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researches, upon the maxim, that no organ exists without its appropriate destination; and although he may often fail in his attempts to ascertain what this destination is, he never carries his scepticism so far, as, for a moment, to doubt of the general principle. I am inclined to think, that it is in this way the most important steps in physiology have been gained; the curiosity being constantly kept alive by some new problem in the animal machine; and, at the same time, checked in its wanderings, by an irresistible conviction, that nothing is made in vain. The memorable account given by Mr. Boyle of the circumstances which led to the discovery of the circulation of the blood, is but one of the many testimonies which might be quoted in confirmation of this opinion.
"I remember that when I asked our famous Harvey, in the only "discourse I had with him (which was but a little while before he "died) what were the things which induced him to think of a cir"culation of the blood? he answered me, that when he took notice, "that the valves in the veins of so many parts of the body were "so placed, that they gave free passage to the blood towards the "heart, but opposed the passage of the venal blood the contrary 66 way, he was invited to think, that so provident a cause as nature "had not placed so many valves without design; and no design "seemed more probable, than that, since the blood could not well, "because of the interposing valves, be sent by the veins to the "limbs, it should be sent through the arteries, and return through "the veins, whose valves did not oppose its course that way."*
This perception of design and contrivance is more peculiarly impressive, when we contemplate those instances in the animal economy, in which the same effect is produced in different combinations of circumstances, by different means;-when we compare, for example, the circulation of the blood in the foetus, with that in the body of the animal after it is born. On such an occasion, how is it possible to withhold the assent from the ingenious reflection of Baxter!" Art and means are designedly multiplied, that we might
Boyle's Works, Vol. IV. p. 539. Folio ed. See Outlines of Moral Philosophy, p. 185. (Edin. 1793.)
The reasoning here ascribed to Harvey seems now so very natural and obvious, that some have been disposed to question his claim to the high rank commonly assigned to him among the improvers of science. The late Dr. William Hunter has said, that after the discovery of the valves in the veins, which Harvey learned, while in Italy, from his master Fabricius ab Aquapendente, the remaining step might easily have been made by any person of common abilities. "This discovery (he observes) set Harvey to work upon the use of the heart and vascular system in animals, and, in the course of some years, he was so happy as to discover, and to prove beyond all possibility of doubt, the circulation of the blood." He afterwards expresses his astonishment that this discovery should have been left for Harvey; adding, that " Providence meant to reserve it for him, and would not let men see what was before them, nor understand what they read." (Hunter's Introductory Lectures, p. 42. et seq.)
Whatever opinion be formed on this point, Dr. Hunter's remarks are valuable, as an additional proof of the regard paid by anatomists to Final Causes, in the study of physio. logy.
See also Haller, Elem. Physiolog. Tom. I. p. 204.
"not take it for the effects of chance; and, in some cases, the "method itself is different, that we might see it is not the effect of "surd necessity.""*
The study of comparative anatomy leads, at every step, so directly and so manifestly to the same conclusion, that even those physiologists who had nothing in view but the advancement of their own science, unanimously agree in recommending the dissection of animals of different kinds, as the most effectual of all helps for ascertaining the functions of the various organs in the human frame; -tacitly assuming, as an incontrovertible truth, that, in proportion to the variety of means by which the same effect is accomplished, the presumption increases, that this effect was an end in the contemplation of the artist. "The intention of nature (says one author) "in the formation of the different parts, can no where be so well "learned as from comparative anatomy; that is, if we would under"stand physiology, and reason on the functions of the animal econo"my, we must see how the same end is brought about in other "species. We must contemplate the part or organ in different "animals; its shape, position, and connexion with the other parts;
Inquiry into the Nature of the Human Soul, Vol. I. p. 136. (3d ed.)
The following passage from an old English divine may be of use for the farther illustra tion of this argument. I quote it with the greater confidence, as I find that the most eminent and original physiologist of the present age (M. Cuvier) has been led, by his enlightened researches concerning the laws of the animal economy, into a train of thinking strikingly similar.
