sense which we have previously experienced. So a whole complex of sensations which we have formed into an object leads us to think of other similar objects. Illustrations of this are so numerous and llimiliar that we need not specify. So when simi- larity is made conspicuous by its absence — that is, I when objects are strikingly in contrast with one another — the one has a strong tendency to recall the other. The other relations of things produced by the same power or conversant about the same object, of .-•■igniiied and signifying, of things designated by the same sound, are so obviously reducible to one or other of the preceding that we need not give to them special attention. In addition to tiiose which have been mentioned, tliere are many other special * Sc(j §§ 3C, SS. . i'tl .1 i! ' . \ ■Si if. fl :t If ■ i! . I f I ' 1^ M 1:^ ■. r*' 15S THE ELEMENTS OF THE CHAl'. IV. SECT, II. lirdlicn] to iiiDi'f (jciie- ml 1.(1 U'K, n>'fjhif,' (lidtiiin. fiifcijra- tidll. relations Avliicli may form a ground of association ; but probably there are none which might not be reduced to one or other of the three important rela- tions to which we have referred — those of contiguity, causation, and similarity. § 97. Various attempts have been made by philo- sophers to reduce tliose special relations which form the basis of association into more general laws. Prof. Bain reduces them to two, the Laws of Con- tiguity and Similarity, Hamilton and others to the Laws of Simultaneity and Allinity. A still higher generalisation reduces all these to one — that of Redintegration, first announced by Augustine, and afterwards adopted by many subsequent philosophers. It is thus stated : Objects that have been previously united as parts of a single mental state, tend to recall or suggest one another. This, however, is so ob- viously open to the objection that it does not account for the formation of new associations never before perceived, that it has been modified into what has been called the Law of Integration, " which may be defined as that whereby the mind, in all its efforts, completes a circle of thought — in other words, brings a whole into all its reju'esentations. If we suppose, for example, the case of one face, from some point of likeness in it, snggesting another, let us see what is the mental process which takes place. The mind, on apprehending the particular point of resemblance in the face before it, immediately begins to complete the image thereby recalled. It feels that it has got a part of a whole formerly familiar to it, and its •( r PSYCHOLOGY OF COGNITION. ^59 ciatiuii ; not l)(? int rela- itiguity, y pliilo- ch form l1 laws, of Con- liers to A still -that of ae, and jophers. iviously recall so ob- leconnt beibre lat has nav be efforts, bring-s ippose, oint of vhat is ind, on nee in nplete 3 got a id its immediate aim is to bring into view that wliole. In ordinary instances the image completes itself in- stantaneously, and we are not therefore conscious of any such aim ; but in some instances, it is only after frequent efforts that it does so (as when we see a face resembling one that we cannot yet recall), and then we become distinctly conscious of the reproductive operation. The eye, or moutli, or whatever {)artof the strange face is recognised as famih"ar, is fixed upon by tlie mind, and becomes the centre of a re[)resentative picture which the mind has no satisfaction till it has completed. In the case of the law of contrast, as when night suggests day, good, evil, a dwarf, a giant, the mental process is still more obviously of this integrating character. For, in fact, the one mental conce[)tion here directly involves the other, and is only fully intelligible in relation to it. Each idea is to us only what it is on account of its opposite. In passing from the one to tlie other, therefore, tiie mind is simply com[)leting the complex image, one side of which is always the necessary correlate of the other. The same seems to hold equally true of the law of co-adjacency, as when a certain liouso recalls the friends we met — the conversation we had in it ; or when one event recalls another which happened at the same time In speaking thus of the pro- cess of re[)rodiiction as throughout of an integrating character, it may be necessary to guard against our being supposed to say that the mind necessarily impresses a wliole upon all the successive train of its ideas. This, on the contniry, we know it frequently ( ii.\r. IV. SKiT. II. i6o THE ELEMENTS OF THE CIIAl'. IV. SKcr. 11. • |i' does not do, the last link in the train having often no relation to the first as parts of a common whole. Mental succession is not unfrequently, as in reverie, a mere straggling array of scattered images. The integration does not proceed, as it is not necessary that it should, all along its course, but only from step to step. The general train may thus present a very incongruous mixture of ideas, while it has yet, j at every step, strictly obeyed the great law of mental I development. I " We may further observe that it is not necessary, as we might be apt to think from a first confused conception of the law, that the facts of a train of association should have previously co-existed in the mind. In some cases they have co-existed, and to this fact of their co-existence is owing their tendency to reproduce one another ; but more frequently they have had no such previous alliance in the mind. An object never before perceived may suggest an old ! familiar object; while again, an object frequently perceived may suggest, in different moments, very different and even quite opposite trains of thought. Were it not for this characteristic of the principle of association, the field of our knowledge would have been comparatively narrow, confined, as it must have been, to the relations which, from actual obser- vation, we had stored up in our minds. We would never have been able to get out of the past wheel or circle of our thoughts. As it is, the suggestive capacity, continually started by everything around us, is, in all active and cultivated minds, ever PSYCirOLOGY OF COGNITION. entering on fresh fields of intellectual interest, and acquiring fresh stores of knowledge."* Section III. KINDS OF KErRESENTATION. § 98. The simplest mode in which the representa- tive faculty operates is illustrated in reverie. Objects are presented before consciousness singly or in groups, without any particular order and without any con- nection with a place or a time in which they have previously been known. This mode of representation, in which phantasms are isolated from their deter- mining circumstances, has been called phantasy. Dreaming is a well-known example of it. Images come spontaneously into the mind, and are supposed to have a present reality. These images may be complete in themselves, but they are separated from the various relations in which they may have been previously observed. This phantasy, this simple bare representation of images, is the least complex, and, at the same time, the least perfect mode of representation. It usually takes place in a state of mental inactivity, as in reverie or dreaming, when there is no volimtary putting forth of effort, or in some abnormal condition, as fever or insanity, when the images of a period long past come up vividly before consciousness, although perhaps for years they had been dormant. Thus, in simple phantasy * Tulloch's Tlicisni, pp. 211-14. M l6l (IIAl-. IV, SKCT. III. ^:i I'll Hilt a Hij. :il : . i m !:|L ni HI' fH' f j! ;! »i f 1 ' H ■i . If • ( Miiwa Li 162 CMAl'. IV. 8i;CT. III. M< iiKiry. THE ELEMENTS OF THE tho mind appears to be, to a great extent, passive ; there is no voluntary effort to fill up the circle of knowledge connected with any particular phantasm. Since this imperfect mode of representation is usually found in quiescent, abnormal, or diseased conditions of the organism, physiologists have given great attention to it for the purpose of discovering the organic conditions upon which the power of repre- sentation depends. As, however, we are not at present interested in this question, we shall proceed to the consideration of a more perfect mode of representation, and one with whicli wo are more familiar. § 99. Memory is not the simple representation of phantasms or images before consciousness ; it involves that, and something besides ; the additional elements which it involves appear to be the following : — (1.) There must be Recognition; that is, the image at present before the mind is known to be the same as, although numerically different from, one pre- viously known. When we see the face of a friend whom we have not seen for a long time before, we recognise him — that is, we know that we have seen him before ; and in the same way, when an image of an absent friend presents itself to the mind, we recognise it. (2.) Memory necessarily involves the element of time. The very nature of recognition implies that the present act of the mind has a reference to some past time, and that the object recognised is believed to have been previously known. PSYCnOLOOY OF COONITrOX. Althouj^h there may bo many other cirtniniHtaiR'ca connected with an act of memory, yet these three which we have mentioned — the simple phantasm, the recognition, and tlie reference to a past time — appear to be all the elements which are essential to memory. § 100. Memory, as a form of representation, we have seen to be essentially an inte(jratiug process. Some image presents itself before the mind, and we recognise it — that is, we believe that we have known it before in connectio)i ivith a number of other mental objects. The act of memory is not complete until we are able to recall the other circumstances witli which the recognised phantasm was originally connected in our knowledge. To remember a thing, in short, is to posit the image of the thing in the midst of a greater or less number and variety of other images in connection with which we have already known it. We must be able to posit it in time, but as time is known to us only by a succession of events or images, tlie giving of a position in time to the object of memory implies an ability to say what events pre- ceded, co-existed with, and succeeded it. Hence, when we try to remember an event, we are satisfied when we are able to say that it occurred about the same time as, or soon after, another event with which we are more familiar. And the greater the number of the circumstances or events in the midst of which we are able to posit the object of memory, the more complete is the act of memory. These accompanying circumstances may be of any kind ; may be sensations of our own minds, actions performed by us or others, M 2 163 CUW. IV. .SIXT. 111. MllUOI'lf of i nuts ill time. $. $ 1 ■ w U • V i I' ^^ I ii il , t. t 11 164 THE ELEMENTS OF THE 'It ; I, f (;ilAi'. IV. srx'i'. in. in'thiiiif iiini'. objects existiiif,' in space, even arbitrary artificial si<;ns indicating time, place, or circumstance. § 101. There are, however, forms of memory in which the reference to time does not appear to bo essential. A student wishes to demonstrate tlie forty- seventh proposition of the first book of Euclid ; but he has partially forgotten it. He does not attempt to connect his partial knowledge with anything past. He looks at the figure and endeavours to lecall the relations which exist between the diftercnt parts of which it is composed. And a perfect memory of this proposition has probably no reference to past time at all, but is simply a representation of the lines and angles of the figure before the mind, with a clear perception of the relations existing between them, and of the conclusion which follows from the com- parison of these relations. Similar remarks might be made with reference to our memory of other systems of knowledge. There is also a form of memory which is involved in the acquisition of practical habits, from which the element of time appears to be eliminated. When a musician remembers a piece of music, it is not meant merely that the musical notes are represented before the mind's eye in their proper order, but also that he can, without hesitation or difficulty, strike with his fingers upon the proper keys, and produce in quick succession the sounds indicated by the musical characters. And, in this case, the want of memory consists in an inability to think of the par- ticular series of musical notes which should follow rs YCIIOL 00 Y F COON J TION, i6; or precedo some otbor reiiicaiberod parts ol' tlio pioco. Thus, porliap^, it would be more accurjito to con- sider recogmtion as the one essential characteristic of memory by which it is distinguished from simple representation ; and to add that, when the object of memory is a past event in our own lives, the act of memory involves also the positing of its object amongst a greater or less number of other objects or events related to one another in a past time. § 102. There is another mode of representation diflfering from simple phantasy in having a reference to time, and differing from memory in referring to future instead of to past time. This we call expecta- tion or prevision. In the process of perception this plays a very important part. The different qualities of which an object of perception is composed have been so constantly found in our experience united together, that when we perceive any one of them we expect to find the others. We have always found that the coloured globular body which we call an orange contains within it a pleasant acid juice and several seeds. Whenever we see an orange, we expect to find within it what our past experience tells us is likely to be there. Thus, expectation is founded upon memory ; and upon the constancy and invariability of the experience with which memory furnishes us will depend the confidence of our expectation. The perfection of expectation is prevision. The astronomer can predict with certainty when an eclipse of the moon will take place, because ( HAI'. IV. HKCT. III. E.rj)i'cf(l' tioit. 111 4» ^ • ii' :!:: ''!! i ^ iil ir il 111 Iil 1 '' i II i6G THE ELEMKSTS OF THE < HAi'. IV. bis calculations are fouuded upon a long series of accnnitelv observed and constantly and invariably recurring phenomena. The weatlier-casts of the meteorologist do not give rise to the confident ex- pectation produced by scientific prevision, because tlie phenomena observed are exceedingly variable and inconstant, and it is known that there niav be innumerable disturbing causes at work. In daily life the principle of expectation is of the greatest practi- cal importance in guiding our conduct. One of the forms of superstition consists simply in founding an expectation upon some sign or omen which is con- nected by tradition with the event expected. The sliii-htcst reflection miaht show the utter want of connection between the sign and the object of expec- tation ; but the association has been formed in child- hood through the instructions of parents or relatives, and even after reflection has shown that it does not conform to truth or reality, its power can scarcely ever be completely overcome. A reasonable expec- tation is founded upon the remembered or well- attested experience of ourselves or others. We be- come acquainted, for example, with persons, and have opportunities of observing how they speak or act in particular circumstances. We form an estimate of their character — that is, we construct in our minds a certain kind or class oi ideal actions which we expect them to perform in certain circumstances. Tho better we know them, the greater confidence have we in our expectations. Thus, in all the circumstances of life, expectation, reasonable or unre.'t'?ouable, is an ^•Pl iy PSYCHOLOGY OF COCIXITION. 1 6; important guide ot our actions; and our success in cmai. n ,.,. T 1 , Pi' t^KCT. IV. life to a great extent depends u})on the eareiuhiesd and ability with wbich our expectations are formed.* Section IV. KINDS OF REPKESENTATION- IM AGINATION. -CONTINUED. § 103. The power of representation possessed by the human mind is exhibited in a still inore im- portant form than any whicli we have }'et considered. Hitherto we luive studied the representing power iu its simpler operations, in merely i-ecalling iu their natural order the objects of our ])revious knowledge. We have now to study the power of representation as combined with various other powers and exert*}d in various interests. And in this form of tlie operation of the representing power, we shall see that tlie objects re[)resented are modilied and re-arranged in various ways to suit the design of the individual. This form of representation is usually called the constructive or plastic imagination, to distinguish it iVom the simple representation of ol)jects in phantasy and memory. Before proceeding to consider the most important special apjtlications of the imagina- tion, wo may refer to certain general principles of its operation. • Althon<,'li till' mnst essential clement of oxpeetation is a ni 'ndii roprojieMtiilioi' rel'erre CIFA!'. IV, SECT. IV. imaginntiun. Pootiy, painting, sculpture, music, and arcliitecture are the usually recognised line arts. In the whole of these the imagination is exercised in calling up and combining images in the mind fitted to express, or to excite, some emotion. Tiie artist exerts his skill thus for an {esthetic purpose of ex- citing jjleasaut emotions. But art is also frequently (employed to excite in the mind emotions of sub- limity, fear, horror, or disgust. In all cases the imagi- nation is exerted in the construction of an object, or the composition of a work, which shall be fitted to call forth in the mind of the observer the particular emotion or combination of emotions designed to bo produced. And, generally speaking, it is by the study of nature, and the constructing of the work of art after the analogy of nature, that the designed effect can be successfully brought about. The artist can only employ the materials which nature gives him, and whether he tries merely to imitate nature or to produce something better than nature, his imagination must be employed in moulding, re- forming, or idealising natural things. § 110. In poetry, the physical material with which i iw/n/. the artist produces his effect is language. But the words are only the signs of the mental objects of the }>oot's imagination ; and it is in the calling up and arrangement of these mental objects that the poetical imagination consists. Hence versilication, rhyme, and other mechanical contrivances are not essential to the poet's art. If the language employed is fitted to cull up the same ideas in the mind of the I )., ,'r t • m ) U U; I H 'U: 'I. i 174 THE ELEMENTS OF THE CHAP. IV. PKCT. IV. t fl li :M 11 Suhjeds of poctrij. hearer as in tlio mind of the poot, that is all that is required of it. The aim of the poet, then, is, by means of words, to conjure up before the mind of his hearer or reader, imac^es of such a natiu'e as shall excite the special kind of emotion which he desires to excite. There arc various species of poetry in which this is attempted, and perhaps it is difficult to find amongst them a common characteristic. But, generally speaking, it appears essential to the pro- duction of the effect that there should be a certain iUasmb produced on the mind of the hearer. He must be made for the moment to believe in the reality of what he only imagines. The true artist realises the products of his imagination. Hence a highly poetical imagination is sometimes thought to be akin to madness. "Lovers imd mailmen have such seotliing hraiiis, Such slmpiiig fabtasies, tliat apprclicnd Slore than cool reason ever conipi-ehcuds. The lunatic, the lover and the i)uet Are of iuiiigination all conijjact : One sees more devils thiiu vast hell can hold — That is, the madman : the lover, all as frantic, Sees Ileh.'n's heauty in a brow of Egypt : The poet's eye, in a fine frenzy rolling, Doth glance fi'oin heaven to earth, from earth to heaven ; And as imagination bodies forth The forms of things unknown, the poet's pi/n Turns them to shapes, ami gives to airy nothing A local habitation and a name." A Midsummer Night's Dream, — Act v. So. i. § 111. The most important objects of the poet's imagination are scenes in nature, historical events, facts of human life, different types of human Sc. i. PSYCHOLOGY OF COGNJTIuX. character, and the various objects of the unknown spiritual world. All these classes afford innumerable and infinitely varied objects suitable for the excite- ment of the most varied emotions in the human mind. It would be impossible within our limited i, space to enter into a full discussion of the questions which suggest themselves in connection witli tliis subject. But there are two types of the poetical imagination to which we must refer. One of these we may call the descriptive; the other, the dramatic. In the forintr there is an ability to describe scenes and events, it may be with great accuracy and