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 6 
 
INTKODUCTION 
 
 TO AM 
 
 ESSAY ON SCIENCE. 
 
 BY ROBERT SPEAR, 
 
 UACHEl.(iR AM) MiKNTIATK Of MKInriNF. OF-TIIR rM\^RM1V .if . «MBNI|><.(.; 
 MBMHKR OF IIIK IIOYAI. 1 OI.LIM.F OP PIIY>KIA>S, L<IM>0^. 
 
 TOUONTO: 
 
 II. & W. ROW SELL. 
 
 1844. 
 
ROW8BLL8 AND THOMPSON, PRINTERS. 
 
IN'I KODl'CTION 
 
 TO AM 
 
 KSS.VV ON SCIENCK. 
 
 Tin: history of philosophy shews, that when 
 the mind is oifted with knowlodjje, and energy in 
 its pursuit, an observation, experiment, or idea, 
 oftentimes reveals to it a further amount of 
 knowledge, of which it had not previously any, 
 or only a very va<fue, conce])tion — oftentimes 
 jrives to it the first happy glimpse of a true 
 definition, law, theory, science or method. Wo 
 have instances of this in some of the ;)oblest 
 and most useful discoveries which have been 
 made, and which at first by a mere chance were 
 seen, and afterwards speculated on, verified or 
 applied. Thus, a chance association disclosed to 
 Archimedes in his bath a method for deter- 
 mining the s])ecific gravities of bodies. Bacon 
 speaks of his Noinim Orfrauum, as originating 
 in a happy thought, and rather the product of time 
 than of genius. Thus, the endeavour of Harvey 
 to account for the use of the valves in veins. 
 
o 
 
 led him to the discovery of tlic circulation of the 
 blood. The api)le which fell on Newton aroused 
 his meditations on the subject of jrravitation. 
 A discussion on the nervous fluid, Locke tolls us, 
 gave rise to his Essay on the Human Under- 
 standing. A chance observation of Jenncr led to 
 vaccination, and of Gaivani, opened the field of 
 galvanism ; and the unforeseen result of a lucky 
 experiment, led Laennec to mediate auscultation. 
 These may be taken as examples of the usual 
 way by which gifted minds arrive at the laws 
 of things observed, and by which, in many cases, 
 they proceed from things known, to the deter- 
 mination of things previously ignored. 
 
 From which it appears, that in many cases it 
 is not in our power to separate the origin of a 
 science from its maturity ; for in the attempt so 
 to do, the science itself often vanishes, and we 
 have left merely the thought or fact, which 
 although the accidental incentive to investigation 
 or discovery, or even fundamental in the science, 
 was perhaps long before known alike to philo- 
 sophers and to the multitude. And there seems 
 iis little reason in tracing, for example, the 
 science of electricity to him who first noticed the 
 attractive and repulsive actions between amber 
 when rubbed and light bodies — whether he were 
 a aage of Greece, or some fisherman on the 
 shores of the Baltic — as there would be in tracing 
 the science of univeraal gravitation to him who 
 firat observed the curve made by a projectile. 
 
s 
 
 ho 
 
 An accumulation of particular facts in the 
 memory is one thing, and very different from a 
 knowledge of their causes hy a rigid induction : 
 the former, by itself, cannot constitute science ; 
 the other supposes the former, and also it sup- 
 poses science — for without knowledge, facts would 
 accumulate to little purpose and fruition ; and 
 knowledtje without facts would be va«jue. With 
 both conjoined, we are enabled to copy nature by 
 art, and to prove the coincidence of phenomena 
 under one or other more or less general law. 
 
 Science, then, in the true acceptation of the 
 term, requires for its rise and progress an under- 
 standing fitly trained in the investigation of U«e 
 causes of particular phenomena, and consists of 
 two parts inseparably united: (1), that which 
 relates to practice ; and, (2), that which relates 
 to theory. The practical part is not only that 
 from which the theory is derived, but also that to 
 which it tends ; as by arts and other inventions 
 a theory is made useful, and its soundness deter- 
 mined. In other words, as the theoretical part 
 arises out of the practical, so the mind must be 
 initiated into the latter, and follow and solicit 
 na+'ire therein, before it can arrive at the other. 
 And after such scholarship only, it is enabled, in 
 many cases, to find out and to set in order a truly 
 natural theory, which disclosing the secrets of 
 Nature's operations on the one hand, points out 
 on the other a more or less easy process of 
 obtaining artificially, either a close imitation or 
 
