XIV
ORGANIC EVOLUTION
WE have now considered the question of Evolution in the larger and more fundamental signification of the term to which, as we noted at starting, very different meanings are attached; and at this stage of our discussion it will be convenient to sum up the main conclusions at which we have arrived.
It is, in the first place, unwarrantable to pretend that the discoveries of modern Science, brilliant and marvellous as they undoubtedly are, have thrown any light upon the origin of the Material Universe, or of its forces, or of the laws according to which its operations proceed. Nor has Science anything to tell as to the origin of life, of sensation, or of reason. Nothing as yet discovered by her, or which she can discern any prospect of discovering, adds aught to our knowledge regarding such points as these.
Therefore, to say that the doctrine of Evolution as affirmed by Science, explains the existence of the world we know, is untrue and unscientific.
Moreover, we have seen that, as a factor without which the Order of Nature is unintelligible, the First[{141}] Cause to which her existence is owing must be possessed of Intelligence, determining her processes according to its purposes. Hence it follows that no system of philosophy satisfies our reason which would find the ultimate explanation of all things in the forces of matter themselves which it is the province of Science to investigate.
On the other hand, in maintaining that Purpose must needs have acted, we do not assume to pronounce as to the manner of its action. To say that Purpose rules every detail in the making or development of the universe, does not by any means signify that it interferes at every step with the laws of Nature. Rather, these laws are the expression of Purpose,—its machinery to secure its designed result. Assuming, for instance, the primeval existence of Professor Huxley's cosmic nebula, so constituted that the actual world was bound naturally to issue from it, as does a chicken from an egg, or an oak from an acorn,—while we find it inconceivable that such a piece of mechanism should originate without an intelligence to design it,—we have no difficulty in supposing that intelligence to have exhibited itself once for all at the first beginning, and to have fashioned the actual world by shaping the causes or conditions by which it was to be produced, thus making everything, not directly and immediately but as St. Augustine held "causaliter et seminaliter."
There remains for consideration Evolution in its[{142}] narrower sense, in which its operations are restricted to organic nature, such Evolution being commonly, but incorrectly, identified with "Darwinism." Understood thus, "Evolution" signifies no more than that the various species of animals and plants have descended genetically one from another, through a graduated series of intermediate forms which link them together. Darwinism is one particular mode of explaining how such transformations may be accounted for,—namely, by what is known as "Natural Selection." The theory of Evolution, as thus concerned with Organic life in particular, is compendiously described as "Transformism," under which head Darwinism is evidently included.
Transformism makes no pretence to account for the origin of life, whether animal or vegetable. Living things must exist before any question arises as to their transmutation. But, given the existence of life, Transformists undertake in the first place to show that Organic Evolution has, as a matter of fact, occurred, and is still in process of occurrence; and secondly, to exhibit the manner in which this process is actually worked out. As to the first point, all Transformists, whether Darwinians or others, are necessarily at one, for the fact of Evolution is equally essential for every explanation of its method. It is when they come to explain in what manner evolutionary transformations have been wrought that Transformists divide themselves into various schools, each of which relies upon some particular factor to furnish the required explanation.[{143}] Thus besides Darwinians pure and simple, there are neo-Darwinians, Lamarckians, neo-Lamarckians, Weismannists, and others, ascribing the results to physiological selection, sexual-selection, or other forces, rather than natural selection. Of such systems, however, excepting only Darwinism, it will be unnecessary to speak in particular. The great fundamental question is whether genetic Evolution be really established as a fact,—which, as has been said, equally affects them all—and if it be advisable to treat more in detail of Darwinism, it is not because this does not hold good of it as of the rest—but because this particular system has obtained such a position, is so much in the mouths of men, and has been made the basis of so many and such far-reaching consequences, that it is impossible to pass it by.
Much the same may indeed be said even of the assumed fact of Organic Evolution underlying all Transformist theories. This does not affect the fundamental problems with which we are concerned, and leaving untouched, as it does, the question of the origin of Life it makes even less pretence than the cosmic-nebular hypothesis just spoken of to trace the operations of Nature to their ultimate source. It might therefore appear superfluous to devote to it so much attention as, if treated at all, it must needs demand.