great beauty, as seen from the poet's own subjective stand- point ; in the latter there is an ability to construct an ideal character, quite distinct from the poet's own character, and imagine the feelings, words, and actions suitable to that character. Bvron is an illustration of the first ; Shakespeare of the second. Byron's ' Childe Harold ' is admirable, because it is descriptive, and he was able to describe with elegance, and indulge in the most appropriate reflections regarding the objects of his description. Byron's dramas are failures, because every character is just himself disguised. Shakespeare was able completely, in his dramatic efforts, to divest himself of his own character, as it were, and assume tliat of the person whom his imamnation created. Thus he was able to construct a wonderful variety of characters ; and in every case he has ascribed to them the feelings, words, and actions which everybody will acknow- ledge as natural to these characters. In this 175 CMAV. IV. SKCT. IV. piii tii-al illiiKjilUl' tiuu. ; ■1 I it ! ■' j ; i i. ' ■ii 176 77//-; KUaiESTS OF riiF. CHAP. IV. SKIJT. IV. I'lraithiij mill ariilji- ture. wonderful power of forgettinj^ himself, and being: able to imagine how all kinds and descriptions of peojile ielt and would naturally act in particular circumstances, lies tlie greatness of Shakespeare. § 112. Tainting and sculpture differ from poetry in being more restricted as to objects presented to the imagination, and in emjiloying a different material as the sign of those objects. The poet can roam un- restrained in every field which his imagination can reach ; the painter and the 8Cul[)tor can represent only what were originally objects of sight. In a very primitive period of the history of civilisation — in Egypt, in L'abylon, and in India — the sculptor's art was emi)loyod in the reju'esentatiou of the national ideas of tlie deity. Tiie huge size, and the grotesque construction, of tlio ligures wliich have been preserved to this day, reveal to us the nature of the religious imagination of the people of these old days. The difi'erent parts of human and animal bodies, fearfully exaggerated in size and proportions, and strangely combined together, are formed by the artist into huge and uncouth figures, intended to express the qualities which the people attributed to their deities. In Greece, the painter's and the sculptor's art became more natural ; the imagination was exercised to pro- duce beautiful figures and features which should imitate, or even emulate, nature ; the exaggeration and the grotesqueness of tlie old artists were dis- carded, and art was cultivated for the salve of. grace and beauty. The artist did not merely seek to express with truthfulness the beauty of nature, but, PSYCHOLOGY OF COGMTION. / / 1(1 being )ti()n3 of articular (are. 1 poetry ed to the material 'oaiii uii- tiou can 'ei)resent n a very tion — in tor's art national rotesque •reserved religious s. The fearfully traugely ito huge r[ualities ies. In became 1 to pro- should geratiou ere dis- 3f . grace seek to ire, but, by combining the most beautiful forms which could be discovered into one ligure, or by idealising those condonations of features or (jualities which jire lounil in nature, he sought to surpass the beauty of nature in his imaginary hmii ideal. § llo. Music, lilv(; the other line arts, was origin- ally enlisted in the service of religion. ljik 4l^ # 6^ s^' * "^ A> «' '^^ 23 WEST MAIN STREET WEBSTER, NY. 14580 (716) 872-4503 178 THE ELEMENTS OF THE W J' m t ; ( HAl'. IV. >?KCT. IV. Aichiicc- flirt. mournful Boiemnities of the funeral procession ; anotlier to the measured tread of armed men ad- vancinG: to the field of battle. And the art of the musician is exhibited in adapting his musical com- positions to the nature of the emotions which he wishes to excite, or with wliich ho wishes his piece to harmonise. § 114. Tlie art of architecture originated in an attempt to beautify and adorn the temples of religion or the houses of the wealthy. There is, therefore, in this art a combination of beauty with utility. A regard to usefulness and stability, therefore, ought to govern the architect in deciding upon the principal parts of the building ; these qualities being secured, the imap;iuation is at liberty to add such lines and figures of beauty as may seem suitable. The art of the architect at different times has inventi/d a con- siderable variety of style in the structure and orna- mentation of buildings, for a description of which we must refer the reader who wislies to pursue the subject to the numerous works of professional men who have devoted themselves to the subject. We have now concluded our brief account of the different special modes in which the constructive imagination of the artist operates, and with one remark we dismiss the subject. The exercise of the imagination in the study, or in the construction, of works of art is fitted to have an ennobling and refining effect upon the mind. It turns awav the attention from gross, vulgar, and merely sensuous objects; and, if properly directed, cultivates those ) PS YCTIOL G Y F CO G XITTO X. 179 CHAP. IV. SECT. V. higher and purer emotions which give to Imman life its best pleasures and to human character its greatest excellences. Section V. KINDS OF REPRESENTATION — CONTINUED. IMAGINATION IN ETHICS AND RELIGION. §115. In practical life the activity of men is | 77irf7/,/co? directed to the attainment of some End. Tlie Ends which men propose to tliemselves are very various : pleasure, wealth, power, fame, and many others. But in every case the End of a man's life is the product of his constructive imagination ; it is an ideal composed of all the elements which, from his nature, he is led to think desirable. The ethical ideal must alwavs be constructed out of materials furnished by the actual. In our experience we enjoy many pleasures ; but we think of pleasures better and more lasting than those. In our experience we perform, or we witness performed by others, actions which we approve of, which we consider praiseworthy ; but we are able to conceive better, more generous, or more noble actions. In sliort, we are able in our imagination to rise, as it were, above our experience, and from what is to construct the ideal of ^vhat ought to he. We are not here concerned with the nature of the power by which we are able to perceive the ought or duty. That is a question of ethics. But we may examine briefly the nature of the process by which the ethical ideal is constructed. N 2 f \^ I*!. % V-' '{ t i "ii I 1 n : I! i i ^.l ■ , 1 t ; 'Im ! ■ i ! 1 ■ j! ■ ' ' 1 M ' ■M It it ! [ ir 1 1 i8o THE ELEMENTS OF THE CIIAl'. IV. SLCT. V. The ideal introduces couflict. Foynuition of ideal. § 116. In all men there are certain primary in- stinctive impulses and springs of action : appetites, desires, passions. A person who is completely under the control of these, who is governed by them with- out reference to the feelings or the interests of others, is absolutely immoral. To be moral implies that tliese natural impulses are controlled and regulated by the voluntary power of the individual with re- ference to some worthy end. But they will never be controlled unless the individual sees that their uncontrolled exercise leads to evil — that is, unless he sees that there is some higher good to be attained by controlling them. The conception of this higher good is the ideal which he forms. The general effect of the formation of an ethical ideal is to make one dissatisfied with himself, to make him feel that there is an excellence of character to which he lias not yet attained. There is thus a conflict produced between the actual impulses and desires on the one hand, and the ethical idea on the other, as to which of the two shall govern the conduct. The result of this conflict is of the most momentous imj)ortance to the happiness and welfare of the individual, § 117. With reference to the history of the forma- tion of the ethical ideal it is difficult to speak with definiteness. The ideal of one person is often widely different from that of another ; of one nation from that of anotlier. There can be no doubt but an ideal of some kind is usually formed by every one by means of reflection upon the comparative worth of different aims or obj( cts in life. But the greatest Pi .1 ■jj '•vrr^iwea mary in- ppetites, ly under 3m with- >f others, lies that regulated with re- 11 never lat their 3, unless attained s higher general to make feel that L he has )rodueed the one to which result of •tance to e forma- 3ak with n widely rom that ideal of one by north of greatest PSYCHOLOGY OF COONITION. influence is undoubtedly exerted by people or nations coming into contact with those who have higher moral conceptions than themselves. The power which a man of true moral worth sometimes pos- sesses in guiding the formation of an ethical ideal in the minds of others is very great. Thus, it is true in the history of morals that it is very slowly, and with great difficulty, if at all, that an isolated race can rise to a higher moral elevation; while the influence of an individual or of a nation possessed of high moral qualities upon a race not so favoured is sometimes enormous. § 118. The eflforts of the imagination in religion are chiefly exerted in constructing a representation of the object of religious worship. Amongst lower and uncivilised races the imagination is usually assisted by the mechanical construction of actual material idols or images. But the representation of Deity under material forms degrades our conception of a spiritual Being, and amongst all monotheistic races the representations of the Deity are mental. The idea of Deity which the human imagination constructs has varied greatly at difierent times and amongst different peoples. It is also a very complex idea — perhaps the most complex which can be formed. But the most important elements whicli have been comprehended in it appear to be the following : The Deity is imagined as the all-powerful and all-in- telligent First Cause, the Moral Governor, and the Universal Father. The first of these elements of the conception identifies God as the source and the guide i8i CHAP. IV, SECT. V. Idea of God. ■ii. ^M I- ) - I ! i 1 1 ' ! ,': i I, ) ! « P'. 1- l }•■ I •■ ,1 1 . I t «;;s>an'4i I: : 184 cirAP. IV. SECT. VI. rrpresenta' finv. ■I' i I ■ I I ] \i l,M f l<; THE ELEMENTS OF THE might mention in the series of representations wliich, in the minds of diflerent persons, are sugg( sted by particular objects. To different travellers going along a road or visiting places of interest, the objects presented to the eye will suggest to the mind widely different lines of reflection. The artist, on visiting the Falls of Niagara, will admire the grandeur, the sublimity of the scene; the practical uncultured American will think of the great loss of water- power which might be utilised in driving number- less mills. The followers of particular professions have peculiar lines of reflection naturally suggested to them by the objects of their knowledge. These peculiarities in the series of representation depend upon the circumstances of the individual — upon age, sex, country, education, social position, prevailing feature of character, and many other things Avhich might be specified. That which gives to this subject its greatest im- portance is the practical effect exerted upon one's character and welfare by the spontaneous series of representations which pass through the mind. The mind is very injuriously affected by continually indulging in thoughts of sensuous pleasures, by cherishing feelings of anger or unworthy suspicions towards others, by thinking always of difficulties and hardships and thus taking a gloomy view of life. And it should be remembered that there is a certain voluntary power, which every one has to a certain degree, and ought to cultivate, of regulating and controlling the representations of his mind. By PSYCHOLOGY OF COGNITTOX. 185 a voluntary effort one is ablo to bacisli from his mind evil and injurious reflections, and dwell upon those of a better and more ennobling kind. And the exercise of this voluntary power is perhaps the most important element in self-culture. There is scarcely any power which one can possess so valua- ble to him as that of self-control, and this not merely the control of external expression and action, but of the feelings and thoughts of the mind. § 122. In the constructive imagination, also, there are important differences to be noted between different individuals. And here, perhaps to a greater extent than in any other department of the human mind, we may observe inherited peculiarities. Poefa nascitur, non jit. The mechanical genius, the poet, the musician, the painter, the sculptor, and the architect — if they are not mere mechanics, but poets, makers, men of creative genius — are horn. They bring with them into the world the capabilities of becoming what they afterwards become, and what they could never become were it not for the in- born genius which they have brought with them. Kemarkable examples might be given of persons who, at a very early age, have exhibited powers in mathematics, in music, in poetry, in sculpture, which could not possibly have been acquired by education, and which must have been inherited. But from whom the inheritance has been derived, and how it is been transmitted, will probably always remain insoluble problems. CHAI'. IV. SKCT. VI. recnUiiii- tiix ill roii- xtntctlrt' imaijiitn- tioit. icS6 THE ELEMENTS OF THE ! ' ^ f'HAl'. IV. 8E0T. vn. Ahittnic- ti(m tli- neribcd. Ki'presen- tittion of abstract Kcnsations, Section VII. REPRESENTATION OF ABSTRACTIONS. § 123. It is frequently necessary to withdraw the mind from some of the qualities of objects for the purpose of giving undivided attention to others. This process is called abstraction. The quality or qualities to which attention is given are properly said to be prescinded from the others ; the mind is properly said to bo abstracted from the qualities to which attention is not given. In ordinary usage, however, this distinction is not attended to, and the quality singled out for sj)ecial attention is said to be abstracted from the others, and is usually called an abstraction. Tiiere may be abstraction from indi- vidual objects of perception, as where the colour or the figure of an object is attended to apart from its other qualities. And we have now to consider how the representative faculty operates with reference to these abstractions. § 124. Considering first the qualities of a body which correspond to special sensations, we observe that the representation can be effected only by the help of the special organ of sensation concerned in the original intuition. A colour can only be represented in connection with the eye ; a smell in connection witli the nose ; and so on. Thus, by the aid of the organs of sense, a representation may be made of particular qualities abstracted from an object. But PSYCllULOGY OF CO(.IMTU)S. tlioro is a series of so-called (jiialitics, consisting of extension, iigure, i)()sition, and other modes of space, which must not be confouiuhid with those qualities that are the corn datives of sensations. (Qualities that are the correlatives of sensations are represrntod by the aid of the one special sensc-orj^an with which they are p(H*uliarly cojinccted. Extension may be rej)res(>nted in connection with any sensa- tion located anywhere in the sensoriuni, but notably in connection \\\i\\ the sensations of colour and the tactual sensation. It is to be observed, further, that the connection in rei)rcsentation between the phantasms of colour and touch on the one hand, and the idea of extension on the other, is inse])arahle. It is impossible to represent a colour or a tactual sensation except as occupying some form of space. xVud in so far as any sensation is si)ecially located in any part of the sensorium, the same inseparable connection w itli some form of space is found to exist. We conclude, then, that we are able to represent the qualities of bodies which correspond to our sensa- tions apart from one another; that we can make abstraction of the colour, or the smell, or the hard- ness, or the taste of an object, and represent any- one of them apart from the others. But when we attempt to represent colour or hardness we are com- pelled to join some form of extension with them ; there is such an inseparable connection between the two that a separation, even in thought, is impossible. § 125. Let us consider now the nature of our representation of extension or space. Extension or 187 ClIAl'. IV. siicr. VII. . I -it I 1 88 ! 1 M f. f Ii^ TIfE KLEMENTS OF THE VMKV. IV. SKCT. VI r. (>J Hpnrr or txt< union. spftcc, considered apart from the objects wliicli occupy it, is undoubtedly an abstraction. Extension, we have seen, is the form of which tho colour, hardness, and other qualities of bodies are the matter. And the question arises, whether wo can represent tho form apart from tho matter ; we have already seen that we cannot represent the matter apart from tho form, and a little reflection will convince us that the reverse is equally true. The representation of pure space, or pure empty extension, is an impossibility. For when we attempt to represent space, we invariably do so by thinking of the possibility of moving through it. We think that, no matter how far we travel through space, there is still a possibility of going farther. And if we attempt to conceive a limited portion of space we must do ho by connecting it with some sensible boun- 1 dary, or some collections of qualities, or some pos- sibilities of motion. This impossibility of representing i pure space apart from the idea of some qualities ' occupying it, or some objects moving through it, I might be inferred from the nature of our conception ; of space. It is an abstract formed from particular ! relations of extension. But extension is the form of intuition, the form in which objective phenomena are I perceived. But the form of phenomena is not itself a phenomenon, and we therefore need not expect it to be capable of being represented as one. The doctrine which we have maintained regarding our representation of space does not affect the question as to the nature of its actual objective ex- istence. That is a question which belongs rather to rsYCiroLooY of coonitiox. metaphysics than psychology, and wliich, theiet'orc, wo shall not at prcatnit discus??. § 12o'. In considering tho possibility of represent- ing logical abstractions, wo must anticipate a little, and suppose the reader to bel'auiiliar with the nature ol tlie process to bo al'tervvards described. The great majority of the words in every language are the names of classes of objects — as man, triangle, tree, river ; and the question we have at present to con- sider is, how, if at all, can wo represent to our minds tlie objects indicated by words such as these ? And it must be remembered that there are in nature no tilings corresponding to these general names. There are plenty of individual men, tall or short, black, white, brown, or olive ; but there is no such thing as man in general as distinguished from particular in- dividuals. So there are triangles equilateral, scalene, right-angled, and so on ; but triangle iu general is unknown. A little reflection will show not only that such a thing as man in general does not exist in nature, but that it is incapable of being represented to the imagination. For if we attempt to represent what we mean by man to our mind, we shall find tlie representation assuming some particular form, and colour, and other qualities. We cannot help it. And in the same way of all other names which indicate classes of objects. It is impossible to represent the connotation of a general name, as for example, trian- gularity, without bringing in along with it, more or less definitely, the other qualities or parts belonging to some particular objects of the class. 1S9 CIIAT IV. HKCT. Ml. a hut Id I'- tioni'. i \^ !' 