i 
 
 an original adaptation of natural contrivances. 
 And as in the world without us, there is no 
 object absolute, save God alone, but every thing 
 which is, derives somewhat from other beinjrs 
 and thinp^s with which it is surrounded : so also 
 in philosophy, each branch, thou<^li different in 
 name, is in reality of one nature and family. And 
 an adequate definition of any science must be in 
 accordance with these principles. Thus, che- 
 mistry, for example : — (1st). Its practical part is 
 to simplify compound, and to compound simple 
 bodies ; and to find out the qualities and dif- 
 ferencing marks of bodies simple and of bodies 
 compound. (2nd). Moreover, its object is to 
 determine, as' far as possible, those fundamental 
 principles or laws which regulate every variety 
 of natural separation and combination between 
 bodies, and this constitutes the theory. (3rd). Still 
 further, it receives support from other branches 
 of philosophy — as heat, light, gravity, electricity, 
 &c., and these are the sources of its strength and 
 increase. (4th), and lastly. Its application to 
 arts, as medicine, agriculture ; and to manufac- 
 tures, as to the making of sulphuric acid, steel, 
 glass, sugar, &c., constitutes its final cause or use. 
 And the like definition holds true, and may 
 be given of every other science, by merely trans- 
 posing the objects, laws, and ends of chemistry, 
 for those objects, laws, and ends peculiar to the 
 science to be defined. 
 
 Thus, the science of metaphysics : its practical 
 
5 
 
 part is the consideration of objects jihstractcd 
 from all particulars (time, ])lace, (piantity, ^:c.), 
 as — God, space, eternity, matter, mind, motion, 
 time, and the like ; its theory, the considerati(m 
 of their necessary laws. It abstracts therefore 
 its objects from all thin<^s. Its further use is to 
 enable us to conceive a law, theory, cause, &c., 
 to account for particular phenomena, which wo 
 test by observation or experiment.* 
 
 Natural sciences are derived from natural 
 philosophy, .aptly termed the mother of them 
 all ; for it comprises the qualities and quantities, 
 the motion and rest, the mechanism and uses of 
 each and of every object, natural and artificial, of 
 mind and of matter. And amid these parti- 
 culars, it is for us to trace manifestations of 
 order, principles of connexion — some design, 
 which may lead us from less to more general and 
 definitive marks and relations ; to the classifica- 
 tion of things similar, till by well-directed endea- 
 vours we are enabled to seize on those more 
 silent and unobtrusive qualities which keep them 
 in harmony as parts of a system together. And 
 it is obvious, that from a few principles derived 
 from qualities apparent or easily appreciated in 
 
 jal 
 
 * " We have assigned to metaphysics the inqinry into formal 
 and final causes. * * * That science is the worthiest which least 
 chargeth man's understanding with multiplicity, and it is evident 
 that that is metaphysics, as that which principally speculates those 
 simple forms of things, which though they he few in number, yet 
 in their eonunensurations and co-ordinations they make up all 
 kinds of variety." — Bacon Adv. of Learning. 
 
6 
 
 some objects, Nature, when closely watched, by 
 the small numl)cr of the laws which she employs 
 to produce different actions, reveals to us the 
 existence of the same qualities in other objects, 
 whether these be in most respects similar, or 
 more complicated or more removed from experi- 
 ment, or in which the qualities themselves looked 
 for are less easily traced ; oftentimes secures to 
 us the powerful assistance of analon^y, in lieu of 
 the infinite repetition of analysis, or, in cases 
 where analysis would be impossible ; opens to us 
 (after having ascertained her laws) a further and 
 satisfactory view of other objects, in which those 
 qualities inhere ; and enables us to see onward, 
 as through a glass, the relations of other things, 
 and to determine them with more or less exact- 
 ness, although individually and experimentally 
 unknown. And thus, by means of a few natural 
 principles, we are admitted to the knowledge of 
 an almost infinite variety of things : as when we 
 affirm gravitation throughout the planetary sys- 
 tem ; affinitv in all chemical combinations of 
 dissimilar bodies ; neutrality in the union of an 
 equivalent of a(nd and of base ; combustion in 
 all changes which take ])lace in the combination 
 of oxygen with (the so-called) simple bodies ; 
 a nervous system in play, wherever there is 
 muscular action in living animals. And besides 
 these discoveries, we may notice those admirable 
 endeavours of philosophers, who, being in advance 
 of the age in whicli they lived, and of direct 
 
