In the face of all the facts, therefore, I find it impossible to recognise as valid any inference which is drawn from the existence of our moral sense to the existence of a God; although, of course, all inferences drawn from the existence of our moral sense to the character of a God already believed to exist remain unaffected by the foregoing considerations.[[17]]
[CHAPTER III].
THE ARGUMENT FROM DESIGN.
[§ 23]. The argument from Design, as presented by Mill, is merely a resuscitation of it as presented by Paley. True it is that the logical penetration of the former enabled him to perceive that the latter had "put the case much too strongly;" although, even here, he has failed to see wherein Paley's error consisted. He says:—"If I found a watch on an apparently desolate island, I should indeed infer that it had been left there by a human being; but the inference would not be from the marks of design, but because I already know by direct experience that watches are made by men." Now I submit that this misses the whole point of Paley's meaning; for it is evident that there would be no argument at all unless this author be understood to say what he clearly enough expresses, viz., that the evidence of design supposed to be afforded by the watch is supposed to be afforded by examination of its mechanism only, and not by any previous knowledge as to how that particular mechanism called a watch is made. Paley, I take it, only chose a watch for his example because he knew that no reader would dispute the fact that watches are constructed by design: except for the purpose of pointing out that mechanism is in some cases admitted to be due to intelligence, for all the other purposes of his argument he might as well have chosen for his illustration any case of mechanism occurring in nature. What the real fallacy in Paley's argument is, is another question, and this I shall now endeavour to answer; for, as Mill's argument is clearly the same in kind as that of Paley and his numberless followers, in examining the one I am also examining the other.
[§ 24]. In nature, then, we see innumerable examples of apparent design: are these of equal value in testifying to the presence of a designing intelligence as are similar examples of human contrivance, and if not, why not? The answer to the first of these questions is patent. If such examples were of the same value in the one case as they are in the other, the existence of a Deity would be, as Paley appears to have thought it was, demonstrated by the fact. A brief and yet satisfactory answer to the second question is not so easy, and we may best approach it by assuming the existence of a Deity. If, then, there is a God, it by no means follows that every apparent contrivance in nature is an actual contrivance, in the same sense as is any human contrivance. The eye of a vertebrated animal, for instance, exhibits as much apparent design as does a watch; but no one—at the present day, at least—will undertake to affirm that the evidence of divine thought furnished by one example is as conclusive as is the evidence of human thought furnished by the other—and this even assuming a Deity to exist. Why is this? The reason, I think, is, that we know by our personal experience what are our own relations to the material world, and to the laws which preside over the action of physical forces; while we can have no corresponding knowledge of the relations subsisting between the Deity and these same objects of our own experience. Hence, to suppose that the Deity constructed the eye by any such process of thought as we know that men construct watches, is to make an assumption not only incapable of proof, but destitute of any assignable degree of likelihood. Take an example. The relation in which a bee stands to the external world is to a large extent a matter of observation, and, therefore, no one imagines that the formation of its scientifically-constructed cells is due to any profound study on the bee's part. Whatever the origin of the cell-making instinct may have been, its nature is certainly not the same as it would have been in man, supposing him to have had occasion to construct honeycombs. It may be said that the requisite calculations have been made for the bees by the Deity; but, even if this assumption were true, it would be nothing to the point, which is merely that even within the limits of the animal kingdom the relations of intelligence to the external world are so diverse, that the same results may be accomplished by totally different intellectual processes. And as this example is parallel to the case on which we are engaged in everything save the observability of the relations involved, it supplies us with the exact measure of the probability we are trying to estimate. Hence it is evident that so long as we remain ignorant of the element essential to the argument from design in its Paleyerian form—viz., knowledge or presumption of the relations subsisting between an hypothetical Deity and his creation—so long must that argument remain, not only unassignably weak, but incapable of being strengthened by any number of examples similar in kind.