4. r V I rr T7 t ■if )i /M ' , I, » ; I 1 190 CHAI'. IV. SECT. VII. Difinilti/ Mati'd and ohviati'd. THE ELEMENTS OF THE § 127. It may be asked, tlieii, how are we able to iiiidcrstimd tlie definition of a ela.ss of objeets, as, for example — A triaiip;lo is a fiirure bounded by three lines? Into the definition tliere are not introduced any peculiarities belonf^infr to particular trianirles, and yet we are able to understand its meaning:. Tlie explanation of this is probably to be found in tlie relation between language and the oltjcct of tliought. When a word has become attaclied to a particular object or class of objects, it may frequently be used without bringing into the mind the tilings denoted by it. And especially when words have become very familiar, they are joined together in propositions, and the propositions are assented to, although there is in the mind no attempt to realise their meaning-. Thus a familiar pro])osition, such as, A triangle is a three- sided figure, is listened to ; it has been thoroughly understood long ago, and deposited in tln^ memory as something to be received without question; and, consequently, when the proposition is pronounced it excites no mental activity except a vague belief that it is quite correct. But if an attempt be made to realise a general name, or to understand a proposition in which a general name is the subject, there must be a repiesentation of a more or less complete and definite object. § 1 28. The employment of words indicating classes, or geneml qualities, or general modes of action, as if they represented real things, has led to many erroneous conclusions. And, consequently, it is important that words and propositions should be e able to cts, as, for by three ntroduced trianL'los, liiip:. Tliu md in tlio {■ tlioufjjht. partif'idar T be used ■? denoted ?ome very tions, and liere is in no-. Thus 3 a tliree- lorouglily memory [Oil ; and, )nn('ed it el let' that made to 'oposition ere must lete and o* classes, iction, as to many V, it is lould be PSYCIfOLOGY OF COGNITION. 191 frequently test(.'d by attemptinp^ to realise tlieir mean- ] f'Ar. iv. iiio; — that is, by attempting to form a representation j — '-- in the mind of the thinjrs whieh they denote. Foi I Jiculiailltl example, if such a coUocation of words be formed as, a square triangle, its iUef^itimaey would be at once seen by an attempt at representation. The ideas of squareness and of triangularity are ineongriious ; tlu'y cannot be joined together in the same rei)resentation. Thus the possibility of representation is an important test of truth. It must not, however, be aecepted as a test without certain limitations. There mav be re- presentations formed whieh iiavo no corresponding object in nature. The formation ol' a centaur or any other monstrosity is quite possible and quite common. And thus the possibility of uniting in a representa- tion any given number and kind of eh'ments or (pialities is no guarantee whatever of objective truth. But, on the other hand, the impossibility of repre- sentation is, in certain circumstances and cases, the only test of truth which we possess. For example, in the proposition, two straight lines cannot enclose a space, the absolute incompatibility between the re- presentation of two straight lines and that of an enclosed space is to us the guarantee, and the only guarantee, of the truth of the proposition. And we might refer to certain other sinq»le proj)ositions regarding primary objects of intuition in which inconceivability is unquestionably the test of truth. § 129. When, however, we take into consideration highly complex objects of thought, it becomes much more difficult to ai)ply the test. An apparent of iiln^fnu- tion. truth. Tlu l> .iUjncii. impossibility of representation frequently arises simply from want of experience. For example, a prince of ►Siam once found it impossible to conceive water becoming solidified into ice. Ignorant rustics can- not conceive the possibility of fish flying through the air. These, and other examples, show that there may be an apparent imjiossibility of conception arising from the want of having had the requisite experience, and that inconceivability must not be taken as a test of truth until it has been criticised and its nature discovered. § 130. We have seen that it is impossible to represent a general idea, as that of man, triangle, except in connection with some particular individual belonging to the class. And this impossibility is taken as a sufficient guarantee that the general idea has no objective existence except as found in indi- viduals. This is true of all general ideas connoted by general names, and formed by a process of logical abstraction. For example, one of the most abstract of all ideas is that of Being ; but it is impossible to represent Being exce^jt as a predicate of particular existing things, and consequently it is absurd to speak of Being as having any objective reality. Similar remarks might be made regarding other logical abstractions — such as, the Absolute, the infinite. The same impossibility of representation holds good with reference to them, and the same absurdity is seen in attributing to them objective reality. § 131. There is another fallacy connected with ^^ ses simply . prince of ive water istics can- rough tlio there may m arising sperience, 1 as a test its nature 3ssible to , triangle, individual sibility is fieral idea in indi- connoted of logical t abstract ossible to mrticular ibsurd to e realitv. ng other lute, the sentation the same objective ted with PSYCHOLOGY OF COflNITION. representation to which we must refer. Tiiere are certain uniformities in the operations of nature whicli, being observed, are collected together and expressed in what are called Laws of Nature. For example, it is observed that material bodies always show a tendency to move towards one another when obstacles preventing them are removed. Uut amongst the heavenly bodies, when there is no apparent obstacle to prevent a general collision, it is found that certain bodies — the planets — move in elliptical orbits round central bodies of a larger size. Now, by many careful observations the laws of the motion of bodies in free space with reference to one another have been discovered. Bnt these laws are merely ex[)ressions of the relations observed to exist amongst iJicnomena. And when we attempt in imagination to make a representation of a Law of Nature, we cannot do so except by imagining a variety of objects related to one another in sucl\ and sucli ways. To attribute independent reality to a Law of Nature, therefore, is illegitimate. And yet we frequently hear Laws of Nature spoken of as being causal agents, as iiroducinr/ the phenomena of whose order and mutual relations they are simply an expression. § 132. We have hitherto considered the possibility or impossibility of representation as a test of truth with reference to the actual or possible objects of our experience. But there are some tilings about which we speak and reason which never have been, and probably never can be, objects of experience. These o ^93 riiAr. IV. SIX'T. VII. r,ff(rs of S(ttllrr (i.< r< pi<- sviittd. lirpl-( !ii n- fdfinii Ijlainnl. I :: I 1, ii ■ ( ! 1 ' , i Hi » Ii 1 J K f 1 1 • ' 1 1 1 1 i 1 ^1 i 1 ' ■ ; i ig8 r//ii ELKMESTS OF THE (HA I'. V, SECT. I. Furtln r ■ xplaiiied. ox\)veHsed iv laugnage, we sball call Predication. Ill a certain sense, wo liave predication in the very simplest act of consciousness ; as when there is a con- sciousness of any simple sensation, there is a mental assertion or acknowledgment of tlie existence of that sensation. That a particular sensation — say of heat, or colour, or smell — exists, is the expression of the conscious act in which it is known. Lut this implicit assertion of existence regarding the simple objects of consciousness can scarcely be called predication as we must understand predication in its present con- nection. Another illustration will make clear what we mean. xVn object of pei'ception is before us ; it is yellow, heavy, tasteless, and of a rounded irregular figure ; the name ffold has been associated with it ; by a little experimenting we discover that it yields, and changes its form, by repeated strokes of the hammer. We assert, " This piece of gold is malle- able." In other words wo predicate a certain quality — malleability — of the object — that is, of the aggregate collection of qualities which we called gold. And our predication here means simply that the quality malleability co-exists with a certain number of other qualities to which there has been attached a certain sound, gold. Predication in this case is the assertion that one object of our hioivledge, a particular quality, bears a certain relation, that of co-existence or co- inclusion, to another object of our knowledge, an aggregate of qualities having a special name. § 185. If we take any other case of predication we shall find something similar. We see two sticks r.^iVJIOLOGl' OF VuaSJTJuX. 199 IS a Con- or two lines placed side by side, and wo jxTCfivc them to be eitliev equal in length or unequal. We predicate that the one is equal or unequal to the other; or that the one object of our knowlcdi^^o bears a certain relation, that of etpiality or inequtility, to another. Similarly, there may be two colours placed before us; we predicate that the one of them bears to the other a relation of similarity or dissimilarity. Ho, when one object of consciousness is observed to appear immediately before or immediately after another, we predicate that the one bears a certain relation, that of antecedence or sequence, to the other. Thus in all cases it will be found that Pre- dication consists in the ajjlrmation that one ohject of our thought hears or does not hear a certain specified relation to another ohject of our thour/hf. § 13(j. We must now consider the ground or grounds upon which predication rests. How is it that we are able to make a predication regarding the relation which two or more objects of our thought bear to one another? Is there any other mental act of which predication is the result ? A little examina- tion will show that there is. When wo observe two colours and predicate that the one is similar or dis- similar to the other, the act of predication is mani- festly the result of seeing the similarity or dissimilarity of the two objects. Before we can predicate two lines to be equal or uneipial, wo must i^erceive their equality or inequality. In other words, predication is, in some cases at least, fountled upon Intuition ; we intuitiveJij perceive certain relations to exist between CIIAI". V. s&.'T. I. tioii. Intuition, Hi I 1^ 1' r if ; I ^ \\ 200 THE ELEMENTS OF THE C'HAI'. V. .«K(JT. II. lufcrence. certain objects of our knowledge ; and as the result of that intuition wo predicate the relations. In other cases wo must admit a different ground for our predications. For example, wlien wo alfinn, " The exterior angle of a triangle is equal to tlio two interior and remote angles," this is not the result of immediate intuition. There are various comparisons to be made before we can recognise the truth of the predication. So, when we affirm that the earth bears a certain regularly varying relation in space to the sun — or, in other words, that the earth revolves around the sun in an elliptic orbit — this predication is by no means the result of intuition, but of a mental process of a very complex kind. The more or less complex process by which we are enabled to predicate rela- tions between objects of our thought which we do not intuitively perceive is called Inference. But, as a general rule, intuition and inference are combined in affording a ground for our predications. We intuits certain I'elations to exist, from which we infer certain other relations to exist, and predicate accord- ingly. The nature of inference will be explained hereafter; in the meantime, we must give some atteniion to our intuitions. Section II. INTUITION. § 137. That act of the mind which we have called Intuition is the immediate knowledge which we have PSYCHOLOGY OF cooxrirox. 201 ho result In other for our in. "Tho tho two result of uparisons ;li of tho rtli bears e to the !S around is by no I process complex ate rela- h. we do But, as orubined IS. We we infer > accord- splained '6 some ) called re have of any object of (consciousness. Thus consciousniss is co-extensive with intuition, and therefore it might appear that the term intuition was useless. But it is convenient to have some word to distinguish the knowledge given in consciousness from tlie know- ledge which is the result of inference, and tho word we have used appears tho best suited for that puii)ose. Moreover, consciousness is mon^ properly upplied to our knowledge of objects or 2ihe}iomena ; whereas wo have now to bring into prominence the relations between objects. For these reasons we employ tho term intuition in this part of our work to indicate the knowledge wo have of objects given in consciousness and the relations between them. And, manifestly, the simple objects of intuition arc identical with the objects of consciousness. A sensation, an idea, an emotion, any phenomenon of the mind, is given to us in an intuition. In our study of perception we have examined into the nature and kinds of sensations ; and now, leaving the consideration of the individual phenomena of con- sciousness, we must consider the relations between them as given in intuition. § 138. We have already seen that we have an intuition of the relation of Sequence existing between two phenomena, and that this intuition, when generalised, gives rise to our conception of time. But there is something else involved in this relation which is of considerable importance. The phenomena of consciousness are usually clustered together in a very complicated way, and CIIAl'. V. i^ECT. II, Intuition ix iiiiint' tlidti: luHudnhjt', Kinds of sequence. 't I 11 '<' l\ U\ r' ji ii ti I ■;; P"^ i ! i'"'i 1 ' m '' 1 1 1 ¥ if 1 11 i Ijjjj ..]. 202 (JIIAI*. V. HECT. II. THE ELEMKSrS OF THE soqiiciiccs frcfjiiciitly tako plac«.' in wlmt wc may (loom an accidental manner. For example, the sonnd of a bell rings in our ears; tiion wo hear a c'lirriagf! goin;^ along the road; then we see the postman coming to us with a letter. Now, tlusc various events may occur in any order, and it do( s not appear to ho of any importance in what onk-r tliey come, or whether they form a sequence at alh There is only an accidental sequence existing between tliem. JJiit take another examj)le. We see a Hash of liglitning ; a few seconds afterwards wo hear a peal of thunder; shortly after that rain falls. Now, the first two of these events cannot he reversed, at least in our experience they never have been reversed. We may have obsei-ved peals of thunder succeeding flashes of lightning at a greater or less interval of time, but we li;i ve never observed the iovmav iweceding the latter. Thus, there are sequences which, as far as our experience goes, are irreversible. There is another characteristic of certain sequences to which we must refer. Sometimes we may see a flash of lightning, but fail to hear the expected thunder ; sometimes we hear the thunder without having seen the lightning. The antecedent of an irreversible sequence sometimes takes place without the con- sequent, or the consequent without the antecedent. Ihit in other cases the sequence is invarialle. A nugget of gold is suspended by a string ; we observe tiie string cut with a knife ; the nugget falls to the ground. Here is a sequence which our experience tells us is not only irreversible but also invariable. ^ PSYCllOLOdY OF CUGMTJUX. 203 Tlie brt'iilviiiijr or looscninjj: ol'tlio throiid novor takes pluoo without the objcc^t falling to tho <;roun(l ; tlio heavy object never falls to the {^n'oiind as lonj:^ as the thread remains fastened to it, and entire. The full sifjfnilieanco of this wo shall seo afterwards; in the meantime, we note the diil'erent kinds of sequences. § 130. Another relation of whieh wo have an intuition is that of co-cviatencn. W(^ have already considered the part whicli tin's relation plays in orjfrinating our conception of space, and we need not recapitulate. Wo may hero observe that owv percep- tion of external objects usually comprehends a (complexity of relations of both sequence and co- existence. And, further, we remark that a relation of co-existence is a necessary condition of our being able to intuite the relations to which wo shall iiext turn our attention. § 140. The relation oi Lihencss and UnWceness is a most important object of our intuition. Wo ar(^ able to compare two phenomena of consciousness or two more complex objects of our knowledge, and to know by an act of intuition whether they are like or uidike to one another. We use the words like and unliko in a comprehensive sense, includin g under them various kinds of likeness or uidikeness, of which the most important are the following : — • (1.) The likeness or unlikeness which exists between two bodies considered as occupyui'j space wo call Eqiialitij or Inequalifij. Two lines being seen side by side we intuite as equal or unequal ; and so of two superfices or two solids. There is another ("iiAr. V. ttia'i , and i'li- Equal it If. ^ /■ 11} : : il 'S i ■^ .. 'fill • 41: i : 1: I 1\ 3 \ •> 204 CHAl'. V. SECT. 11. in hind; la ile4jrM. Dtrifvd and cuiu- phi£ rela- tion)^. THE ELEMESTS OF THE kind of likeness between superficial figures and solids called by mathematicians Similaritij, and con- stituted by certani i)roportions existing between the different parts of the figures. This, however, is not an object of intuition, and with it we are not there- fore at present concerned. But there is an inferior, and vairue, kind of likeness which we intuite when we compare objects which have a more or less resembling figure or outline. For example, , the general figure of one horse is somewhat like that oi' another, although there are many differences between them. (2.) There is a likeness or unlikeness perceived in the Nature or Kind of the objects of intuition or knowledge. One red colour we intuite to be like another, and to be unlike a blue colour. Any sensation of colour we intuite to be unlike any sensation of smell. And so of all objects of con- sciousness. The same intuition takes i)laco with reference to complex objects of knowledge, and to parts of which they are composed. (o.) We are able also to compare in intuition the Degree or LdensUi/ of objects of consciousness. There are many things agreeing in kind but differ- ing in degree, and the perception of this agreement or difference in degree is, in the case of simple phenomena of consciousness, a matter of intuition. § 14]. The relations to which we have referred in the preceding paragra[>hs ajjpear to be those which are primarij ; but there are many other relations of which we ususally speak which may be i ' PbYCnOLOaY OF COGXITIOX. 20$ rediicod to one or other, or some combination, of tlu' precedinir. AVo speak, for 'example, of the relation between the siirn anave now established the fact that we intuitc a relation between relations. Section' III. DErENDENCE OF PltEDICATION UPON INTUITION. § 1413. The connection of Predication with Intui- tion is not an arbitrary or fortuitous connection. A certain intuition having taken place, tlie predication which follows from it may not be this, or that, oi- somethint^ else, according to choice; but there arc certain laws which govern us in founding mental assertions upon intuition. These laws mav be verv bi'ielly stated and illustrated. We have before us various objects of intuition ; they may be sensations, they may be objects of j)erception, they may be rela- tions, or anything else immediately before conscious- ness. Let us indicate them l)y the first letters of the alphalxit. We intuite the object A ; it is necessary for us to predicate, " ihis is A ;" it is imposstUe for us to predicate, " tliis is not A." This h\w of thought is usually known as the Axiom of Identiii/, and thus expressed: A is A, i.e., everything /« n-hat it is. Again, we intuite a certain relation existing between A and I). Upon this intuition is founded the predi- cation "A is B;" and it is impossible for us to predicate ''A is not ]>." This is usually called the Axiom of Contradiction ; and its formula is, Predica- tions opjwsed contradictorily to each other cannot loth I ; suffieioiit we intiiitc ruiTiox. itli lutui- ction. A rcdieatioi) i* tliat, or tliere arc g mental V be very before us ensations, y be rela- :'oiiscioiis- ers of tlip necessary hie for u.s lioiiglit ]\s md thus ct U is. between le predi- 'r lis to lied the Prcdica- 'Hot loth PSYCnOLOGY OF COdXITIOX, 207 hr true. Tlie one or tlie otlier must be fal, by observation abstracted certain specified qualities in the possession of whi(di a number of objects agree, these qualities taken t(>gether form a kind of mental object ; in the act of representation, although wo may not be able to banish altogether all the other qualities of the bodies, yet we give to them peculiar prominence ; we attribute to them a kind ice to the ; a number , ascertain a certain attention, is quality, ;o them ii v^ a class ; Thus, the to ckisses, s that AVe )me speci- s tliere are ion : h'rst, Nvliich lias »n of these "tile name, eralisation f that our e qualities ith wliieh be found, must (lis- ILavintJ^, n si)eeilied lumber of or form a :'sentation, )getlier all ^e to them !m a kind rsYCiioLoor of coax in ox. 1 1 of separate existi.'nee, \vhi(!li, a-;hou,i2fli no doubt objectively fictitious, is mentally V(\i\. 'i'hesc ab- stracted qualities thus mentally unified wi' call a Concept. Now the question arises, upon what prin- ci})le is it that we choose certain qualities of objects for abstraction and unite them into a Concejtt ? § 11!