 (iX 
 
an 
 
 les ; 
 is 
 ides 
 ible 
 
 rect 
 
 
 experiment, have endeavoured to understand or 
 to define phenomena : as the two discoveries of 
 Bacon, in his elaborate essav on the form of 
 heat. (1). The definition of latent, or combined 
 heat ; proved experimentally by Black, more 
 than a century after. ('2). That the effects of 
 time on, and the decomposition of some bodies, 
 arc the results of combustion ; and this, some 
 years before air was known to be a ponderable 
 body, and a century before oxy«ron was found out 
 in a separate state, or was ex})erimentally known 
 to play any part in combustion. Also the c(m- 
 clusion of Copernicus, that if his system were 
 true, the planet Venus would ap^Ksar at times 
 homed like the moon — a conclusion afterwards 
 verified. The conclusion of Lavoisier, from gene- 
 ral considerations, that earths are but metallic 
 oxides, irreducible by the methods employed, 
 some time before Davy reduced them by galvan- 
 ism. The well-known query of Newton, who 
 from the similarity of the action of light on 
 inflammable bodies, and on the diamond and 
 water, deemed it highly probably that com- 
 bustible elements existed in these last — after- 
 wards ascertained ex|HTinien tally by the Floren- 
 tine academicians, and by Cavendish. The very 
 hypothetical query (the germ as it were of a 
 great discovery) of Gilbert, and of Bacon after 
 him, whether a body at a certain distance from 
 the earth might not lose all attraction for it, 
 and never return — afterwards demonstrated by 
 
8 
 
 Nowton. Thus oven in physics, the f^rcatest 
 efforts of human kno\vhMl«,^e leave experiments in 
 the rear ; so nuieh are they in error who assert, 
 that tlie whole of philosophy consists in the 
 experiment. 
 
 These things establish, that man is enabled by 
 some rule, after observations made, to speculate 
 truly concerning their causes ; and this end is 
 achieved, by bringing his sj)eculations to some 
 test, besides their agreement with metcaphysical 
 truth, and with the established rules of propo- 
 sitions and demonstrations — a test which assures 
 him whether the cause assigned is remote or 
 proximate; whether it enters into the nature of 
 the thing sought, or is merely instrumental in 
 its display or change — a test, in fine, which 
 enables him to a certain extent to separate 
 those occasional causes which the nature inquired 
 after may exist without, from tbose causes which, 
 entering into that nature, proclaim, that wher- 
 ever it is, they must be. Such a rule is the fol- 
 lowing : — that Nature is true to herself in all 
 her laws ; that the same natural actions arc 
 regulated by the same intrinsic causes, through 
 all time and in every place ; that the truths of 
 science remain the same, whenever and wherever 
 the facts on which thev rest are found ; the 
 same in one country as in another, in one being 
 as in another, in the heavens as in the earth — 
 tlu^ same vfsterdav and for I'ver. With this 
 rule, we apply to Nature, not only for observa- 
 
I 
 
 1 
 
 i 
 
 lions, but also for ang^v^ers to our suppositions, 
 theories, &c., and we then assume laws when 
 her actions and our own speculations coincide. 
 
 Further, as we live in a system in which all 
 thintrs are related and mutually sustained — in 
 which no one thinjj or action exists alone and 
 independently — the law has been derived : That 
 any efficient supposes a co-efficient, and that any 
 action supposes re-action in things ;* a law which 
 from its universality contains, as it were, all 
 other less general laws, being applicable alike to 
 the demonstration of opposing forces, and to the 
 laws which regulate the combination of bodies ; 
 equally true of all things inanimate as well as 
 animate ; of the cohesion of the molecules of a 
 body, and of this, whether in motion or at rest ; of 
 the planets, reciprocally attracted in their revo- 
 lutions; of iron, with the load-stone; of an acid 
 with an alkali ; of air with a plant ; of food 
 with its so-called assimilating juices ; of con- 
 sciousness with its object. By which law we 
 discard from philosophy both the distinction 
 made by the ancients, and adopted by some 
 among the modems between active and ])assive 
 natures ; and also that perplexing and inter- 
 minable variety, set down by logitiians, of efficient 
 causes ; or reserving some of them, merely to 
 assist us in our search after the true or neces- 
 sary, that is, the proximate efficients — which, as 
 
 • Nt'wton'i Prliidpia. 
 
