Now by the term Evolution is meant to be included the processes of Organic Evolution, Natural Selection, and the Survival of the Fittest. The former may be described as meaning that all the different forms of life now existing, or that ever have existed on this earth, are the descendants of earlier and less developed forms, and those again of simpler ones; and so on, till we get back to the earliest form of life, whatever that may have been.
And the theories of Natural Selection and the Survival of the Fittest explain how this may have taken place. For among the slight modifications that would most likely occur in every organism, those, and only those, would be perpetuated which were of advantage to it in the struggle for existence. And they would in time, it is assumed, become hereditary in its descendants, and thus higher forms of life would be gradually produced. And the value of these theories is that they show how Organic Evolution may have taken place without involving any sudden change, such as a monkey giving birth to a man. We must remember, however, that the subject is far from settled; and even now naturalists are beginning to doubt whether all the modifications were in reality very slight. But still, speaking broadly, this is the theory we have to discuss.
It will, of course, be noticed that Evolution is thus a process, and not a cause. It is the method in which certain changes have been brought about, and not the cause which brings them about. Every slight modification must have been caused somehow. When such modifications were caused, then Natural Selection can explain how the useful ones alone were perpetuated, but it cannot explain how the modifications themselves arose. On the contrary, it supposes them as already existing, otherwise there would be nothing to select from. Natural Selection, then, rather weeds than plants, and would be better described as Natural Rejection. It merely shows how, as a rule, among the various modifications in an organism, some good and some bad, the useless ones would disappear, and the useful ones would remain; in other words, how the fittest would survive. But this survival of the fittest does not explain in the slightest degree how the fitness arose. If, as an extreme example, out of a hundred animals, fifty had eyes and fifty had not, it is easy to understand how those that had eyes would be more likely to have descendants; but this does not explain how they first got eyes. And the same applies in other cases.
How, then, did the variations in each organism first arise? In common language they may be ascribed to chance; but, strictly speaking, such a thing is impossible. The word chance is merely a convenient term for the results of certain forces of nature when we are unable to calculate them. Chance, then, must be excluded; and there seem to be only two alternatives. Either the organisms in nature possessed free will, and acted as they did voluntarily; or else they did not possess free will, and acted as they did necessarily. The former theory will be examined later on; the latter is the one we are now considering.
(2.) The effect of Evolution.
How then would this theory affect our previous conclusion that the Creator designed all the organs of nature, such as the eye, and hence presumably the whole of the universe? As we shall see, it only confirms it. For to put it plainly, if all free will on the part of the organisms is excluded, so that they were all bound to act exactly as they did, it is clear that the earth and all it contains is like a vast mass of machinery. And however complicated its parts, and however much they may act on one another, and however long they may take in doing so, yet if in the end they produce an organ showing design, this must have been foreseen and intended by the Maker of the machinery. In the same way if a mass of machinery after working for a long time eventually turned out a watch, we should have no hesitation in saying that whoever made the machinery, and set it going, intended it to do so. And is the inference less clear, if it not only turned out a watch, but a watchmaker as well, and everything else that exists on this planet?
All then that evolution does is this. It shows that the whole of nature forms such a long and continuous process; that if the end has been foreseen at all, it must have been foreseen from the beginning. In other words, just as the Unity of Nature shows that if anything has been designed, everything has been designed; so Evolution shows that if it has been designed at all, it has been designed from the beginning. We must hence conclude that the organs in nature, such as the eye, which undoubtedly show design, were not designed separately or as after-thoughts, but were all included in one grand design from the beginning. And this can only increase our admiration for the Designer. Thus evolution, even in its most extreme and automatic form, cannot get rid of a Designer. Still less can it do so, if (as is probable) it is not automatic at all; but is due to the continuous action of the Creator, who is what is called immanent in nature, and directs every step.
It should be noticed, moreover, that in one respect evolution rather increases the evidence of design. For if, to take a single example, a human hand has been evolved from a monkey's foot merely by the monkey using it as a hand, and taking hold of things; it increases the amount of design which must have been spent on the foot to enable it to do so. And if all the organs in nature have been evolved in this way from simpler ones, it increases the amount of design which must have been spent on those simpler ones to an extent which is practically infinite.
Thus Evolution implies a previous Involution; since all forms of life must have been involved in the first form before they could be evolved from it; so that creation by evolution is more wonderful than creation by direct manufacture. And it seems to many to be a far nobler conception of the Creator that He should obtain all the results He desired, by one grand system of evolution, rather than by a large number of separate creations. For then the method in which the results were obtained would be as marvellous, and show as much wisdom and foresight as the results themselves; and each would be worthy of the other. Evolution, then, seems to be the highest form of creation; and so far from destroying the present argument, it only destroys its difficulties, by showing that every single part of every single organism may have been designed, and yet in a manner worthy of the great Creator.
Nor is the conclusion altered if we carry back the process of evolution, and assume that the earliest form of life was itself evolved from some previous form of inanimate matter; and this again from a simpler one, and so on till we get back to the original form of matter, whatever that may have been. For if the results as we now see them show design, then the argument for a Designer is not weakened, but our ideas of His skill are still further increased, if we believe that they were already secured when our earth was merely a nebula.