>. ?n answer to the question ja-opos 'd, it is, in the iirst }»lace, manifest that no qualities need be chosen except such as are possessed by all tin; ol>j(,'cts concerned. If we can at all unite objects into a class it must be by means of something which they possess in common ; some (juality or qualities in whieh they all agree. Thus, we liave one prinei[)le at least to guide us in the fornuition of a concept. Xothiitf/ can form a ikiH of the concept which is not possessed hy all the ohjeets. This principle excludes all those qualities with reference to which the individual objc^cts differ from one another. Here, again, another question presents itself. Are all the qualities in which objects agree to be includ(jd in the Concept ? In order to answer this question, we must consider the end for which c'eneralisation is undertaken. ( KM'. \ Fontuiiio:! of II fiiii- (■( l)t. CoDtlllliil I^ 150. The reason why we collect obiects into /'""//'" {/>'< 1 1 t ( fl S, clashes is that we may know them better. Diit in , this connection, more complete knowledge does lujt I mean a more perfe(;t knowledge of the qualities possessed by each individual. Our knowledge of classes is made more comidete by our beinii: able to compare them with other classes, and know in what respects they agree and in what resj)ects they differ from them. Hence, when we wish to have an r 2 f i I -i| 11 I I ( i\. i! if iifl l! I 4 ■ui 212 t MAP. V. SIXT. IV. THE ELEMEXTS OF THE aocumto knowled^^o of a class, it is not suniciuut iiieroly to collect into a mental nnity all tlitMjualities in wliich tlie objects of the class agree with one another ; ^ve must also consider in what qualities this class clilf'ers from other co-ordinate classes. The ])oints of difference are manifestly of great iinjxjrt- ance, because it is only by these that there can be ;» distinction made between the class in hand and other classes. Thus, we have here two collections ol qualities to be considered; those in which all the objects of one class agree, and those in which this class differs from other classes. For the sake of clearness let us suppose, to 1)0 qufiliticspos- Kssc'il ill coiiiiiion l)y all the objects ot' the claa.s. A, and h (I f h I m to be quii'.itk's pos- sc^.sfd by all the objects otthe cluss. i; Now, if we formed our concept of the class A without comparing it with other classes, we should include in it all the agreeing qualities a, h, c, &c. But when we compare the two classes A and B, we iind that they af/ree in the possession of the qualities h, cZ, /; and they differ in that A possesses a, c, e, which are absent from B ; whereas B possesses k, /, m, which are absent from A. Consequently, for the jnirpose of distingiUsliing A from B we must reject from the concept of A those qualities in which A agrees with B, viz. h, d, f; and we must include in the concept of A the qualities a, c, e, in which A diffen^ from B. Thus, for the purpose of distinguishing one class from other classes, special attention must be u. rSYCIIOLOGY OF COGXITJOX. SK.( T. IV irivcn in tlio Ibrniation of tlio foucopt to those mxi. \. ((iifilities wliit;h constitute tlio dijfo.rentUn botwouu it unci other co-ordinate chtsscs. § l."il. Are, then, all the points of ai^reemont F"r.u to be rejected rhs.-. from tlie concept of A ? If our object were nnn-ely to distinguish A from B, wo should reject tlieni. ])Ut as we wish to systematise our laiowlediie, to brinjjj all tlio classes of objects into relation with one another, the points of agreement between classes are mani- festly of great importance. For, if we consider as objt^cts the lowest classes which we have formed, and observe the points of agreement between them, we shall be able to form a higher class, comprehend- ing all these lower classes in the same wav as thev comprehend individual objects. And this process of classification may evidently go on, until all tli(3 objects with which we are acquainted have been combined together by virtue of their j)0ssessings()me- tliiiig in common. Now, in order to ccmnect any particular class with this system of classes, it is m^cessary to know not merely in wliat respects it differs from other co-ordinate classes, but also bv virtue of what qualities it is comprehended under a more general class. And these qualities, called generic, must, therefore, be united in the conc(3pt to the differentiae before spoken of. TIius, the concept of any class must comprehend the generic qualities, or those in which the class rese;jiWt's other co-ordinate classes, and the differentiiB, or those qualities which distinguish it from these classes. ■ K -l I, t 1 li: > J Lli I I ! i' I k i 11 i! li [.r^Rii 214 CIlAl'. V. r^i:CT. IV, II ud (K-i !- ill iitiil ijIKliililX. I THE ELEMENTS OF THE § 152. ITavinj^ coiisiderccl in genenil tlie consti- tution of the conoopt and tlio process of the mind ii, forming it, there is a question of importance connected with tlie nature of chiSvSes. Have chisses only a mental existence ? Have thev an existence oidv in the concept by which the mind binds them together? li they have not, then one concept, provided it be constituted as we have shown it sliould be, will be just as good as another. H the difler(aiticC of a class are all duly observed, and included ahmg with the accurately known generic qualities in the con- cept, these differentia) and generic qualities being discovered only bv the test of difference and airree- ment, tlie concept thus formed must be unexception- able, lint it is actually found that men of science, in constructing a classification, select fr(jni amongst all the points of difference and agreement certain qualities which they think to be of greater import- ance than others. They frequently reject from their definition of classes some qualities which by reason of agreement, and some which by reason of difference, should be included. An ilhistration will make plain what we mean : Fishes < a. live in water. }). are vortebratcd. c. ol.tain oxygen fm- tlifir blood from the water. (7, pictpc 1 themselves 1.1 V lins. 11. are ovipar /. have a Ion ous. rouni 1- ed figure fitting thera for easy motion in water. Whales - a. live hi water. }i, are vertel>rated. c. obtain oxygen for blood by breath- ing air. d. move by organs like fins. li. are viviparons. /. have a fish-liko ti.irure. rsrcnoLoar of conNirioN. 215 s lie consti- o mind ii; coDnet'tf'd only u only in together ? led it be e, will bo ti.'u of a long uith the con- ies beincf 1(1 agree- 'xcopfion- i' science, amongst t certain r import- om their )y reason ili'erence, nenn : r'iitcr. ■Itmtc'd. xygen for L»y breath- y organs irons, flsh-liko Now, comparing the lists of (jualitios possessed by fishes and wliales, wo see that the qualities marked a, /;, d, and / are identical or very similiar ; while the qualities c and e are different. And the (pies- tion is, are we to include whales in the class Fisii ? The }»oints of agreement are numerous. And if one quality were just as essential as juiother, wo should probably come to the conclusion that a whale is a fish, as it was long believed to be. J hit men of science tell us that the points of differeiu'e to which we have attached the letters c and e are of vastly greater importance than such qualities as a and /; and they make these points of difference essential, and some of the points of agreement accidoital, and consequently conclude that a whale is not a iish. Now, upon what principle is it that the qualities c and e are considered essential and included in the concept of a whale, while the qualities a and /are not ? How do you know the essential attributes of any class ? § 153. A great variety of answers have been given to this question, and it would take us beyond our limits to enter upon a description, or criticism, of the different theories which have been held upon the subject. The determination of what are the essential qualities of classes is no duubt to be accomplished l)y a comparison of many objects and an extended obser- vation of the relations existing between the qualities of objects. Those qualities of objects u-hichfrom their nature or uniform lyresence appear to determi)ie a great many other qualities, are naturally looked upon as (II.M'. \, .sKtT. IV. Whitt I tin - xfilufis ('.-•>■( II til! I qualili'ts ' ■f ' i1 I 'If 11: m^M 2\6 THE EL KM E XT H OF THE CIIAl'. V. HIXT. IV, \<(uir^. being essential. The possesi^ion of vertahrw by an animal, for example, nmst bo considered an essential quality, because we observe that it is the j^round upon which d('pend a p;reat many qualities that distinguish a vertebrated from an invertebrated animal. The principles upon which the selection of essential qualities depends are, however, a matter of science rather than of })syc]ioh)gy. But it is of importance to observe hero that we have established the fact of the objective existence of natural classes of things. There is a reason in the nature of things them- selves for their being brought together in classes. There are essential qualities comprehended in objects ; and it is only when we make our concepts to comprehend the same essential qualities that we have an accurate knowledge of tlie objects. A concept is true only when it comprehends the essential qualities of the class from which it is derived. § 154. We now give some attention to the names which we give to the various classes of objects that we know. The study of the science of language has brought to light many interesting and important facts connected with the application of names to objects. The simple names which primitive peoples give to the objects of their knowledge are usually expressive of some striking quality possessed by the objects. A river, for example, may be called the rimning thing ; the sun is named from its shining quality ; the stars from tuinhlingy or perhaps shining. A name which is at first significant of some striking '>>•«? by an ti esseutijil ound upon listingnisli Tli( nul. 1110 essentiul of science nportanco ho fact of of things, gs them- n classes, inded in ' concepts ties that objects, ends the ich it is he names eta that uage has nportant ames to peoples usually i by tho led the shining shining. striking rSYCnOLOGY OF COdMTJON. (jiiality or action possessed or performed by an indi- vidual object is afterwards apj>Ii(Ml to other obj(!cts possessing a simihir quality; aufl thus arises the lirst rude classification. Now, it must bo observed that tlie name is attached to the ohjects individually ; Ijccomes so associated with them as to form, jis it were, one of their qualities. 'And upon its first apjilication the name expresses the concept whic^h tho namii-giver had in his mind when he invented the name ; that is, expresses the quality which, to his mind, was most striking, and therefore most important. But, as know- lodge increases, the nature of the concept changes ; other qualities of the objects are discovered >\hieh are found to bo of greater importance than those first observed ; but no correspijnding change takes place in the name. Thus the natural class and the name are constant, while the concept is variaUe. And the question arises, what is the psychological significance of tho name ? § 155. It is usual to say that a name denotes objects and connotes attributes ; and it is usual to assume that the objects denoted are the objects of the class of which the attributes connoted are the essential attributes — that is, tho concept. Now, it is quite correct to say that the name denotes to all minds the objects of the class with which it has become asso- ciated; but it is not correct to say that the name connotes the attributes of the scientifically-formed concept. We have seen that the concept is a very variable mental object depending upon the knowledge and mental habits of the individual in whose mind it 217 cii-vr. \. HA1\ IV. Dcnntntion innl coiDHf latum. . 1 I! -I': II !l| ;• :1 >^ 11 m m 2l8 rJlE h'LEMEXTS OF THE CHAT. V. si:cT. IV. is formed. And, moreover, the concept is never represented in the mind Avitliont bringing along with it otlier accidental attributes forming no part of itself. And unless we arbitrarily restrict the connotation or meaning of a name, we should liold that it connotes all tiie attributes essential or accidental which it is the means of bringing before consciousness. Thus, it w'ould be very difficult for any one to pronounce (jr hear the word Jhh without thinking of the quality swimmin,' in the ivater, which is an accidental one. And it is in only a small number of minds that the sound of the word fish would suggest the quality of u-afer-hreathinrjf, which is a constituent element of the concept. Thus we should say tliat while the denotation of a class-name is invariable, or varies only in consequence of some change in the class, its meaning is, in different minds, exceedingly variable, depending not only upon the variation of the concept, but also upon the introduction into the mental image of a variety of accidental qualities. In consequence of this variability of the meaning of names, scientific men have, to a great extent, ignored the ordinary names of common language, and invented a scientific vocabulary whoso words should connote only scien- tifically-formed concepts. Thus, the principle is recognised that, in a scientific interest, the names of classes ought not only to denote the classes, but also to connote exclusively the attributes of the concept. But it remains equally true that in the ordinary affairs of life the names which we use have a very variable meaning, but are used to denote something psYCfioLoar of cogxittox. 219 t is never aloiif^ with lit of itsolf. notation or t connotes ivhicli it is Tlius, it mouncc or le quality lental one. Is that tlie quality of 'lenient of while tlie k^aries only class, its y variable, he concept, ntal image ►nsequence I, scientific i ordinary I scientific nly scien- ■inciple is names of s, but also } concept. ) ordinary re a very Bomethiu'j: which IS jiiactically iiivariuble, a really existing chai'. v. cla^s. 1 § li')C). A great deal of confusion has been caused I c.mu^nl by the application 01 the epithet //e^^eraMo the names /jj^,,, which liaA'O become associated with classes and to the ideas, as they are called, which we i'orm of classes. It appears to be assumed that the result of the process of generalisation must be itself ^eHcraZ; and the question has been long discussed, where is the assumed generality to be found? Kealists have lu'M that there is a general idea existing in nature; con- eeptualists maintain that generality is to be found only in the mental concept ; nominalists contend that nothing but the name is general. The truth is, we might as well speak of a square circle or a green smell, as of a general idea or a general name. Every ccmcept which we form is an indiridual collec- tion of qualities; every name which we utter is an individual sound. The name has become associated in our minds with certain similar objects which, in consequence of their similarity, we think of as iorm- iug a class. The conc(q)t consists of a number of qualities which we have observed to exist in all tlu' objects belonging to the class. The name is predi- cable of all the objects of the class, and, therefore, if we insist upon using the word general, we may say that the aj^plicatioii of the name is general. The qualities of the concept are prcflicable of all the objects of the class, and, therefore, we may say that the qualities nqu'esented in the concept are generally or universally found in the class. And, in fact, it is ;t :; t ii f '■• fi \A ■i : r 220 CHAl'. V. >K(;t. IV. Drfini- tion. Division. THE ELEMENTS OF THE the universal presence of the essential qualities in all the objects of the class which is the ground both of the general application of the name and of the formation of the concept. And, consequently, that which we mean by a name, and that whicli we repre- sent in a concept, has a real existence only in the objects of nature. § 157. The exposition in language of the qualities of a concept is called Definition ; the arrangement in subordinate groups of the objects denoted by a name is called Division. But it must be remembered that the definition is accurate only when the concept is true. For a definition to be correct it is neces- sary that the concept of which it is an expression should comprehend the essential qualities of the class; if the essential qualities are not known, if the class is recognised only by certain accidentiil superficial attributes, a correct definition is impos- sible, and we must be satisfied with such an in- definite description of the class as may be within our reacli. The important point which we wish to bring out here is that a definition, to be correct, must conform to objective existence ; that this conformity is brought about through the medium of a true con- cept ; and that, unless the concept correspond to real existence, a correct definition is unattainable. Divi- sion is just the reverse process of classification. As, by the perception of mutual agreements, we unite objects into classes, so, by the perception of mutual differences, we separate classes into subordinate groups. rSYCIIOLOGY OF COGNITJOX. O O 1 qualities in ground botli and of the uently, that ;li we repre- only in the he qualities rraiigement noted by a 'emenibered the concept it is neces- expressiou ties of the t known, if aceidentiil 1 is impos- ucli an in- bo within we M'ish to )rrect, must conformity a true con- ond to real ble. Divi- ition. As, , we unite of mutual ubordinato The rules of both definition and division are given in logical works, and these rules assume that we are always able to test the accuracy of a definition or a flivision by means of intuition. By intuition — that is, by direct observation — the concept is formed, and the class is determined, and when we attempt to dahorate concepts and classes into systems, it is only by reverting to intuition that we are able from time to time to test the correctness of our systems. The limitation of the sphere of logic, therefore, simply to the exposition of the nature and relations of concepts, without any reference to the truth of those conce[)ts, is, judged from the pyschologist's point of view, a blunder. We are not satisfied with cmisistencij amongst concepts which may be crude, or erroneous, or baseless ; we must have our systems of science continually tested by a comparison with the truth of nature, otherwise they are simply castles in the air. Consequently, it is unwise to^ separate the sphere of logical thought from that connection with the real world which is afforded to it in the continually possible exercise of intuition. Section V. PREDICATION AGAIN. § 158. We have seen that i'redication is the mental assertion, expressed in language, that one object of thought stands, or does not stand, in a certain relation to another object of thought. We C'llAl'. V. Sl'XT. \. J'l-'dirn- tion d' - fcrih' d. 'li ili; i ; ' '■' (1 i 222 THE ELEMEXTS OF THE I i! >Vi i^l' CU.W. V, Sonify Accidintal co-''xiKt- eiK't X nil joil'.i (1 ill pi( (llca- tt-oH. liave seeu the dependence of predieation ii})()ii intuition, and the part whicli it ])h\ys in tlic forma- tion of tlie concept. And before proceeding to consider tlie more comjilex processes of thonglit, it will be desirable to understand morefnllv the naturt^ and kinds of predication in itself. Predication \^ founded upon a union in consciousness of tiie two objects of thought of wliich the one is predicated of the other. The union in consciousness may correspond to an external objective imion, or it may not; but a subjective union there must be, in order to render predication possible. The terms of tlie predication, the things between which the I'elation is afOrmed to exist, are called Subject and Predicate respectively. 8ince a union in consciousness is a necessary condition of predication, it follows that any propositicm whose subject and predicate cannot be thus uidted must be unnieanini*' or false. If wo assert in words, " A cii'cle is a triangle," and attempt to think together in consciousness the subject and predicate, we shall at once see that, although a ]>ro- position has been constructed, no intelligible pi-edica- tion has been made. IMiere are, then, what we may call 'iiiijjossiUe predications ; wdiich are such tliat the mind is incapable of bringing together the sul)ject and. i)redicate into the relation which is asserted to exist between tliem. § 159. Again, th(."re may be objects of knowledge united together in consciousness, of which the one cannot properly be predicated of the other. For example, we may have in consciousness together the rsYcnoLOGY OF coayiTJox. 223 at ion iipoii 1 tlic forma- )Coo(]ing to thought, it y the Dutur.' odicatioii is of tiie two 1 lii-i'dicatcfl usiioss may 1, or it may he, in order 'riiis of tlie the relation id Predicate nsnes.s is a )\vs tliat any i cannot be -Ise. If ue md attempt sul)jiet and :)ug]i a ]>ro- ble prediea- lat we may eh tliat tlio the t-uhject asserted to knowledge eh the one >ther. Fur Dgether the (HAT. V, SI.