^ i! 
 
 10 
 
 Bacon expresses it, " give the forms or laws of 
 thinjrs, and in which the power of man resides." 
 By which law we may, for the sake of example, 
 infer the narrowness and unsoundness of the 
 more modem doctrine, which makes the relation 
 of cause and effect to be a relation — or a sort 
 of priority and sequence — between a remote 
 occasional efficient and some assigned nature, 
 popularly termed the effect ; a partial and one- 
 sided view of a synthetical arrangement of dissi- 
 milar and incongruous things : as over-feeding 
 or starvation, the cause of death ; as an object 
 of sense, the cause of pleasure or pain ; as fire, 
 or a liquid and cold acid, the cause of the 
 liquefaction of iron, or of the explosion of gun- 
 powder ; thus leaving us as much in the dark as 
 we were before of the nature of death, pleasure, 
 pain, iron, gunpowder, &c. ; whereas the true 
 causes of these things will also be found in the 
 part or organ which dies, and in the state or 
 constitution of the being pleased or pained, and 
 in the nature of the iron, which has its own 
 peculiar laws or causes, and by which alone, at ;» 
 given temperature and pressure, it liquifies, and 
 with a given acid it combines ; and gunpowder, 
 having another nature, other causes act in it, 
 by virtue of which it is decomposed, and its 
 elements explode. For in physics the inquiry 
 is into those efficients which are concealed and 
 active in the thing itself ; efficients which, when 
 discovered, disclose to us at once the nature of 
 
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 its 
 
 liry 
 
 md 
 
 hen 
 
 of 
 
 11 
 
 tliat effect, in the production and continued 
 existence of which they equally, simultaneously, 
 and of necessity participate. 
 
 It is, perhaps, not to be wondered at, that the 
 ancient, and especially the Grecian, philosophers, 
 who were such masters of the more abstract 
 sciences — logic, metaphysics, geometry — should 
 have made but little progress in physics, in the 
 practical part of which our senses are our chief 
 guides, and in which any practical difficulty 
 that can be solved, is to be solved by experi- 
 ment. In the former, the practical part is not 
 so much in the world without us, as in our own 
 minds, and among our own ideas ; the mind, 
 having already abstracted in great measure what 
 it requires from external nature, now closes the 
 eye upon it. In physical sciences, man is the 
 observer of what passes without, and he tries as 
 much as possible to separate his ideas from the 
 external objects under observation ; considering, 
 for instance, light, h(Mt and sound, as bodies or 
 finalities in contradistinction to the sensations 
 which they produce ; drawing conclusions as if 
 light were not luminous, but a subtle matter ; and 
 heat, a peculiar motion among the minute parts 
 of bodies ; and sound, as if not audible, but a 
 vibration. Men, imbued with a metaphysical 
 spirit, would — while a true method of cxpcri- 
 uienting was unknown — from the force of habit, 
 look for the same sort of evidence, and search for 
 truth in the same channels to which they had 
 
I 
 
 n 
 
 » I 
 
 U 
 
 been accustomed, and strive at once to reach the 
 most general principles ; and the cause which 
 Thales assigned for the attraction between amber 
 and light bodies — that the essence of amber was 
 by friction transfused and imparted — is charac- 
 teristic. And to the question, Is physics, as a 
 science, possible ? most Grecian philosophers 
 would, in all probability, have answered, that 
 its possibility rested on the capabilities of the 
 human mind to find out the real essences of 
 things, that without these, as Nature does not 
 and cannot perform any action, so also without a 
 knowledge of them we should be in the dark 
 respecting her operations ; that we must know 
 how she binds, before we after her can put 
 together — and how she separates, before we can 
 put asunder ; that as any demonstration requires 
 that each step thereof should be linked to one or 
 other proposition, the truth of w Inch is intuitively 
 known and thus the necessary truth of the demon- 
 stration determined ; so also it would be required 
 in physics, to know at starting those laws or 
 axioms which Nature had proposed to herself, 
 and by which she has contrived, worked, differ* 
 cnced, united, harmonized, and established all 
 things ; that it is not a vague and indeterminate 
 knowledge of the real existence of such essences, 
 as the only possible conditions of the existence of 
 things, but a direct and discriminating insight 
 into the manner of their existence and instru- 
 mentality. That in this way aloue we could 
 