[§ 25]. To put the case in another way. The root fallacy in Paley's argument consisted in reasoning from a particular to an universal. Because he knew that design was the cause of adaptation in some cases, and because the phenomena of life exhibited more instances of adaptation than any other class of phenomena in nature, he pointed to these phenomena as affording an exceptional kind of proof of the presence in nature of intelligent agency. Yet, if it is admitted—and of this, even in Paley's days, there was a strong analogical presumption—that the phenomena of life are throughout their history as much subject to law as are any other phenomena whatsoever,—that the method of the divine government, supposing such to exist, is the same here as elsewhere; then nothing can be clearer than that any amount of observable adaptation of means to ends within this class of phenomena cannot afford any different kind of evidence of design than is afforded by any other class of phenomena whatsoever. Either we know the relations of the Deity to his creation, or we do not. If we do, then we must know whether or not every physical change which occurs in accordance with law—i.e., every change occurring within experience, and so, until contrary evidence is produced, presumably every change occurring beyond experience—was separately planned by the Deity. If we do not, then we have no more reason to suppose that any one set of physical changes rather than another has been separately planned by him, unless we could point (as Paley virtually pointed) to one particular set of changes and assert, These are not subject to the same method of divine government which we observe elsewhere, or, in other words, to law. If it is retorted that in some way or other all these wonderful adaptations must ultimately have been due to intelligence, this is merely to shift the argument to a ground which we shall presently have to consider: all we are now engaged upon is to show that we have no right to found arguments on the assumed mode, manner, or process by which the supposed intelligence is thought to have operated. We can here see, then, more clearly where Paley stumbled. He virtually assumed that the relations subsisting between the Deity and the universe were such, that the exceptional adaptations met with in the organised part of the latter cannot have been due to the same intellectual processes as was the rest of the universe—or that, if they were, still they yielded better evidence of having been due to these processes than does the rest of the universe. And it is easy to perceive that his error arose from his pre-formed belief in special creation. So long as a man regards every living organism which he sees as the lineal descendant of a precisely similar organism originally struck out by the immediate fiat of Deity, so long is he justified in holding his axiom, "Contrivance must have had a contriver." For "adaptation" then becomes to our minds the synonym of "contrivance"—it being utterly inconceivable that the numberless adaptations found in any living organism could have resulted in any other way than by intelligent contrivance, at the time when this organism was in the first instance suddenly introduced into its complex conditions of life. Still, as an argument, this is of course merely reasoning in a circle: we adopt a hypothesis which presupposes the existence of a Deity as the first step in the proof of his existence. I do not say that Paley committed this error expressly, but merely that if it had not been for his pre-formed conviction as to the truth of the special-creation theory, he would probably not have written his "Natural Theology."
[§ 26]. Thus let us take a case of his own choosing, and the one which is adduced by him as typical of "the application of the argument." "I know of no better method of introducing so large a subject than that of comparing a single thing with a single thing; an eye, for example, with a telescope. As far as the examination of the instrument goes, there is precisely the same proof that the eye was made for vision as there is that the telescope was made for assisting it. They are both made upon the same principles, both being adjusted to the laws by which the transmission and refraction of rays of light are regulated. I speak not of the origin of the laws themselves; but these laws being fixed, the construction in both cases is adapted to them. For instance: these laws require, in order to produce the same effect, that the rays of light, in passing through water into the eye, should be refracted by a more convex surface than when it passes out of air into the eye. Accordingly we find that the eye of a fish, in that part of it called the crystalline lens, is much rounder than the eye of terrestrial animals. What plainer manifestation of design can there be than this difference?" But what, let us ask, is the proximate cause of this difference? 'The immediate volition of the Deity, manifested in special creation,' virtually answers Paley; while we of to-day are able to reply, 'The agency of natural laws, to wit, inheritance, variation, survival of the fittest, and probably of other laws as yet not discovered.' Now, of course, according to the former of these two premises, there can be no more legitimate conclusion than that the difference in question is due to intelligent and special design; but, according to the other premise, it is equally clear that no conclusion can be more unwarranted; for, under the latter view, the greater rotundity of the crystalline lens in a fish's eye no more exhibits the presence of any special design than does the adaptation of a river to the bed which it has itself been the means of excavating. When, therefore, Paley goes on to ask:—"How is it possible, under circumstances of such close affinity, and under the