(.T. V. sweet smell and the red colour of a rose; but it would be absurd to predicate, the latter of the foruier. The only way in which we can form a predication is to make one of these qualities a predicate of ^\hich tiie whole aggregate of qualities, along with the name rose, is tiie subject. I'lnis, when we speak of objects of perception, we invariably make the complex objectilied group of qualities the subject, and some one or other of the qualities the pi'edicate. Now, if we have in the same moment of consciousness a sweet smell and a red colour, it might appear just as reasonable that we should predicate the co-existence of these two qualities as the co-existence of one of them with the aggregate of qualities constituting the rose. But this is not so, and the reason ap[)oars to be tliat the aggregate of qualitit.'S has come to be looked iq)on as having more than a relation of co-existence with the single quality which is predicated of it. The aggregate of qualities is regarded as an ohji-.d, a united whole, of which the single quality is a constituent part. There is a permament and indissolubh; connection between the qualities, which is not truly expressed when it is predicated of them merely that they co-exist with one another. And this permanent objective connec- tion is the reason why the whole aggregate is usually made the subject of predication. § 1(30. We have hitherto been considtiring i)re- dication as concerned about individual objects ^'^^ .,,„,-dhi,, thought and the relations existing between them. co/resentation vould spon- ! similar to iVe are then "^ PSYCHOLOGY OF COGNITION. 227 brought down to the third possible meaning, which wo believe to bo tlio psychologically correct one — that the subject is primarily denotative and the predicate connotative ; and the assertion is tlint tlio quality expressed by the predicate is found in all the individuals denoted by the subject. § 103. We take another predication, " White is a colour." Now, it might appear at first sight that the subject here is a quality and the predicate a class-name. And if they were not connected as they are in this predication, this would be quite correct. But when we ask ourselves what we mean by the proposition, we find that it is an attempt to answer the question, " What is white ? " In other words there is something expressed by the word " white " which we wish to understand; we make a mental object corresi)onding to the word, and we affirm of it that it possesses the qualities possessed by other objects of thought to which we give the name " colour " — the qualities, for example, of affecting the eye, revealing external bodies, and so on. In this case a quality is made the subject of predication, but the quality is thought of as an individual object of representation, and its concept, or a part of its concept, is atKrmed in the predicate. That this is the true meaning of the predication will appear upon a little reflection. If we attemjited to explain to ourselves or others how or why we say that " white is a colour," we would never begin by saying that '* there are various colours, such as red, and green, and blue, and violet, and white is one of the class." I Q 2 CHAT. V. SECT. V. jin ilicd- lion. \\ ■• \ 228 THE ELKMENTH OF THE CHAP. V. SECT. V. !M Genus 2>redic<(te(l of siiicies. Oil the otlier liaiid, wo would cxi)laiii tliat " a colour is something which produces a certain impress'ou on the retina of the eye, and apjioars to be caused by li^dit beinnj variously reflected from external bodies, and as white possesses these qualities wo say that white is a colour," or something like this. Hence it ai)poars that, even in this case, the subject is an object of thought from which, for the time, connota- tion is excluded, and that the predicate is naturally and primarily a concept or collection of qualities affirmed of the subject. § lG-1. Let lis now take a predication in which both subject and predicate are class-names, " Pigeons are birds." Here the denotation of the predic\\i this can be it? significance onJj if it be ^n-imarily cunnotative. It i rs YcnoL a y of co n xi no y. 22^j t " a colon ]■ prcss'ou on caused by iial bodies, ^e say that Honco it bject is an e, coDnota- s naturally f qualities I in which > " Pip:eoiis )redicEcr. V. EjTi d of jirc.ridinfj (;onvtr, to systematic science. There may be possessed by a man a great deal of knowledge which can be of no use whatever, in consequence of inability to bring together into one view related facts, to sec their significance, and to give them their proper place in the system of knowledge. Thus, the knowledge which many possess, although very extensive, is a perfect chaos, a jumble of confusion, and of no prac- tical use in the guidance of life. To reason with a man frequently means nothing more than to point out the relation between different things which he already knows, and thus bring into order what was before confusion. There are to every man hundreds of " open secrets," facts related in particular ways which relations he cannot see; and it is the function of what is commonly called reasoning to convert this chaos of confused facts into a cosmos of order and harmony, so that men may see clearly what has always been under their eyes, and understand clearly the relations and significance of what they have blindly perceived. This discovery or pointing out of the true relations between tilings already known is not what we mean by Inference, although it very often assumes the form in jvhicli true inference is naturally expressed. It is made, also, still more closely to resemble inference by being frequently forced by logicians into the artificial forms of the syllogism. : ■ . 1 . \' H . ;, 1 ■ i \. i 236 THE ELEMENTS OF THE CHAr. V. SECT. VI. ' 'li, ii & Erroneous tionx. which is assumed to be the universal type of reason- ing. To make clear the true psychological nature of the process which we are describing we shall examine some typical examples of it. § 170. We observe, in the first place, that mistakes are very apt to be made in the classifying of the objects with which we are acquainted, and a great deal of what passes for reasoning is simply an attempt to assign objects to their proper classes. There are many popular classifications which are erroneous in themselves and lead to other errors, and an important duty of scientific men is to correct these erroneous classifications. From our study of the formation of classes we can understand the manner in which a correct classification it to be effected and an erroneous one is to be avoided. It is only by the possession of the Essentia of a class, or at [least of some universal characteristic of a class, that anv object is to be referred to that class. Suppose, for example, that a person ignorant of natural history were to assert that whales belong to the class /s/i, his mistake would be corrected by informing him that whales do not possess the essential qualities of the class fish — they are not water-breathing or oviparous. Supposing him to know the principle of classification, he would immediately see that his predication regarding whales was incorrect. And upon discovering, or being informed, further, that whales are viviparous and suckle their young, and that these are the essential qualities of a class called mammal, he would at once refer them to that class. PSYCHOLOGY OF COGNITION, 237 Thus, in order to effect a correct classification, it is j chav. v. SECT VI necessary to know by observation or instruction (1) | '. — l what are the essential or characteristic qualities of \ some class in question, and (2) whether tlio object in j question possesses or does not possess these qualities i or characteristics. Knowing these two things, the j mind at once refers, or does not refer, the object in ! question to the specified class. | § 171. The preceding example, which illustrates Thi ^yUo- the process of classification, when put by logicians 'th^imt into their favourite form of the svllopiism, appears as ; •'"''"' ^l^,^^ '• All fishes arc oviparous animnls : i K''"''"'"'"^'- Whales are not oviparous animals, . * . Whales are not fishes." follows :- We have already pointed out that the predicates of propositions, as a rule, are connotative, and that, therefore, it is psychologically incorrect to give them extensive . quantity. The first two of these propositions therefore ought to be : — " AH fishes are oviparous ; Whales are not oviparous." But, these two propositions being taken together, it becomes impossible to classify whales with fishes, and, consequently, the mind asserts — Whales are not contained in the class fish. Now, it must be observed that this is not an inference in the proper sense? of that term. The so-called conclusion is directlv seen tlie moment that the essential qualities of whales and fishes become known. If a boy have before him a number of marbles, and mixed iip with them a number of hazel-nuts, he sees at a glance that the ■ p • I .„:, i 9 238 THE ELEMENTS OF THE w m I ^ ' I: ^ a i CHAP. V. .SKCT. VI. I neon - (jruouH pre- ilicateH. \ latter should not be classified with the former. The i only difference between this case and the previous i one is, that the qualities which make it impossible to ' classify the two sets of objects together are more ; obvious. § 172. Again, it is a principle of consistency be- , tween predications that two incongruous predicates 1 cannot be attached to the same subject. To assert i " The figure A is a square," and " The figure A is a I circle," is a mental impossibility ; and in practice the only difficulty is to see wlmt predicates are incongruous, many predicates being frequently sup- posed to bo incongruous which are not really sO) and vice-versa. Now, much of so-called reasoning is nothing more than an attempt to show the congruity or incongruity of predicates. Suppose, for example, we take the proposition, " The sensualist, being enslaved by his appetites, cannot be free." When placed before our minds in this form there appears no difficulty in seeing immediately that " slavery to I appetites" and " freedom " are incongruous, and can- I not be predicated of the same individual. Logicians, however, must express it in the form of a syllogism, and so they say : — '' No one is free who is enslaved by his appetites : The sensualist is enslaved by his appetites, . • . No sensualist is free." We leave it to the reader to decide which is the most intelligible form. Sometimes predicates are thought to be incon- gruous which are not really so, and the way in which ; \ f PSYCIIOLOOY OF COGNITION. 239 inner. The the previous mpossible to 3r are more isistency be- s predicates To assert igure A is a in practice idicates are [uently sup- t really sO) reasoning is e congruity ov example, ilist, being e." When )re appears " slavery to Ls, and can- Logicians, < syllogism, lites : s the most be incon- y in whicli CIIAl'. V. SECT. VI. this error can be most easily corrected is to point out an instance in which the apparently incongruous predicates are plainly seen to be consistent. It might, for example, be supposed that certain modes of conduct which are consistent with holiness cannot at the same time be inexpedient. This hasty judg- ment would at once be seen to be incorrect by point- ing out some special circumstances in which it would be highly inexpedient to do some things which, after all, were quite consistent with holiness. But logicians would think that the simple pointing out of an instance to the contrary would not be enough to correct the error, and they would probably express themselves in some such way as this : — " Some practices which the Divine Law allows are in some circuinstftuce.s inexpedient ; All such practices are in themselves consi.steut with holiness : . • . Some things in themselves consistent with holinoas arc in some circumstances inexpedient." § 173. Many other examples might be given of the manner in \N'hich erroneous classifications are corrected, and the consistency or inconsistency of attributes or predicates determined. In popular language these processes are called reasoning ; and logicians, basing much of their science upon this popular phraseology, do violence to psycliology as well as to grammar by forcing them into the form of syllogisms. But, in truth, they are nothing more than the bringing together of related facts, and the percep- tion of the relations between them. This being done, the so-called conclusion is not an unknown thing ; it is directly seen. And the preliminary process is I'ii]iut„><. \ intuition that we are to look as the ground of our 1 assertion of those other relations which are predicated I in our inferences. ' From certain relations which we know, we infer I the existence of certain relations not directly intuited. j Thus, having known that a certain relation exists ' between the objects of thouglit, A and B, and between I f PS YCIfOL OGY OF CO CXI TI OX. -43 when thoro iito. Thus, ant caution it must be in bo prac- miuo what irce of our r the first be built, lition must and belief ; ■ound, their inferences leen that in lier indivi- lem. And A sequence of likeness id degrees, edications; ;wo objects le another, en to us in md of our predicated V, we infer y intuited, tion exists id between CIIAI'. V. m:ct. vir. I iitiif (if ill- j'l ri iirr (if Ji rift Jur lit. ]* and C, we infer that a certain relation exists between A and C. In this case, the objects A and C are directly known, but ihc ri'lution is not. A an object like A. 'J'lius, we have [ Tim /(><«/.•. a|)mrently two forms of inference: we inh-r the | '/ '"' existence of a relation between two objects, b(jth of wliich are known ; and we infer the existence of the unknown term of a relation, together with its relation, to some object which we know\ § 177. A few particular illustrations will make more clear the abstract statements of the last para- gi-aph. We have before us three straight A I) c lines, A, B, C. We are able to compare A with B, and B with C, and find that A is equal to B, and B to C. We infer, without directly perceiving, that A is equal to C. The relations compared are in this cnsc , so simple, and the inference presents itself to the | mind with such force, that it is usually expressel in { mathematical works in the form of an D A ]J c , axiom, or self-evident proposition — " Things which are equal to the same thing are equal to one another." But it is none the less truly an inference, although (me regarding wliich there cannot be in the mind the slightest doubt. If, again, we take four lines, A, B, C, D, of which A is equal to B, f m m y.:\ n I '' I :t W. li M I 244 fllAI'. V. XICCT. Vll. Illustra- iion of in- ference of sercnd I'orut. Till': ELEMENTS OF THE D is (lonl>lc of A, aiifl C is double of B, wo infer without lu'sitation that C is e(|Ual to I). Here tho relatiouK b('twe(.>n A and ]), 13 and C aio known, a certain ratio of longtli, A being one-lialf of 1), and li of C. Tims A and B being equal, and the relation between A and I) being etjual to tho relation between B and C, we infer a relation of equality between D and C. This inference is expressed in the mathematical axiom, " Doubles of equals are equal." Similar remarks might bo made witli rei'erenco to the majority of the mathematieal axioms. They are inferences immediately based upon intuitions; their objeets are simple, and per- fectly free from variable conditions, and there con- sequently is not the slightest room for doubt as 10 the legitimacy of the inferences. Inferences of tliis simple kind have all the certainty of intuitions ; hut yet they are not intuitions, unless we assume some other distinction between inferences and intuitions than that which we have given. They have been called axioms, or principles of mathematical thought, but this is manifestly incorrect ; they are particular examples of inferences, so simple and unavoi(.laljle that the mind can never fail t' d? w them when occasion requires. The mind .sally reco'-niscs the respective equality of two third as a sufficient reason for the inf( two are equal to one another. § 178. We now study an example of an inference in which the existence of an unknown term of a re- lation is inferred. By a long course of investigation les or figures to a nee that the 1. psYcnoioGY OF cony IT ins. 245 J>, wo infer ). Here X\w ire known, u *of I), and I) the relation tlie relation of equality 'Xpn.'Si^ed in equals are made with lathematieal lately based )le, and pci'- 1 ihi'Yid eon- doubt as 11' nccs of this uitions; but ssiinie some d intuifioiis have been cal thought, particular iiU'ivrnMiililc thciii wh( n y reivv-nises igures to a u'e that the n inference rm of a re- ivestigation scientific men had comi; to the conclusion that all material Ujdics in the universe exert upon one another an inllueuco resulting in motion, and called the Force of Attracrtion. Illustrations of this force are seen in the falling of btnlies to the earth, the motions of the moon and planets, and many other phenomena. By means of many accurate observa- tions, the laws of force, and of the consequent motion of bodies, had been calculated ; and so precisely had this been done that astronomers could predict exactly the position of any of the planetary bodies amongst the stars at any given moment. Now, it had been observed that the positions of Jupiter and Saturn at certain times were not exactly what they ought to be ; there was a certain variation in their motions which could not bo accounted for by the attraction of any of the hnoivn heavenly bodies. This variation, therefore, was a phenomenon to be accounted for; it might be the result of a mistake in the statement of the laws of motion ; it might be the result of inaccurate observations ; or it might be the result of the attraction of some unknown body beyond the orbits of Jupiter and Saturn. The first of these possibilities could not be admitted, because the laws of motion had been tested in innumerable instances and had never before failed. The second was rejected, because the observations had been taken with the utmost precision by skilled observers and accurate instruments. The only inference, therefore, which'appeared to have a sufficient reason, was the third, that there was some hitherto unknown citAr. V. si:lt. VII. i 1 II V 246 THE ELEMENTS OF THE CHAP. V. SECT. VU. Aiiothrr illuMra- tion. body beyond Saturn uliich caused the variation. And the success of astronomers in discovering tliis body proved the accuracy of the inference. Now, liere the process of reasoning appears capable of analysis into the following elements : A great body, the sun, exerts a powerful influence over a number of smaller bodies, the planets ; these also exert a similar, but, in degree, a less influence over one another ; the result of this is that certain compli- cated relations in space exist between the sun and surrounding planets. Here we liave (1) a number of bodies, and (2) a certain regularity of their motion in space. But a new phenomenon appears ; this regularity is, in a particular case, interrupted : a cause of this interruption tliere must be, and, so far, no cause is knowii ; tlie only inference which can be drawn is, that there is some hitherto unknown cause, and that the unknown cause is similar to the causes of motion already known — the forces of the sun and planetary bodies. Thus we have liere (!) a known relation between certain known bodies and their motions, (2) a motion, or variation of motion, not related to — that is, not caused by — these known bodies, and Q^i) the inference of the other term of relation, the unknown planet, (0 account for the variation. § 179. Again, in our consciousness we are aware of two great classes of plienomena, described as voluntary activities and passive states. The former we are conscious of jjroducing by our own efi'ort ; the latter we are powerless to pro(hice or to anni- hilate. As an example of the former, we may PSYCHOLOGY OF COGNITIOX. 247 instance mnscular sensations and the sounds of our ' own voice; as an example of the hitter, sounds heard, but not produced, by ourselves, and colours which we see. Now, with reference to our voluntary activities, we are conscious of a certain forth-putting I of energy in their production ; it makes no difference whether we are aware of the different links which j connect tlie conscious effort with the result or not ; we perceive an invariable relation of sequence between (1) the conscious effort, and (2) the complex of sensations which we regard as its result. But, in the case of passive states — as, say colours — we j are conscious of sensations, but the other terra of the relation is wanting; these sensations we know that we have not produced ; we, therefore, infer the other term of the relation, a cause not ourselves the productive efiiciency of which accounts for the j sensations. Analysing this process we have (1) a ' perceived relation between A (conscious effort), and B (sensations) ; (2) a knowledge of B^ (similar sensations) ; (3) the inference of A, (an ohjective cause more or less similar to A). And, be it remembered, the A^ objective is not an aggregate of other sensa- tions collected somehow together in a group, because ' everyone of these sensations requires to be accounted for in the way that we have now indicated. Tiie objective inferred term of the relation is tlierefore unknown ; we think of it as a cause adequate to the production of the perceived etTect, and its natur<' can be learned, and only learned, im])erfectlv bv the aid of hypothesis. ciiAr. V. SIICT. VII. I' !,' 248 THE ELEMENTS OF THE i. ;■ (HAT. V. SEoT. VII. In fir red nidtioii Ix'twei'ii Hiil;iioir)i poiverx. § 180. "VVe tiike still another illustration of inference, in wliicli there is inferred to exist a certain ' relation between unknown hypothetical powers. Many years ago Count Rumford made experiments I re<2;ardin2: the connection between motion and heat.