 ■ 
 
 li 
 
I 
 
 13 
 
 arrive at truth in physics, and define an object 
 without us, with accuracy, as we do a complex 
 conception, or demonstrate the precise constitu- 
 tion, for instance, of a stone or of water, of the 
 brain or of bile ; or the real difference between 
 li»»litning and our culinary fires, or Ixjtween 
 venous and arterial blood ; as we demonstrate 
 the properties of a triangle, or difference a par- 
 ticular from a universal syllogism. And it in 
 all probability would not easily have occurred ta 
 thoir understandings, to leave out these essences 
 altogether ; or, at any rate, to consider them as 
 unknown quantities in their investigations ; and, 
 instead of beginning where Nature began, to take 
 the opposite plan, and to begin where she, ha\ing 
 completed, left off (if we may so speak), among 
 things the most obvious and superficial. By not 
 following this course, the ancients were at tho 
 onset thrown on unsurmountable difficulties, or 
 lost in visionary speculations : the harmony of 
 numbers, the theory of atoms, starry influences, 
 critical days, substantial forms, circular motions, 
 occult qualities, unintelligible definitions, the ele^ 
 ments of things, &c. ; and thus physics, contrary 
 to its everlasting foundations, was severed from 
 Nature, and ingeniously built-up on imaginations 
 and matters of opinion, in which man is rather 
 the interpreter of his own thoughts, than the 
 patient dissector and narrator of things, and the 
 faithful and undisguised expositor of those laws 
 
 which regulate them. 
 
^M. 
 
 14 
 
 ■I I 
 
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 ^« 
 
 i t 
 
 It is to tliis labor lost that Bacon, we prc- 
 Miino, alludes in his definitive sentence, that 
 *' tlio ancient Greeks were like children, ripe at 
 lulk, but unripe in works ;" and says he "if our 
 complaint appear unjust to any one, while so 
 gi'uat a philosopher as Aristotle, assisted by so 
 great a prince as Alexander, has compiled such 
 an exact history of animals, and while others 
 have written copious histories on plants, metals, 
 fossils, &c., he does not appear sufficiently to 
 understand our meaning. A natural history 
 compiled for its own sake is one thing, and a 
 natural history collected for informing the under- 
 standing, in order to the building up of natural 
 philosophy, is another." For by this, in the 
 main, is added to natural history all those bene- 
 fits which it is capable of conferring on mankind : 
 and as he who first described the silk-worm or 
 the cotton-plant, water, the load-stone, nitre, 
 lightning, intermittent fever, &c, unquestionably 
 did little in comparison for mankind with him 
 who to the first, added the manufacturing of silk 
 or cotton as a garment ; or to the second, the use 
 of water in the turning of wheels, and its adapta- 
 tion to mills and machinery ; or to the third, the 
 mariner's compass ; or to the fourth, gunpowder 
 and its use in the art of war, and in mining, and 
 the use of nitre as a diuretic and in inflamma- 
 tions ; or to the fifth, lightning conductors ; or 
 to the sixth, a specific, as bark, for the cure of 
 the disease : so those who wrote on natural his- 
 
 f 
 
1.J 
 
 I 
 
 tory, for its own sake, did little in r()m])jirisoii 
 with those who elevated it from a merely formal 
 existence, and brouij^ht it to action and useful- 
 ness, and bound it to natural philoso])hy by the 
 samc ties that we are bound to liealtli, enter- 
 prize and command. 
 
 This great change, which constitutes so re- 
 markable an epoch in the history of the human 
 mind, may be traced to causes and effects which 
 liad for a long while previously been in active 
 operation ; the chiefest of which, without doubt, 
 was, the spread of Christianity in Western 
 Europe — which applying another sort of evidence, 
 and deciding at once, and by a revelation, on 
 those great questions, w hich had till then engaged 
 the attention and ingenuity of philosophers of all 
 sects, and in all ages — the existence of God, the 
 nature and immortality of the soul, the purest 
 morality, the highest felicity. By answering 
 these, on an authority which is infallible, and 
 with a clearness and precision which brought 
 them home to every one, and this not only on sub- 
 jects which could be explored by human reason, 
 as the necessary existence of God, and the sure 
 immortality of the soul, thinking or unthinking ; 
 but also on those altogether out of the reach of 
 unassisted human reason : as the providence and 
 the mercy of God; the constant activity, the 
 happiness or misery of the soul through immor- 
 tality ; added to this, a morality and felicity 
 marked out for man here, in connexion with 
 