Mau is always mending and altering his works; but nature observes not the same tenor, because her works are so perfect, that there is no place for amendments, nothing that can be reprehended. The most sagacious men in so many ages, have not been able to find any flaw in these divinely contrived and formed machines; no blot or error in this great volume of the world, as if any thing had been an imperfect essay at the first; nothing that can be altered for the better; nothing but if it were altered would be marred. This could not have been, had man's body been the work of chance, and not counsel and providence. Why should there be constantly the same parts? Why should they retain constantly the same places? Nothing so contrary as constancy and chance. Should I see a man throw the same number a thousand times together upon but three dice, could you persuade me that this were accidental, and that there was no necessary cause for it? How much more incredible then is it, that constancy in such a variety, such a multiplicity of parts, should be the result of chance? Neither yet can these works be the effects of Necessity or Fate, for then there would be the same constancy observed in the smaller as well as in the larger parts and vessels; whereas there we see nature doth, as it were, sport itself, the minute ramifications of all the vessels, veins, arteries, and nerves, infinitely varying in individuals of the same species, so that they are not in any two alike." (Ray's Wisdom of God in the Creation)
"Nature, (says Cuvier) while confining herself strictly within those limits, which the conditions necessary for existence prescribed to her, has yielded to her spontaneous fecundity wherever these conditions did not limit her operations; and without ever pass ing beyond the small number of combinations, that can be realized in the essential modi. fications of the important organs, she seems to have given full scope to her fancy in filling up the subordinate parts. With respect to these, it is not inquired, whether an individual form, whether a particular arrangement be necessary; it seems often not to have been asked, whether it be even useful, in order to reduce it to practice; it is sufficient that it be possible, that it destroy not the harmony of the whole Accordingly, as we recede from the principal organs, and approach to those of less importance, the varieties in structure and appearance become more numerous; and when we arrive at the surface of the body, where the parts the least essential, and whose injuries are the least momentous, are necessarily placed, the number of varieties is so great, that the conjoined labours of naturalists have not yet been able to give us an adequate idea of them." (Leçons d'Anatomie Comparée.)
"and observe what thence arises. If we find ONE COMMON EFFECT "constantly produced, though in a very different way, we may "safely conclude that this is the use or function of the part.-This "reasoning can never betray us, if we are but sure of the facts."
The celebrated Albinus expresses himself to the same purpose in his preface to Harvey's Exercitatio de Mo u Cordis. (1) Inc.denda “autem animalia, quibus partes illae quarum actiones quaerimus "eaedem atque homini sunt, aut certe similes iis; ex quibus sine "metu erroris judicare de illis hominis liceat. Quin et reliqua, si " modo aliquam habeant ad hominem similitudinem, idonea sunt ad "aliquod suppeditandum."
If Bacon had lived to read such testimonies as these in favour of the investigation of Final Causes; or had witnessed the discoveries to which it has led in the study of the animal economy, he would, I doubt not, have readily admitted, that it was not altogether uninteresting and unprofitable, even to the physical inquirer. Such, however, is the influence of an illustrious name, that, in direct opposition to the evidence of historical facts, the assertion of the complete strility of all these speculations is, to the present day, repeated, with undiminished confidence, by writers of unquestionable learning and talents. In one of the most noted physiological works which have lately appeared on the continent, Bacon's apothegm is cited more than once with unqualified approbation; although the author candidly owns, that it is difficult for the most reserved philosopher always to keep it steadily in view, in the course of his inquiries.†
The prejudice against final causes, so generally avowed by the most eminent philosophers of France, during the eighteenth century, was first introduced into that country by Des Cartes. It must not, however, be imagined, that, in the mind of this great man, it arose from any bias towards atheism. On the contrary, he himself tells us, that his objection to the research of uses or ends, was founded entirely on the presumptuous confidence which it seemed to argue in the powers of human reason; as if it were conceivable, that the limited faculties of man could penetrate into the counsels of Divine wisdom. Of the existence of God he conceived that a demonstrative proof was afforded by the idea we are able to form of a Being infinitely perfect, and necessarily existing; and it has with some
* Letter by an anonymous Correspondent, prefixed to Monro's Comparative Anatomy, London, 1744.
"Je regarde, avec le grand Bacon, la philosophie des causes finales comme stérile : mais il est bien difficile à l'homme le plus réservé, de n'y avoir jamais recours dans ses explications." (Rapports du Physique et du Moral de l'Homme. Par M. le Senateur Cabauis Tome 1. p. 352. Paris, 1805.)
[With the great Bacon, I regard the philosophy of final causes as useless; but it is difficult for the most careful philosopher to avoid having occasional recourse to it.]
(1) (Such animals should be dissected, whose parts, the actions of which we seek, are the same with those of man, or at least resemble his; from these we may without fear of error judge of those which belong to man. And also the parts of other animals, if they have any resemblance whatever to man, may not be without their use.]
probability been conjectured, that it was his partiality to this new argument of his own, which led him to reject the reasonings of his predecessors in support of the same conclusion.*
To this objection of Des Cartes, an elaborate, and, in my opinion, a most satisfactory reply, is to be found in the works of Mr. Boyle. The principal scope of his essay may be collected from the following short extract.