* ; He found that the friction of two bodies always produced a certain amount of heat ; and that the motion of any body, whenever it was arrested or ' hindered, resulted in heat. Hence he concluded I that heat, as it -^xists in bodies, is a form of motion. i Since his time many experiments and observations I have been made regarding the relations of motion, j heat, light, electricity, and other natural forces, and I it has been clearly established that they are all ; convertible into one another. But, by inference like i that which we have examined in the last paragraph, ; there is some objective Force or cause which has a i relation to each one of these phenomena, and the ; discovery of tlie correlation of motion, heat, light, ; &c., does not result in the inference that the one l)lienomenon is the cause of the other. Intimate relations are iierceived to exist between motion, heat, and light ; the inference is that the unknown causes of these i^lienomena, hitherto supposed different, are, I in reality identical. j The accompanying diagram illustrates the difference of views produced by the experiments referred to. Originally, a different cause, F, Cal., L, is inferred to account for each of the phenomena j * This discovery is descriljod in a p;iper published in the trans- ' actions of the lluyul Society tor 17JS. psrcriOLOGY of cogxitwx. 249 m, h, c. ;* but observation sliows certain nnnierons and intimate relations between m, h, c ; it is, consequently, inferred that F, Cal., L, are really one, as represented in the united lines of the second diagram. And thus also the rela- iions between m, h, c are inferred to depend upon the community of the Force F with reference to them all. § 181. There are many inferences which have a close relation to classification. AVe have | observed, for example, that all vertebrated animals j which fly through the air by means of true wings are i oviparous as far as we have been able to discover. These observations collected together in a proposition, are thus expressed, " Birds are oviparous." Having formuhited our observations in this proposition, and having come across a class of animals agreeing in essential particulars with the known class hinh, we infer regarding the newly-discovered class that they are oviparous. We do this, althougli we have not seen the eggs or the nest ; and a naturalist would not be satisfied with his observations of a new species of birds, until he was able to verily his '■ inference by the examination of the nest and the | habits of the bird in the rearing of its young. Now, i an analysis of this process gives us the following , elements : (1) K class of animals grouped to- 1 gether by the possession of certain characteristics, j * F, force; Cal., culoric; L, light ; ni, motion ; h, hcut; c, colour, i ciiAr. V. SECT. VII. 250 THE ELEMENTS OF THE CHAT. V. SECT. vir. ■■ 1 I ChisttijV'fi- iidii i)J' oh- jcctn of inference. this class, as far as we liave observed, having in particular a certain pretlicablo attribute, oviparous ; (2) a certain number of animals observed to possess some of the essential qualites of the preceding class ; and (3) the inference that the attribute, oviparous, may be predicated of them. § 182. The preceding illustrations of inference will enable us to advance to the discussion of some important questions regarding it. But, before doing so, Ave shall offer and explain a classification of the spheres of thought in respect to which inferences are drawn. (I). We have, in the first place, inferences regard- ing the relations of particular parts of Space and Time, and, also, regarding that which is a result of a combination of Space and Time, Motion. Space and time, we have seen, are the forms of external intuition, and motion is known to us in terms of space and time. And when the lines, figures, and other dimensions of space, time, and motion are made the subjects of inference, abstraction is made from all particular content of intuition ; the inference has reference only to the elements of the forms. (II.) Inferences are drawn, in the second place, regarding certain Forces or powers which are not known to us directly as phenomena, and which, indeed, cannot be so known. The inferences have reference to the nature, relations, and laws of these powers, as well as to their connection with the phenomena through which they manifest them- selves. PSYCHOLOGY OF COO X IT 10 X. (III.) There is u tliird class of inferences, iiaving reference to the existence and rt'hitions of Piie- nomena. Tliese ijiferences cletcrniine our belief of tlie existence of phenomena not directly known in relation to certain other phenomena which we do know. But they have not reference merely to the present time ; they extend to the occurrence of past events, in which case they depend upon historical evidence ; they reach forward also to th§ future, constituting prevision, expectation, or probability, according to their degree of certainty. Before, however, we consider these classes of inferences, we must give more minute attention to the determining reasons upon which inference rests. Section YIII. determining ground of inference. § 183. In the preceding section we analysed certain particular examples of inference for the pui-pose of gaining a general knowledge of the |)rocess. We saw that inference is a mental assertion made, without immediate knowledge, regarding some relation be- tween known objects ; or, regarding the resistance and relation to known objects, of some object or power not directly knoAvn. We have seen that, in certain cases, the same inferences are uniformly draw n by all men, whereas, in other cases, there is room for doubt and difference ; and that in all cases there is some ground upon which the inference is based. Our f'MAr V. SKCT, VI U. !' I r ' !■ 1'' i # ! i k, t T 1' ■ If, &i '; -3- CHAl'. SKCT. V V. III. AritMHS , tliiir nature. THE ELEMENTS OF THE tusk, now, is to examine into the nature of this ground. It is adraitte 1 that all inferences form a part of our conscious experience ; and the question is, What is it that determines this experience? In any given case of inference, why is it tluit wo infer so-and-so, and not otherwise ? When, for example, we see two lines, each equal to a third line, why do we infer that they are equal to one another ? When w-e see the motion of any body without us taking place, why do we infer that there is some force impelling it ? When we see any seed, in germinating, putting forth a pair of leaves instead of a single one, why do we infer that the future plant or tree will grow by the addition of annual layers of woody tissue upon the outside sur- face ? In other words, what is the Sufficient Reason of any inference which makes that inference necessary or legitimate ? § 184. The question of the preceding paragraph may be discussed with reference to the three classes of inferences described in the last section. We make inferences regarding the forms of the objects of knowledge, space, time, and motion ; the forces which operate in nature around us; and the ])henomena which present themselves, or are capable of doing so, to our senses or consciousness. In connection with the first of these classes of inference, a great deal of discussion has arisen regarding the nature of the basis upon which demonstration rests. Certain axioms — such as, " Things which are equal to the same thing are equal to one another" — are generally placed at the beginning of mathematical works, and assumed IJ PSYCHOLOGY OF COGNITION. 253 to be self-evident, nature of those axioms And we have now to consider the cnw. v. One chiss of thinkers tells us that they are a p'/or/ judgments, not founded upon ^l prim-i anythmg more simple and original than themselves. Leing self-evident, and necessary, and universal, they must be original intuitions of the mind. Lut to this opinion, as it is generally expressed, there is a priind facie objection. The axiom quoted above is (jeneral in its application ; it applies to all things, of whatever , nature they may be, which are equal to one auotlier. And we may assume it for certain, that a })r(»position of this kind is not formed until after one or more particular examj^les of it have been known. Tiiis axiom, as well as all the others, has been generalised, and the question is. What is the nature of tlie parti- cular mental acts from which it has been drawn ? Now, taking the particular axiom referred to, it is manifest that the single mental act from which it is generalised must be either an intuition or an iufer- ence. A is equal to B ; C is equal to B ; theref(jre A is equal to C. This is the particular t\)rni of tlie general axiom, and must have iweceded the general axiom in historical order. In this form the mental act appears to be an inference. A is not diracih/ seen to be equal to C, but both A and C are seen to be equal to B ; and the inference is di-awn. But it has been held that this apparent inference is originally an intuition ; that we are not able to i)rL- dicate that A is equal to C until after we have com- pared them directly together ; and that, having seen several instances in which xV and C, being each equal I'.lDjill't' III Oi '■.'/• \ i i ! ^54 THE ELEMENTS OF THE I I ! ^;' ,:i, I f'HAl'. V. t weri' ide that our element ot )iiiparisou of o true tliat ', time, and f particuhir something ist be tiius n relations o quantities h afford a and affoi'd ler inference inferences Kj ground of liown. We ption of the iThere is a HEOT. vni. certain conscious elfort exerted which is folhnvi.'d bv ciim'. \ a certain result ; an event sindlar to this result occurs, but without any effort on dur part; we infer an objective i)OW('r of which it is the result. And the ([Uestion is, upon what ^rimnd do we make this ] inference? Ji(.'fore considerin<< this (piestion, we! must, in the lirst i)lace, postulate tiiat there is ^iven ; to us in consciousness a knowledge of {lower. | 31uscular sensations are the subjective side of that A'//.w-7,,/,/ of which muscuhir effort is the objc'ctive. And i„tnitin'. muscular power is U(jt known to us as a nlntion \ between muscular sensations and some ronlt. | Neither is power known to ns as a relation between | aiuj mental events and their consequents. Simple I succession can never give us the idea of j)ower. j liut in the consciousness of muscular sensation, the j (jbjective side of which is muscular effort, W(3 have a ; I' 1 direct knowledge of power; and when the organism j is in a healthy state, we are able, bv means of other I sensations, to know the results of the forth-putting \ of this p(jwer. Thus our knowledge of causal j efficiency is intuitive, although it no doubt takes ' a little time and experience to connect muscular ' efforts with their proper results. § 189. Having now got the two terms of the first An<(i>/s;s„f relation, conscious eff(jrt and its result, another object, a passive sensation, comes before conscious- ness. We know that it is not caused by us, because we have been conscious of no foith-putting of effort in its production. But why do we seek for its cause at all? Some people would answer that it is s 2 ilih V< ntiill i ,: . '• 'i 260 rriE ELEMENTS OF THE hi 1!,/ Ilii ll§ H(i (, ! <\< W I mi ii Sli''|i 'ill i (MAP. V. .SECT. VIII. AC -Ol5, because we know a iwioyi tliat every event must have a canse. Perhaps this statement may i)o resolved into tlie simple fact that we are reasoning animals, tliat by our birtli as human beings we inherit a tendencv to seareli after tlie reflations of tliinfrs, and that bv the same birthrii^dit we are never satisfied until we have discovered the relations aiid the causes of the things we know. If this is a correct interpretation of the law, we admit its truth. >so\v comes the final question — what is the ground of (jiir inference that the known passive sensation is caused o A, by an unknown objective power ? The relation between A and V> is known . B, is similar to B, in as far as it is an object of consciousness ; the inference of a subjective cause is excluded l)y the conditions of the case ; the only possible inference, therefore, is that of an objective cause, A^ holding the same relation to B, which A holds to B. It must be admittepi ritual power into every object of nature. Ho I i PSYCHOLOGY OF COGXITIOX. 2C1 § 190. The inference of some objectivo power ihv t)i<^ events wliicli we ourselves do not ])i'(xhK'e is comfuhory ; but there is great room for doubt and (iir[i;renc(> as to the nature of tliat power. J\[cn primawly inferred the existence of innumerable spirits; others have postulated a common substratum, matter^^>others infer a universal mind ; others, again, eoncljiide that tliere are various powers mutually eorrehded, wjiich are but forms of a universal J'oree. As tli^is not a work upon metaphysics, we do not feel called upon to discuss these conliietinir tlieories. Eut we may point out tiuit inferences regarding the nature and laws of the uidvuown cause or causes of phenomena must, from the nature of the ease, be hypothetical. And the best that we can do is (o adopt tliat hypothesis whi(di, to our minds, most I'ully exjtlains the phenomena. It is, therefore, U[ion a careful study of phenomena and their juutual rela- tions tliat we should build our hypothetical inferences, taking care that no phenomena be overlooki;d or placed out of tlieir proper relations. It would talce us far beyond our limits to discuss this siibject as it should be discussed. Some have held thut, because in these matters the absolute cei'tainty of mathe- matical demonstration or of intuition is unattainalde, they ought to be excluded from the sphere of science altogether. This, however, would be an arbitrary limitation of the sphere of scien(;e, against wliich the actual pra(.'ticfi of scientitic men is a standing protest. Hifpotheses jinfjo^ iNewton to the contrary notwith- standing, ift the pra(.'tical language of the man of OHM . V. sE( r. VII! ////;.- thrt. -,1 / inlti:.. "/ llljfll' ,/ dlH.i-t'i i: ' ' '■ i mm* y. ^1 % u T|lf!l 1i 3B ,: : ' , 1 , : ' ! i si ! 262 CIIAl'. V. PKt.T. VIII. In/erencps as fo cyintf-nce and rein- finii» of VtOIII. THE ELEMENTS OF THE science, oven in cases when tliere appears to be no hope of liis hypotlieses ever being directly verified. § 191. We now come to the consideration of infer- ences regarding tlie existence and rohiti(jns of plienomenal objects. Ilhistrations of tliese inferences have ah-eady been given in § 181. . . . ^Ye liav( seen, also, that they may be generally divided into two classes, in the first of which w>» inter some rehition to exist between phenomena whicli we know ; and in the second we infer the existence of a phenomenon not directly known, and holding a certain relation to another ph'^-nomenon, or set of phenomena, known to exist. And the question t^ i- decided is, what is the ground of the inferences we draw in each of these cases? Now, it must be observed that, in drawing these inferences, there is o-reat room for error. Thousands of instances mii,dit be pointed out in which false relations have been supposed to exist between phenomena. It must br admitted, then, that inferences may be drawn which are not in conformitv with the truth of nature. AntentHL» of a i holding a •n, or set of uestion t" i- nferenees we it must be ices, there is ances mii,dit have been It must br awn wliieh nre. And, nd of infer- t inference, ihenomena ich may be are not tlie IS they are that night 3r from this tion exists erroneous, as tliero are various reasons for our eoneluding tliat this is not the true relation. In drawing inferences, therefore, it is necessary to distinguish between those relations of thino-s which are acci- dental and those which are essential. \\\ order to do tliis i»roperly, we must have recourse to those laws of induction which Bacon and his followers have for- mulated. The object of these laws is to enable us to distinguish between accidentdl and essential co-exist- ences and sequences. Those relatie)ns which are of the latter class are thought to have some connection with the cause of the phenomena. And those in- ferences are thought to bo correct which connect together phenomena between which ther(; is ob- jectively a causal relation, or a relation depending upon identity of causation. The relation, for examjile, between the lowering of the temperature of the atmosphere and the deposition of dew is an esseatial one, and the inference which connected the one with the other was eorrect, although, perhaps, it is not jjroper to call this the causal relation. It is correct, also, to infer tiiat jiiiimals wdiich v,e have discovered to have some of th<' essential characteristics of birds are oviparous, because we have learned that there is an essential objective connection betwc '^ these characteristics and that 'quality which we infer. Thus, it appears that, before we can be satistied with inferences regarding phenomena, the suljfM'tive connection which we form must be recognised as being the counterpart of essential objective rela- tions between things. Inferences are not concerned ciiAr. V. se<:t. VIII. Wmu 264 THE ELEMENTS OF THE is t- ^ tf ri CHAP. V. SECT. IX. Confro- rersi/ re- tldnllwjthc ^ijUixfism. merely with the rehitions of ideas, but also, and jorincipally, with the objective connections of real tl uniijs. Section IX. THE F0R3I OF INFERENCE. § 192. Is there any general form according to which the mind acts in the drawing of inferences, and, if so, what is that form ? This question has given rise to a good deal of controversy, especially with reference to the claims of the syllogism to be considered the universal type of reaso^ 'iig. It has been asserted, on the one hand, that, if all the mental acts and principles which are involved in the drawing of inferences be explicitly stated in lan- guage, the statement will assume the form of a syllogism. It has been held, on the other, that there are many instances of reasoning in which the mental process cannot, without the greatest violence, be put into the form of a syllogism, although it is admitted that many kinds of reasoning do naturally assume that form. Before discussing this question, we must examine the nature of the syllogism. According to the accounts of the syllogism which we find in logical treatises, syllogism is inference A\hich is drawn from the general, from some proposition or judgment which is generally true. There are three terms in every syllogism, two of which, the minor and major terms, are the subject and predicate r>f the conclusion; while the third, the middle term, is PSYCnOLOGY OF COGNITION. 26s en A I'. V. t>ECT. IX. found in each of the premises, and the niediam by \vhiv.-h the terms of the conclusion are compared , together. All these terms are held to be the names of concepts having a greater or less denotation and connotation. And in the syllogism there is a com- parison of the denotation or the connotation of the j minor or major terms, with the denotation or con- ; notation of the middle term. This comparison has for its object to determine whether the one term contains the other, either wholly or partially — that is, wliether the denotation or the connotation of the one term includes, wholly or partially, that of the other. Kow, in order to determine the character j of the claims of the syllogism to be considered the j only type of reasoning, we shall have to consider, (1) whether inference proceeds only from the general, (2) whether concepts are the sole elements | of inference, and (3) whether the relation of con- j taining and contained is the only relation regarding ! which we infer. | § 193. The first of these points has been practically inferences decided by us already. We have seen that some of "."'