CHAPTER VI. DARWINISM IN THE STRICT SENSE.
It remains for us to consider what is essentially Darwinian in Darwinism, namely, the theory of natural selection as the determining factor in evolution. For, given the reality of evolution and descent, and that transformations from one form to another, from lower to higher, have really taken place, what was the guiding and impelling factor in evolution, what forced it forwards and upwards? It is here that the real problem of Darwinism begins. Only from this point onwards does the doctrine of evolution, which is not in itself necessarily committed to any theory of the factors, become definitely Darwinian or anti-Darwinian. And it is this problem that is mainly concerned in the discussions taking place to-day as to whether Darwin was right, or whether Darwinism as a hypothesis has not broken down.
The most characteristic feature of Darwin’s theory was “natural teleology,” that is, the explanation of what is apparently full of purpose and plan in the world, purely as the necessary consequence of very simple conditions, without purpose or any striving after an aim. He sought to show that evolution and ascent can be realised through purely “natural” causes, that this world of life, man included, must have come about, but not because it was intended so to do. In this sense, indeed, his doctrine is an attempt to do away with teleology. But in another sense it is so even more emphatically. The world, and especially the world of life, is undoubtedly full of what is _de facto_ purposive. The living organism, as a whole and in every one of its parts, is marvellously adapted to the end of performing its functions, maintaining its own life and reproducing. Every single living being is a miracle of inexhaustible adaptations to an end. Whence came these? They, too, are products, unsought for, unintended, and yet necessary, and coming about “of themselves,” that is without teleological or any supernatural guiding principles. To eliminate purpose and the purposive creating and guiding activity of transcendental principles from interpretations of nature, and to introduce purely naturalistic principles—“principles of chance,” if we understand chance in this connection not as opposed to necessity, but to plan and purpose—this is the aim of the Darwinian theory. And it only becomes definitely anti-theological because it is anti-teleological.