"Suppose that a countryman, being in a clear day brought into "the garden of some famous mathematician, should see there one "of those curious gnomonic instruments, that shew at once the place "of the sun in the zodiac, his declination from the equator, the day "of the month, the length of the day, &c. &c. It would indeed be "presumption in him, being unacquainted both with the mathemat❝ical disciplines, and the several intentions of the artist to pretend or think himself able to discover all the ends for which so curious "and elaborate a piece was framed: but when he sees it furnished "with a style, with horary lines and numbers, and in short with all "the requisites of a sun-dial, and manifestly perceives the shadow "to mark from time to time the hour of the day, it would be no 66 more a presumption than an errour in him to conclude, that (whatever other uses the instrument was fit or was designed for) “it is a sun-dial, that was meant to shew the hour of the day."t
"Nullas unquam rationes circa res naturales a fine, quam Deus aut natura in iis faciendis sibi proposuit, desumemus; quia non tantum debemus nobis arrogare ut ejus consiliorum participes nos esse putemus." (Princip. Pars. 1. 28.) "Dum haec perpendo attentius, occurrit primò non mihi esse mirandum si quaedam a Deo fiant quorum rationes non intelligam; nec de ejus existentia ideo esse dubitandum, quod forte quaedam alia esse experiar quae, quare, vel quomodo ab illo facta sint non comprehendo ; cum enim jam sciam naturam meam esse valde infirmam et limitatam, Dei autem naturam esse immensam, incomprehensibilem, infinitam, ex hoc satis etiam scio innumerabilia illum posse, quorum causas ignorem; atque ob hanc unicam rationem totum illud causarum genus, quod a fine peti solet in rebus physicis, nullum usum habere existimo; non enim absque temeritate me puto posse investigare fines Dei." (Meditatio Quarta.)
See note (BB.)
[We shall assume no reasonings concerning natural things from the ends which God hath proposed to himself in their creation, because we ought not to arrogate to ourselves the dignity of being partakers of his counsels In my meditations on this subject, the first consideration which occurs, is this; that it is no cause of surprize God hath cre ated many things, of whose uses I am ignorant; and that it affords no ground for doubting his existence should I discover there are many other things of which I can comprehend neither the reason nor the manner of their creation: since I plainly see that my own nature is very feeble and limited, while that of God is immense, incomprehensible, infinite. This consideration alone is sufficient to persuade me, that innumerable things are possible with Him, of whose uses I must be ignorant. For this one reason, therefore, I am of opinion, that the whole kind of causes, which in physics are usually deduced from the ENDS proposed, are altogether useless. For I am sensible, that I cannot without rashness, pretend to fathom the purposes of God.] Fourth Meditation.
In the same essay, Mr. Boyle has offered some very judicious strictures on the abuses to which the research of final causes is liable, when incautiously and presumptuously pursu ed. An abstract of these, accompanied with a few illustrations from later writers, might form an interesting chapter in a treatise of inductive logic.
The subject has been since prosecuted with considerable ingenuity by Le Sage of Gene va, who has even attempted (and not altogether without success) to lay down logical rules for the investigation of ends. To this study, which he was anxious to form into a separate science, he gave the very ill chosen name of Teleologie; a name, if I am not mistaken, first suggested by Wolfius.-For some valuable fragments of his intended work with re
With this opinion of Boyle that of Newton so entirely coincided, that (according to Maclaurin) he thought the consideration of final causes essential to true philosophy; and was accustomed to congratulate himself on the effect of his writings in reviving an attention to them, after the attempt of Des Cartes to discard them from physics. On this occasion, Maclaurin has remarked, "that, of all sort of caus66 es, final causes are the most clearly placed in our view;—and that "it is difficult to comprehend, why it should be thought arrogant to "attend to the design and contrivance that is so evidently displayed in "nature, and obvious to all men ;-to maintain for instance, that the 66 eye was made for seeing though we may not be able either to ac"count mechanically for the refraction of light in its coats, or to ex"plain how the image is propagated from the retina to the mind."* -It is Newton's own language, however, which alone can do justice to his sentiments on the present subject.
"The main business of natural philosophy is to argue from phe"nomena, without feigning hypotheses, and to deduce causes from "effects till we come to the very first cause, which certainly is not "mechanical; and not only to unfold the mechanism of the world, "but chiefly to resolve these and such like questions: Whence is it "that Nature does nothing in vain; and whence arises all that order "and beauty which we see in the world?-How came the bodies of ani"mals to be contrived with so much art, and for what ends were their "several parts? Was the eye contrived without skill in optics, and the 66 ear without knowledge of sounds?"†
In multiplying these quotations, I am well aware that authorities are not arguments; but when a prejudice, to which authority alone has given currency, is to be combated, what other refutation is likely to be effectual?
After all, it were to be wished that the scholastic phrase final cause could, without affectation, be dropped from our philosophical vocabulary; and some more unexceptionable mode of speaking substituted instead of it. In this elementary work, I have not presumed to lay aside entirely a form of expression consecrated in the writings of Newton, and of his most eminent followers; but I am fully sensible of its impropriety, and am not without hopes that I may contribute something to encourage the gradual disuse of it, by the indiscriminate employment of the words ends and uses to convey the same idea. Little more perhaps than the general adoption of one or other of these terms is necessary, to bring candid and reflecting minds to a uniformity of language as well as of sentiment on the point in question.
It was before observed, with respect to anatomists, that all of them without exception, whether professedly friendly or hostile to
spect to it, see the Account of his Life and Writings by his friend M. Prevost. (Geneva, 1805.)
• Account of Newton's Philosophical Discoveries, Book I. Chap. ii.
+ Newton's Optics, Query 28.