^ ^^ the so-called mathematical axioms are generalised ' from par- ' . iiculurs. from particulars, and, consequently, tliat particular inferences are drawn before the generalised axioms are formed. We have seen, also, that in perception an objective cause of our passive states is inferred to exist from the consciousness of some particular sensation uncaused by our conscious tflfort. Now, the only ground upon which inferences of this kind can be expressed in the form of a syllogism is, tliat Jl^ \^^ \ * 266 THE ELEMENTS OF THE '! ?r>i CHAP. V. SECT. IX. \A 'ii t Inference does Wit regard con- repts hut objects. I there is an a priori principle latent in the miiul which serves for the niajor premise of the syllogism. Against this theory we have already adduced ob- jections."^ And the overthrow of this theory renders it impossible to put into syllogistic form the in- ferences referred to. There are, then, particular kinds of inference which do not proceed from general judgments, but from particular objects of knowledge. § 194. With reference to the second point, it is maintained by some that inference has to do primarily with concepts and the relation of concepts. But, as individual objects undoubtedly form subjects of reasoning, concepts are taken to be not merely the representation of the qualities of a class, but also of an individual. To this doctrine, that reason- ing refers exclusively, or even principally, to mental representations, we must take exception. Every mental representation which we make, either of an individual object or of a class, has significance to us only as related to the real objects of which it is a concept. When we make use of the term mmi^ we mean, not our mental representation of human at- tributes, but the real external objects possessing human qualities which we denote by that name. And when w^ say man is mortal, we mean that the real bei'igs whom we call men will all die. Tims, if we are to depend upon what consciousness reveals to us, inference has reference primarily, not to concepts, but to the real objects or classes of which the ♦ § 184. fi'. FSTcnoLoar of coamTioy. 267 CHAl'. V, sEr-r. IX. 1)1 ni- f'treiire. concepts are a more or less complete representation. And the predication of the inference asserts or denies a certain rehition to exist between these objects. ; § 195. What is this rehxtion ? Is it only that of liehthm the container and the contained, the mutual inclusion ^^'^^' "" ^''' or exclusion, in >vhole or in part, of two objects of thought ? A reference to particular cases of in- ference will soon decide the question. From a comparison of certain angles and triangles we infer \ — " The angles at the base of an isosceles triangle j are equal to one another." This is certainly not a ' relation of inclusion, either total or partial. From a ! variety of considerations, we infer that the rapid cooling* of the atmosphere is the cause of tlie deposi- tion of dew. It would be difBcult to put this inference into the stereotyped form. From many experiences we infer, when we see smoke, that com- bustion is going on somewhere near at hand. Tiie relation expressed in this inference is certainly not one of inclusion. In short, since inferences consist of predications, and since predications assert anij of the relations which may be perceived in intuition as existing between two objects of tliought, it is manifest that reasoning must occupy itself with all these relations. This the syllogism, in its present form, does not do; and hence, in its present form, we maintain that it is the type of only an accidental, although important, variety of the reasoning process. ^^f^Zm^ S 196. Havinc; deci(^led against the claims of the o/nnmn- syllogism to be the universal form of reasoning, we pmed. \U M I 'jm'i .1 *■ 1 ( ' >Ji m^A k 268 CHAP. V, SECT. X. 77//'; ELEMENTS OF THE might inquire if tliere is any otlier form whicli can • legitimately make .similar claims. But we shall be better able to consider this question after we have ; studied more iuUy different reasoning processes with which we are familiar. We have already divided the sphere of inference into the subordinate sphere concerned about (1) space and time, with their ' various divisions and combinations, (2) the non- phenomenal causes of things sensible, and (8) the existence and relations of phenomena. But in these : different spheres the grounds upon which the infer- i ences rest may vary greatly in their nature and ' extent, and the inferences themselves may have every variety of probability attached to them. Upon the principle of advancing from the more concrete and particular to the more abstract and general varieties of inference, the following appears ; to be a suitable division: (1) Inferences regarding ! the occurrence of particular events, depending upon evidence or testimony ; (2) Inferences founded upon analogy and induction, either particular or expressed in a less or more certain general law ; (3) Deductive inferences from general principles. Section X. EVIDENCE ; INDUCTION ; DEDUCTION. § 197. It is frequently necessary, in the common aflfairs of life, to form opinions regarding the occur- rence or non-occurrence of events, or the nature of )J PSYCHOLOGY OF COGXITION. 269 alleged facts which have not come under our own observation. These opinions are of the nature of inference depending upon what is called I'Aidence. We may divide the fncts or events regarding which evidence is taken into two general classes: (1) con- temporary facts or events, alleged to exist or occur in our own time, witldn the memory of persons now living ; and (2) historical facts or events alleged to exist or occur in some past generation. 1'ho evi- dence on whicli inferences regarding the first of these classes of faett are based is most frequently human testimony, although, in the absence of that, or when it is not thought completely trustworthy, a great variety of circumstantial evidence may be resorted to. Inferences regarding historical facts or events depend upon tradition, historical records, the existence of commemorative monuments and other things. We shall refer to certain principles by which we are guided in drawing inferences in each of these cases. § IIJS. The most direct evidence of contemporary occurrences which we have not ourselves observed is the testimony of others. But in receiving the testi- mony of others there are various things which must be considered before placing implicit reliance upon it. AVe have found by experience that some pers(jns are not truthful in relating what they have seen or heard ; that some persons are incapable of accurate observation, mixing up their own fancies or pre- judices with the facts which tlieyare observing; that some persons are very liable to be governed by cnxr. V. llcfjardinrj rary facts. Testimony. iH^ \:-H .', li .i : '■(( i 270 THE ELEMENTS OF THE cnAr. V. 8ECT. X. Cinmm- xfanti((l evitlence. Value of vvidence. interested motives so as deliberately to misrepresent in their own favour the facts wliicli they relate. These and other considerations have led to the establishment of various le^al customs connected with the takinf^ of evidence, such as the imposition of an oath, cross-questioninj^, and otliers. For the purpose of correcting human testimony it is found, also, that a variety of circumstantial evidence is of very great importance. The majority of the alleged occurrences regarding which inferences are to be drawn leave some permanent marks or traces behind them which may be afterwards observed ; and these, in the hands of a skilful interpreter, frequently form the basis of important and true conclusions. There is, however, great difference in the skill of different persons in discovering the significance of permanent marks or signs. The barbarous tribes of an unculti- vated country usually show remarkable acuteness in reading the meaning of the traces of i)ast events ; while the natural or acquired skill of the professional detective is often equally wonderful.* § 199. In determining the value of evidence, there are, generally speaking, two things to be considered ; the nature of the evidence itself, and especially the character of the persons by whom it is given, and the nature of the fact testified to. The mind fre- quently refuses assent to alleged facts in consequence of the improbability of these facts occurring. When * For a spocimen of this o^ iiieuoss and skill tlie reader is referred to Edgar A. Poc's remarkable descriptiou ' The Murder in the line Morgue.' PSYCHOLOGY OF COGNITIOX. 271 JKisidoil til rertire nr a person is well acquainted with a particular class of chai-. v. i'aots, lie knows pretty accurately wlint phenomena of that kind are likely, in ^iven circumstances, to occur, and he refuses to ac^cept the testimony of ignorant observers if their testimony contradicts his expectations. The antecedent probability or impro- bability of particular occurrences taking [)lace exerts a great influence upon our estimate of the value of! '/;/''''"''' the evidence udducetl in their favour. This predis- position to believe, or to disbelieve, alleged occur- rences varies greatly in different minds, and depends greatly upon the kinds of experience with which the mind has been familiar. If, for example, an expert in physical science is informed of the occurrence of (;ertain phenomena, such as table-rapping and other things said to be performed by spiiitual agents, he I feels a strong predisposition to attribute the pheno- 1 mena either to deliberate deception on the part of i some one concerned, or to the operation of some of the | natural forces with which he has already become ' acquainted. This predisposition, although a valuable 1 safeguard against indiscriminate credulity, often I pi'oves a hindrance to the discovery of truth by | preventing competent men from undertaking a care- i ful examination of the evidence upon which alleged • occurrenct.'s rest. With reference to every humun being it mav be said, "There are more thin^^s in heaven and earth than are dreamt of in your philo- sophy," Jind, consequently, in the mind of every human being there is likely to be a predisposition to reject the evidence of some things which are actual I v true. ' in . IMAGE EVALUATION TEST TARGET (MT-3) A <" c^ / 1 <' .. ^ "^ ^ 1.0 I.I 1.25 le, 1112 ■4tf. 112.2 1 2.0 1.8 14 ill 1.6 V]

. s'^ .. #3 6^ w i i 2/2 THE ELEMENTS OF THE CHAP. V. HECT. X. lieaardhig historic erents § 200. We now proceed to the eoiisi'loration of ; the nature oi' the evidence upon wliich inferences ['flf ■ regarding tlie occurrence of historical events are based. And it is manifest that, as a rule, tliis evi- dence cannot be so satisfactory as that of cont'Mnpo- rary occurrences. The witnesses of historical events are dead ; they cannot be put upon their oath ; they cannot be cross-questioned; the whole of thatsearcli- ing process of eliciting from unwilling, or stupid, or inconsistent witnesses the true «tate of th(3 case, with which we are familiar in modern courts of law, must I be foregone, or, at best, very imjierfectly performed. The evidence upon wliich our inferences are built consists chiefly of written documents containing j either descriptions of, or allusions to, the events concerning which we are inquiring. The account^; I of these written documents may be confirmed or ' modified bv the discoverv of monumental fi^iures or inscriptions, or other remains, and by the perpetua- j tion amongst the people of traditions or customs I apparently depending upon the alleged events. In examining the written documents, the most important points which should be ascertained are, the persons ' by whom these documents were first written ; the time when they wrote, and the opportunities which they enjoyed of becoming accurately acquainted I with the events which thev describe ; the cha- I . . .*■ I racterof the writers for intelligence and truthfulness, and especially the feelings by which they might be influenced in writing their accounts. These points having been determined, either with certaintv or PSYCHOLOGY OF COGXITIOX. 273 oration of inferences jvents are , this evi- contt'n'i]>o- ieal evc-nts latli ; thev liatseareli- stnpid. or case, witli law, must performed. are biiilt pontaiiiinu- lie events 3 aceouiitN jfirmed or figures or perpetua- r customs rents. In important le persons itten ; the ties which cquainted the cha- ith fulness, might be 386 points rtaintv or CHAP. V. HKCT. X. with a greater or less degree of probability, there will remain to subject the documents themselves to a criticism something analogous to the cross-ques- tioning of legal courts. This criticism will have for its object the obtaining of a true and complete view of the occurrences described, by bringing together disjointed accounts, harmonising, where possible, apparent inconsistencies or incongruities, and, in short, bringing into a consistent unity the great variety of unsystematically arranged details of events, and character, and life which the docu- ments present ; but it may possibly result in the conclusion that such a unity is unattainable. Ex- amples of this historical criticism are to be found in modern inquirers regarding the lives and labours of Homer, and Plato, and other ancient worthies, and especially in the modern criticism of the Christian Scriptures. § 201. As, in the treatment of the evidence adduced PiTjudice^, in favour of the occurrence of contemporary alleged l',.Ztr'i "^ events, people are under the influence of a predispo- sition to believe or disbelieve, according to the view which they are likely to take of the probability of the events occurring, so there is a similar predispo^i- tion with reference to historical events. From our own experience and from the recorded experience of others, we form opinions as to what may reasonably be expected to take place in particular circumstances, and these opinions influence our minds very strongly in our treatment of historical evidence. These pre- formed opinions, or prejudices, as they are called, it T iili ill ' "f ; ,, 1 :?74 THE ELEMENTS OF THE (HAP V. SKCT. \. lllustra- fioii 'ij' jirc- ilisjiii^ilioii Idilishdift'. is impossible to get rid of, simply because it is impossible to annihilate our own past mental history and the influence whicli it has had in forming our present character. But it is possible for us to understand that our ])rejudices may prevent us from attainin2: to a knowlednje of the truth concerniiiij: which we inquire, and it is possible for us so far to overcome our prejudices as to admit, in particular cases, that what api)ears antecedently improbable to us may nevertheless be true-. The antecedent im- probability, therefore, of any event which is not merely, ridiculous and absurd, should not prevent anyone from carefully examining the evidence upon which it rests. § 202. Perhaps the most remarkable example of the influence of a predisposition to disbelief in modern times is seen in the objections which are urged against the alleged miraculous occurrences of the Christian Scriptures, and especially against thi' resurrection of Christ. Since the revival of intellec- tual activity in the time of Bacon and Descartes, tlie attention of scientific men has been directed chiefly to the study of phenomena and to the discovery of the laws by which })henomena are usually regulated. And amongst phenomena, those which are farthest removed from mental or spiritual relations have engrossed the largest share of attention. In the scicitific mind of modern times there has arisen, therefore, through the influence of a long-continued and exclusive study of phenomena, a predisposition to doubt the occurrence of events which are plainly PSYCHOLOGY OF COGNITION. Vi beyoud the sphere of plieuonional laws, auut those whose minds liave '•■ not been vitiated by the prevailing phenomenalism j are willing: to admit the evidence of events alleged i to be produced by the power of God for a great and wortliy end. And especially whe>i they consider that these events form part of a loug-continued i I and wonderful religious history ; that they are j alleged to have occurred at a critical i)eriod of tlie i world's life, when the old state of things, politically, | morally, socially, and religiously, gave i)lace to a i uew ; that they harmonise with the character and j tlie professed aim of the person by whom tliey are said to have been performed ; and that they appear to be designed as an exhibition of the power and the gracious purposes of God with reference to the human race — when thev consider these and otlicr tilings, the antecedent improbability of tlie occurrence of the allegeil events vanishes from their minds, and they are prepared to give favourable attention to tlie historical evidence which is adduced. § 203. We now proceed to the consideration of those inferences which are drawn from particular facts or relations, and which ai'o usually called inductive. One of the commonest forms of this is analogy. Two objects agree in certain iiuiticulars, and it is inferred or expectid that they will agree in others. A child sees a tin rattle, and hears the rattling noise which, it makes when shaken. A\'hen he sees something afterwards at all resembling the I T 2 'IIAI'. V. •SliCT. A. Au.ih,( I'l. \' I i u > Is I 1,': mm 276 TI/i: ELEMENTS OF THE '' CHAV. V. sK(rr, X. Auahgy of acciihutul jeetivu force, except as an inference to account for otherwise unaccountable plienomena, so we know nothinnr about the laws of forces, exce[)t as infernal from the relations of observed phenomena. IJut the inference is one which cannot be avoided, simply because there is no foundation for any other inference. And since the particuhir inference is an unavoidable one, the induced principle is seen, without doubt, to bo of universal application. § 2<)8. Thus we see that all general laws are the result of induction, as well as those j^eneral proposi- tions which express the characteristics of classes of objects. But there are inductions and inductions. Some inductions — as those regarding the relations of mathematical magnitudes, and the laws of forces — are founded upon particular inferences, these inferences being unavoidable in the present condition of things. Other inductions are founded upon the perceived re- lations of certain qualities which we have determined, by observation and comparison, to be essential to the constitution of particular classes. Thus, in all cases of induction there must be recognised the existence of a certain established objective order of things, and our inductions are only an expression in language of what wo believe to be essential relations of this ob- jective order. If our inductions accurately correspond to the objective order, we say that they are true ; if not, not. § 209. We are now brought to the study of the last < IIAl'. V. sr.cT. X. 1:1 11(1 It iij iiidnctiim. It Dcducticn, 282 THE KLEMKXTS OF THE «:t 1 ( IIAI'. V. SECT. X. Ctrhnntij I >f infer- ence liepemh upon major j)rcimse. () form of inforonoc— the (hxlnctivo. Iloro tlic luind l)aHso.s in reasoninj^ from tho gcuurul or uiiivorsal t tho jmrticuliir. Having already known sonictliini; to bo triKj of a whole class of tilings, wo aro aMo to allirm it to bo trno of every individual of thii elass. Familiar illustrati(^ns of tho deductive process are scon in the application of tho general laws of natural forces to particular cases, and in inferences regarding the qualities of particular individuals of a class I'roni our knowledge of tho essential constituents of the class. The astronomer, having determined the laws of the motion of some particular planet, is able to infer with precision the particular point in tho heavens whicli it will occupy at any particular moment. The chemist, having determined tho laws of the com- bination of particular elements, is able to predict the result in any special case. The naturalist, having discovered tho universal characteristics of some species of animals or plants, expects with certainty to find these characteristics in every new specimen. The natural form in which inference of this kind is thrown is, no doubt, the syllogism. And the princi- pal value of the syllogism is to state, in an explicit, methodical form, those deductive inferences at which the mind arrives, frequently without any conscious reference to the major premise at all. § 210. In order that the deductive inference may be thoroughly trustworthy, the major premise must be an expression of some essential objective order or law of things. If, for example, the major premise of a syllo- gism be " All swans are white," an inference from psycnoLOfrY of couyrrios. 