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 11 
 
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 those future prospects to be realized hereafter. 
 This spoiled metaphysics of its chief charm, as a 
 separate philosophy ; and Christianity, created 
 and enriched by revelation, took its place in the 
 minds of men : an infinite boon conferred on 
 mankind ; and, in a worldly sense, a great gain 
 to the illiterate believer, thus without previous 
 training or preparation of the understanding, 
 enlightened from above, and no loss in this life 
 to the unbeliever who preferred the darkness of 
 the old way ; but the philosopher saw, that for 
 reputation and usefulness, he must cast about for 
 new paths — that it was absurd to set up a candle 
 where men had the sun to guide them. How, 
 then, was the restless and inquisitive spirit of 
 man now to be satisfied, now that the objects 
 of its greatest concernment here and hereafter 
 to know, had received an illumination which set 
 human reasoning and question at rest for ever ? 
 Physics, indeed, in respect of its objects, was 
 evident to the senses from the creation of the 
 world, and doubtless admired. Man must, in 
 many cases, have applied it with success. In a 
 less remote antiquity it was dwelt on with delight, 
 and considered worthy the devotion of the most 
 exalted understandings. In the Egyptian tem- 
 ples, w^e are told, were placed the images even of 
 brutes, that had by their instinct afforded lessons 
 on inventions to mankind. The successful pro- 
 fessors of medicine, and of other arts, were in 
 many instances numbered among the gods. To 
 
17 
 
 sreafter. 
 rm, as a 
 created 
 e in the 
 rrcd on 
 3at gain 
 previous 
 tanding, 
 this life 
 iness of 
 that for 
 ibout for 
 a candle 
 . How, 
 spirit of 
 \ objects 
 lereafter 
 rhich set 
 or ever? 
 }cts, was 
 1 of the 
 must, in 
 s. In a 
 delight, 
 the most 
 ian tem- 
 5 even of 
 [I lessons 
 sful pro- 
 were in 
 )ds. To 
 
 Archimedes (as is well known), for his skill in 
 science, was intrusted the defence of Syracuse. 
 To Aristotle, that he might compose a natural 
 history of animals, was given jwwer over all men 
 who could assist him in G recite and Asia Minor. 
 Hence, even in ancient times, it was not for the 
 want of hope of j)hysics, as a subject of great 
 extent, and pregnant with usefulness, that men 
 remained at a stand-still or advanced singly, or 
 by chance, from first to last. It must, then, have 
 been, either because their minds were pre-occu- 
 pied by other, and still more fascinating investi- 
 gations, or for the want of a method, which, as in 
 all things, so in this chiefly, is required. 
 
 After the revival of learning in Europe, when 
 the health of the body-politic gave occasion to 
 the developement of a sound appetite for the 
 increase of knowledge, towards the close of the 
 sixteenth century, natural philosophy was pur- 
 sued with extraordinary success by Gallileo, 
 Des Cartes, Bacon, Kepler, &c. But ever and 
 anon the want of a true method became appa- 
 rent: imaginary speculations often took their 
 place, side by side, as equally true and important 
 with Nature's laws. Kepler, as if in mockery of 
 his famous discoveries, revived the antiquated 
 notion that the earth was animated, and that 
 the tides were the effects of its respiration. 
 Des Cartes sought for the cause of the blood's 
 motion in the works of Aristotle. When Bacon, 
 a severe observer of Nature, perceiving the 
 
IS 
 
 extreme insufficiency and inapplicability of the 
 logic in use, and assisted by the few discoveries 
 at his time known, and the few experiments 
 which had been turned to useful purposes, op- 
 posed himself singly to destroy the rooted conceits 
 of philosophers, which for nearly two thousand 
 years had derived support from the decisions of 
 Aristotle; and moreover published, and dedi- 
 cated to mankind, his new n.ethod. This work, 
 confessedly unfinished in its minor parts, had an 
 immediate success ; it was lauded by kings, and 
 rivetted the attention of historians and philoso- 
 phers ; its natural simplicity and truth forced 
 the logic of Aristotle to give way, and the title 
 which he had so long held, of Nature's Secretary, 
 was, bv common consent, transferred to Bacon. 
 
 I'Ab.