operation of equal evidence, to exclude contrivance from the case of the eye, yet to acknowledge the proof of contrivance having been employed, as the plainest and clearest of all propositions, in the case of the telescope?" the answer is sufficiently obvious, namely, that the "evidence" in the two cases is not "equal;"—any more than is the existence, say, of the Nile of equal value in point of evidence that it was designed for traffic, as is the existence of the Suez Canal that it was so designed. And the mere fact that the problem of achromatism was solved by "the mind of a sagacious optician inquiring how this matter was managed in the eye," no more proves that "this could not be in the eye without purpose, which suggested to the optician the only effectual means of attaining that purpose," than would the fact, say, of the winnowing of corn having suggested the fanning-machine prove that air currents were designed for the purpose of eliminating chaff from grain. In short, the real substance of the argument from Design must eventually merge into that which Paley, in the above-quoted passage, expressly passes over—viz., "the origin of the laws themselves;" for so long as there is any reason to suppose that any apparent "adaptation" to a certain set of "fixed laws" is itself due to the influence of other "fixed laws," so long have we as little right to say that the latter set of fixed laws exhibit any better indications of intelligent adaptation to the former set, than the former do to that of the latter—the eye to light, than light to the eye. Hence I conceive that Mill is entirely wrong when he says of Paley's argument, "It surpasses analogy exactly as induction surpasses it," because "the instances chosen are particular instances of a circumstance which experience shows to have a real connection with an intelligent origin—the fact of conspiring to an end." Experience shows as this, but it shows us more besides; it shows us that there is no necessary or uniform connection between an "intelligent origin" and the fact of apparent "means conspiring to an [apparent] end." If the reader will take the trouble to compare this quotation just made from Mill, and the long train of reasoning that follows, with an admirable illustration in Mr. Wallace's "Natural Selection," he will be well rewarded by finding all the steps in Mr. Mill's reasoning so closely paralleled by the caricature, that but for the respective dates of publication, one might have thought the latter had an express reference to the former.[[18]] True, Mr. Mill closes his argument with a brief allusion to the "principle of the survival of the fittest," observing that "creative forethought is not absolutely the only link by which the origin of the wonderful mechanism of the eye may be connected with the fact of sight." I am surprised, however, that a man of Mr. Mill's penetration did not see that whatever view we may take as to "the adequacy of this principle (i.e., Natural Selection) to account for such truly admirable combinations as some of those in nature," the argument from Design is not materially affected. So far as this argument is concerned, the issue is not Design versus Natural Selection, but it is Design versus Natural Law. By all means, "leaving this remarkable speculation (i.e., Mr. Darwin's) to whatever fate the progress of discovery may have in store for it," and it by no means follows that "in the present state of knowledge the adaptations in nature afford a large balance of probability in favour of creation by intelligence." For whatever we may think of this special theory as to the mode, there can be no longer any reasonable doubt, "in the present state of our knowledge," as to the truth of the general theory of Evolution; and the latter, if accepted, is as destructive to the argument from Design as would the former be if proved. In a word, it is the fact and not the method of Evolution which is subversive of Teleology in its Paleyerian form.
[§ 27]. We have come then to this:—Apparent intellectual adaptations are perfectly valid indications of design, so long as their authorship is known to be confined to human intelligence; for then we know from experience what are our relations to these laws, and so in any given case can argue à posteriori that such an adaptation to such a set of laws by such an intelligence can only have been due to such a process. But when we overstep the limits of experience, we are not entitled to argue anything à priori of any other intelligence in this respect, even supposing any such intelligence to exist. The analogy by which the unknown relations are inferred from the known is "infinitely precarious;" seeing that two of the analogous terms—to wit, the divine intelligence and the human—may differ to an immeasurable extent in their properties—nay, are supposed thus to differ, the one being supposed omniscient, omnipotent, &c., and the other not. And, as a final step, we may now see that the argument from Design, in its last resort, resolves itself into a petitio principii. For, ultimately, the only point which the analogical argument in question is adduced to prove is, that the relations subsisting between an Unknown Cause and certain physical forces are so far identical with the relations known to subsist between human intelligence and these same forces, that similar intellectual processes are required in the two cases to account for the production of similar effects—and hence that the Unknown Cause is intelligent. But it is evident that the analogy itself can have no existence, except upon the presupposition that these two sets of relations are thus identical. The point which the analogy is adduced to prove is therefore postulated by the fact of its being adduced at all, and the whole argument resolves itself into a case of petitio principii.