2^}, tliut, with rclbrcnco to the colour of any particular swans hitherto unseen, eouhl not he niado with per- I'eot eertaintv. We could never feel certain buttiait hirds nuiiht be found possessintj: "H the ess«'ntial characteristics of swans, but which were of some other colour. Whereas, if we have for our major premise, "All cows rununate," the inference with rcfeienco to particular animals of the species is cc^rtain, because tlu' predication 'of the major premise expresses an essential condition of the class. J )e(luetive inferences which luivo for their object some accidental quality or state of thinf^s can never amount to more tlinu a probability. The probability of the inference is tin* consefpience of the want of certainty which charac- terises the major premise. And that want of certainty arises either from the accidental nature of the relation which is predicated in the premise, or from our partial ignorance regarding it. ^Section XI. CONCLUSION. § 211. By way of summing up the conclusions at which wc have arrived in the preceding se(!tions, we may first point out the different kinds of inferences which we draw. One of the most important of these is the Hyiiothetical Inference* by the object of which we account for the existence of known phenomena. The existence of any particular sensation is accounted * This, of course, is altogether different from the hypothetical form of the ayllogism. 1 1 I ii,\r. V. >K( T. XI. Hi/pa- th'itlml Inj'i rtnce. 284 THE ELEMENTS OF THE CHAP. V. SECT. XI. Particular inference. for by iiiferring some objective hypothetical power. The existence of a foot-print upon the sand is ac- counted for by the supposition that a man walked along the sand some time previous. The statements of a liistorical writer are accounted for by the in- ference that the events which he describes actually occurred. Any particular phenomenon or complex series of phenomena being given, we account for its existence and character by inferring liypothetically some antecedent cause sufficient to account for it. In many cases, we may never be able to verify the inference by direct knowledge ; but it matters not ; the inference must be made, nevertheless, to satisfy that insatiable craving after a knowledge of the causes of things which is our birthright as rational beings. In inany other cases, the hypothetical inference may be verified, as in the discovery of the planet Neptune, and in the discovery of certain new metals wliich had been inferred to account for peculiar phenomena in the spectroscope. In cases where the hypothetical inference cannot be verified by direct observation, various degrees of probability, or even a practical certainty, may be obtained by considering the degree of completeness with which the particular inference accounts for the phenomena, and the absence of a foundation for any other inference. § 212. The Particular Inference founded upon siibjective association is very familiar. Two or more objects of knowledge having occurred together a few or several times, there is formed an expectation that, where one of them appears, the others may be looked PSYCHOLOGY OF COGNITION. for. The occurrence of these objects together leads the mind to suppose that tliere is some objective connection between them, and this supposition forms the ground of the inference. When this supposition is converted into actual knowledge, and the con- nection between the two associated phenomena is ascertained, the inference is no longer problematical, but acquires the character of a certainty. The Par- ticular Inference founded upon a comjMrison of sim])le Intuitions is also characterised by certainty from the verv first. When we infer that the lines A and B, being each equal to C, are equal to one another, there is no other inference which we could possibly draw. § 213. The Inductive Inference, founded upon uni- formitij of experience, never amounts to more than a high degree of probability. But it is not, therefore, to be despised, because in many cases nothing but a certain degree of probability is attainable. And in the practical concerns of life probability is our usual guide. Tlie Inductive Inference, founded upon a hioidedge of the essential relations of the things concerned, par- takes of the same amount of certainty as the knowledge on which it is founded. Illustrations of this are seen in the axioms of mathematics and of natural forces, and in the inductive generalisations regarding natural orders and species. The Deductive Inference is based upon some general principle, and rests for its conformity to trutli upon the assumed truth of the principle from which it 285 CHAP. V. SECT. XI. Inductive inftrence. Deductive inference. :.is 286 THE ELEMENTS OF THE CHAP, V. SECT. XI. Conclu- sion, Starts. The general propositions in which the dif- ferent species of induction terminate are the starting-point from which deduction proceeds in reverse order. § 214. With reference to the form in which inferences should be expressed, it appears to be a matter of very little consequence. All knowledge may be resolved into the knowledge of objects and their relations, and all inferences are concerned about the existence and relations of objects, or the occurrence of events, not directly known, and about the relations of known objects. Every inference referring to an object or a relation not directly known must be founded upon some relation which is known either by intuition or some preceding in- ference. And, in the arrangement of the different elements of the reasoning process, the grand re- quisite is that the mind should be able to pass readily, and without hesitation, from the ground to the inference. To secure this requisite is sometimes very difficult, in consequence of the obscurity or com- plexity of tlie subject with which we may be dealing. And we need not expect to get much assistance from the formula? of the logician. Difficulties in thinking are not to be overcome by any formal rules which may be laid down, but by careful and per- severing attention to the subject, and sometimes by a natural genius with which some people aio peculiarly endowed. Consistency and truth are the two things which we should strive after in our thouiihts. The former has reference to the mutual iNH ■■ PSYCHOLOGY OF COGNITIOX. 287 relations of the differeut elements of our knowledge or belief; the latter to the conformity of our thoughts with the essential order ot things. For the satisfaction of that rational nature, the pheno- mena of which we have been studying, there is demanded not merely an elaborate and consistent system of doctrine, which may, after all, be a mere airy castle, but also, and especially, a certain con- fidence that what we think is a counterpart and expression of that which is. CHAP. V. SECT, XI. LONDON: I-RINTEO DY WIM.IAM .•UAVK.c ANH SONS .STAMKlSD STniTT ANU CHAKISG CKOSS. 1 1 1 11 M H 1 ■ 1 m 1 m Bedford Street, Covent Garden, London September 1 8 74. Macmillan d. 1864.— PROBLEMS AND RIDERS. By Walton and Wil- kinson. Svo. cloth. loj. 6d. These volumes will be found of great value to Teachers and Students as indicating the style and range of mathematical study in tht University of Cambridge. Cheyne. — Works by C. H. IT. CllEYNE, M.A., F.R.A.S.:— AN ELEMENTARY TREATISE ON THE PLANETARY THEORY. With a Collection of Problems. Second Edition. Crown 8vo, cloth. 6s. dd. Svo. and and MATHEMATICS. 'rofessor of Cheyne. — continued. THE EARTH'S MOTION OF ROTATION. Crown 8vo. y. 6d. Childe.— THE SINGULAR PROPERTIES OF THE ELLIP- SOID AND ASSOCIATED SURFACES OF THE Nth DEGREE. By the Rev, G. F. Childe, M.A., Author of '' Ray Surfaces," " Related Caustics," &c. 8vo. loj. 6ii. 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Wallace has good claims to he considered as an independent originator of the theory of natural selection. Dr. Hooker, in his address to the British Association, spoke thus of the author : "O/" Mr. IVallace and his many contributions to philosophical biology it is not easy to speak without enthusiasm ; for, putting aside their great merits, he, throughout his 7uritings, loilh a modesty as rare as I belic7'e it to be unconscums, forgets his oion unquestioned claim to the honour of having originated indepen- dently of Mr. Danvin, the theories 7ohich he so ably defends.^* 77ie Saturday Review says : "///j, *' has seldom fallen into our hands." THE PROGRESS OF THE TELEGRAPH. Fcap. 8vo. \s. " While a complete vie^a of the progress of the greatest of human invefitions is obtained, all its suggestions are brought^ out 7vith a rare thoughtfnlness, a genial humour, and an exceeding beauty of utterance. ' ' — Nonconformist. Wilson (Daniel.)— CALIBAN : the missing link. By Daniel Wilson, LL.D., Professor of History and English Litera- ture in University College, Toronto. 8vo, los. 6d. *' T/u- whole volume is most rich in the eloquence of thought and itnagination as well as of words. It is a choice contribution at once to science, theology. Quarterly Review. religion, and literature." — British PHYSIOLOGY, ANATOMY, ETC. l^ ountry. lEORV ys. IV ipelagu," Crown ;e Cata- iepcndent 'ooker, in i author: losophical ; pHtting , 7iiilh a s his (Tion ' indepen- defendsy ndance of reasonim a scale. R, THE IN ITS GE WaR- 'entateuch iter who Hcbreio :ator. '.R.S.E., jurgh : — Lved after as seldom Iro. IS. nf human it 7vith a beauty of NK. By ih Litera- ught and ibution at —British Winslow.— FORCE AND NATURE : ATTRACTION AND REPULSION. The Radical Principles of Energy graphically discussed in their Relations to Physical and Morphological De- velopment. By C. F. WiNSi.ow, IVI.D. 8vo. I4J-. **J)csi'n>es thou\^hffnl and consciotlious study." — Saturday Review. WurtZ A HISTORY OF CHEMICAL THEORY, from the Age of Lavoisier down to the present time. By Ad. Wurtz. Translated by Hknry Watts, F.R.S. Crown 8vo. 6s. " The discourse, as a resume oj chemical theory and research, unites singular luminousness and grasp. A fe^o judicious notes are added by the translator."— Vail Mall Gazette. " The treatment of the subject is admirable, and the translator has evidently done his duty most efficiently." — Westminster Review. WORKS IN PHYSIOLOGY, ANATOMY, AND MEDICAL WORKS GENERALLY. Allbutt (T. C.)— ON THE USE OF THE OPHTHALMO- SCOPE in Diseases of the Nervous System and of the Kidneys ; also in certain other General Disorders. By Thomas Clifford Ali-UUTT, M.A., M.D. Cantab., Physician to the I-eeds General Infirmary, Lecturer on Practical Medicine, &c. d. Alttiough the present worli contains tfie substance of a Course of Lectures, the form fias been changed, so as tfie better to adapt it as a hand- book for students. Tlieoretical vie^vs ha-i'c been almost entirely ex- cluded: and while it is impossible in a scientipc treatise to avoid the employment of tecfinical terms, it has been the author's endeavour to use no more than absolutely necessary, and to exei'cise due care in selecting only those that seem most appropriate, or which have re- ceived the sanction of general adoption. With a very fexo excep- tions the illustrations have been dra-wn expressly for this loorkfrom specimens in the Museum of tfie A'oyal College if Surgeons. Galton (D.)— an address on the general prin- ciples W^HICII should re OBSERVED IN THE CONSTRUCTION OF HOSPITALS. Delivered to the British Medical Association at Leeds, July 1869. By Douglas Galton, C.B.,F.R.S. Crown 8 vo. y. 6d. ^^An admirable exposition of those conditions of structure 7ohicfi most conduce to cleanliness, economy, and convenience." — Times. PHYSIOLOGY, ANATOMY, ETC. 31 Hood (\A^hartOn).— ON B0\K-SKTTIX0 (so cnlled), and its Relation to the Treatment of Joints Crippled hy Injury, Rheu- matism, Inflammation, etc. etc. Hy Wharton W Hoop, M.I)., M.R.C.S. Crown 8v(). 4.?. 6^/. The author for a period a(tcHth\l the London pradirc of the late Mr. Ilutton, the famous and surressfiil luuie-setter, />\' 'ohotn he 7oas initiated into the mystery of the art and praetiee. In the pre- sent 'lUorh he i^ives a brief aeeonnt of the salient features of a bone- setter'' s method of procedure in the treatment of dama\:;ed joints, of the results of that treatment, and of the class of eases in -whieh he has seen it pro7lrdi;i' on the subject of the operation of mineral ivaters, t^'athered from the author^s personal ohsen'ation^ and from (Tery other available source of information. OUR HATIIS AND WKLI.S : The Mineral Waters of the British Islands, with a List of Sea-bathing Places. Extra fcap. 8vo. pp. XV. 205. 3.f. (hL ./laudsley. — Works by ITknrv MAUnsi.KY, M.D., Professor of Medical Jurisprudence in University College, London : — BODY AND MIND: An Inquiry into their Connection and Muturd Influence, si)ecially in reference to Mental I^isorders ; being the Gulstonian Lectures for 1870. Delivered before the Royal College of Physicians. NitaI for the I'araly^cd and Kpilcptic. (Irown Svo. 8.f. 61/. Reynolds (J. R.)— A svstkm ok mkdkink. Vol. i. Kilitcd by J. KlssKl.L Kkv.noI.DS, M.D., I'".k.('.r. London. Second Kdilinn. 8vo. 25.*. " // is the liist Cyclopicdia of iiicdiiiiif of f/ii- time." — Medical Press. Part I. Gcnnal J)isiaSi-s, or Affalioiis of the Whole System. § /. — Those deteniiiiied l>y Oi^ents operiitiiii^ from 'loilhoiit, sneh as the exanthemata, malarial diseases, and their allies. § //. — Those determi)ied by eonditions exisfim^ irithiii the hody, s/teh as (j'oiit, A'he/imafism, A'iehets, ete. J\ir/ II. I.oeal Diseases, or Aff'eetions o/partieular Systems. § /. — Diseases of the Skin. A SVSTKM OKMKDICINK. Vol. 11. Second Edition. Svo. Part IT. Local Diseases (continued). § /. — Diseases of the A'erz'ous System. .1. Ceneral uVen'ons Diseases, />'. Partial Diseases oj the A^Tons System, i. Diseases of the Head. 2. Diseases of the Spinal Column. 3. Diseases of the jVer-'es. § //. — Diseases of the DiL^estine System. A. Diseases of the Stomach. A SVSTKM OF MEDICINE. Vol. III. Svo. 25^. Par! II. Local Diseases (continued). § //. Diseases of the Di^.^estive System (continued). P. Diseases of the Mouth. C. Diseases of the Pauces, Pharynx, and Gisopha^^us. D. Diseases of the In- testines. R. Diseases of the Peritoneum. P. Diseases of the Liver. G. Diseases of the Pancreas. S JIT. — Diseases of the Respiratory System. A. Diseases of the Larynx. P. Diseases oJ the I'horacic Organs. Reynolds (O.)— sewer cas, and now to keep it OUT OF houses, a Handbook on House Drainage. Py Osborne Reynolds, M.A., Professor of Engineering at Oweas College, Manchester, Fellow of Queen's College, Cambridge. Second Edition. Crown Svo. cloth. \s. 6d. " Professor Reynolds^ admirai'le patnphlet loilla thousand times over repay its cost and the reader's most attentive perusal.^' — Mechanics' Magazine. Rolleston.— THE HARVEIAN oration, 1873. By Georcje RoLLESTON, M.D., F.R.S., Linacre Professor of Anatomy and 1! 24 SCIENTIFIC CATALOGUE. rhysiology, and Fellow of Merton College, in the University of Oxford, Crown 8vo. 2s. 6ies all preliminary to the direct exposi- tion of Moral Philosophy. These are the Certainty and Dignity of Moral Seienee, its Spiritual Geoi^raphy, or relation to other main sid'Jects of human thought, and its P'ormative Principles, or some elementary truths on lohich its whole development must depend. Boole. — AN INVESTIGATION OF THOUGHT, ON WHICH ARE MATHEMATICAL THEORIES OF BABILITIES. P.y George Boole, xMathematics in the (Queen's University, Ireland, &c. 8vo. 14J. Butler (W. A.), Late Professor of Moral Philosophy in the University of Dublin : — LECTURES ON THE HISTORY OF ANCIENT PIIILO- SOPHY. Edited from the Author's MSS., with Notes, by William Hei'Wurtii Thompson, M.A., ]\Iasler of Trinity College, and Regius Professor of Greek in the University of Cambridge. New and Cheaper Edition. 8vo. CalderWOOd. — Works by the Rev. Henry Calderwood, M.A., LL.D., Professor of Moral Philosophy in the University of Edin- burgh : — PHILOSOPHY OF THE INFINITE: A Treatise on Man's Knowledge of the Infinite Being, in answer to Sir W. Hamilton and Dr. Mansel. Cheaper Edition. 8vo. yj. 6en those ic/io are not versed in such discussions." — British Quarterly Review. A HANDBOOK OK MORAL PHH.OSOPHY. Second Edition. Crown 8vo. 6s. '^^ It is, we/eel convinced, the best handbook on the subject, intellectually and morally, and does infinite credit to its author.'^ — Standard, "y:/ com/ act and useful loork, goin^ over a great deal of ground in a manner adapted t» suggest and facilitate further study. . . . His book xoill be an assistance to many students outside his oivn University of Edinburgh.'^ — Guardian. " We cannot too heartily recommend this excellent manual to all teachers luho are anxious that the faith of theii pupils should be strengthened by sound philosophy and substa-iiial logic, and that their philosophy should be enlightened by the purest of all lights— that from heaven." — John Bull. Green (J. H.)— spiritual philosophy.- Founded on the Teaching of the late Samuel Taylor Culeridoe. By tlie late Joseph Henry Green, F.R.S., D.C.L. Edited, with a Memoir of the Author's Life, by John Simon, F.R.S., Medical Officer of Her Majesty's Privy Council, and Surgeon to St. Thomas's Hospital. Two Vols. 8vo. 25J. Huxley (Professor.)— lay sermons, addresses, AND REVIEWS. See Physical Science Catalogue preceding. Jevons. — Works by W. STANLEY Jevons, M.A., Professor of Logic in Owens College, Manchester : — THE SUBSTITUTION OF SIMILARS, the True Principle of Reasoning. Derived from a Modification of Aristotle's Dictum. Fcap. 8vo. 2s. 6d. ^'■Mr. Jevons' book is very clear and intelligible, and ijttiti ivorth con- sulting. " — Guardian. MaCCOll. — THE GREEK SCEPTICS, from Pyrrho to Sextus. An Essay which obtained the Hare Prize in the year 1868. By Norman Maccoli^, B.A., Scholar of Downing College, Cam- bridge. Crown 8vo. 3J. 6d. ^'Alr. Maccoll has produced a monograph lohich merit the gratititde of all students of philosophy. His style is clear and zngorous ; he has mastered the authorities, and criticises them in a modest but independent spirit." — Pall Mall Gazette. M* Cosh. —Works by James M 'Cosh, LL.D., President of Princeton College, New Jersey, U.S. ' * He certainly shores himself skilful in that application of logic to psychology, in that inductive science of the human mind which is 26 SCIENTIFIC CA TALOG UE. M'Cosh {}.)— continued. the fine side of English philosophy. His philosophy as a whole is worthy of attention." — Revue de Deux Mondes. THE METHOD OF THE DIVINE GOVERNMENT, Physical and Moral. Tenth Edition. 8vo. \os. 6d. " This work is distinguished from other similar ones by its being based upon a thorough study of physical scieme, and an accurate kno^dedge of its present condition, and by its entering in a deeper and more unfettered manner than its predecessoi's upon the dis- cussion of the app-opriate psychohqical, ethical, aiui theological ques- tions. The author keeps aloof at once from the h. priori idealism and dreaminess of German :peculation since Schelling, and from the onesidedness and narrvivncss of the empiricism and positivism which have so pm'ailed in England." — Dr. Ulrici, in "Zeitschrift fiir Philosophic." THE INTUITIONS OF THE MIND. A New Edition. 8vo. coth. loj. 6d. "The undertaking to adjust the claims of the sensational and in- tuitional philoscpJnes, and of the hi. posteriori andk priori methods, is accomplished in this work zvith a great amount of success." — Westminster Review. *'/ value it for its large acquaintance 7oith English Philosophy, rchich has not led him to neglect the qreat German works. I admire the moderation and clearness, as well as comprehensiveness, of the author'' s vieivs." — Dr. Dorner, of Berlin. AN EXAMINATION OF MR. J. S. MILL'S PHILOSOPHY: Being a Defence of Fundamental Tiiith. Crown 8vo. yj. bd. ''^Such a work greatly needed to be done, and the author zvas the man to doit. This 7)olumc is important, not merely in reference to the views of Mr. Mill, but of the whole school of 7vr iters, past and present, British and Continental, he so ably represents." — Princeton Review. THE LAWS OF DISCURSIVE THOUGHT: Being a Text- book of Formal Logic. Crown 8vo. 5^. " The amount of summarized information which it contains is very great; and it is the only work on the very important subject with which it deals. Never luas such a work so much needed as in the present day." — London Quarterly Review. CHRISTIANITY AND POSITIVISM : A Series of Lectures to the Times on Natural Theology and Apologetics. Crown 8vo. is. 6d. MaSSOn.— RECENT BRITISH PHILOSOPHY : A Review with Criticisms ; including some Comments on Mr. Mill's Answer to Sir William Hamilton. By David Masson, M.A., Professor of Rhetoric and English Literature in the University of Edinburgh. Crown 8vo. 6j. MENTAL AND MORAL PHI LOS OP H V, ETC. 27 *' IVe can nowhei'e point to a luork which gives so clear an exposi- tion of the course of philosophical speculation in Britain duriui; the past century, or xvhich indicates so instructively the mutual in- fluences of philosophic and scientific thought. " — Fortnightly Review. Maurice. — Works by the Rev. Frederick Denison Maurice, M.A., Professor of Moral Philosophy in the University of Cam- bridge. (For other Works by the same Author, see Theological Catalogue.) SOCIAL MORALITY. Twenty-one Lectures delivered in the University of Cambridge. New and Cheaper Edition. Crown 8vo. lOJ. dd. *' Whilst reading it 7ve are charmed by the freedom from exchisiveness and prejudice, the large charity, the loftiness of thought, the eager- ness to recognize and appreciate 7uhatever there is of real ivorth extant in the world, ivhich animates it from one end to the other. We gain new thoughts and neio ways of viciving things, r<.