Page:Principia Ethica 1922.djvu/91

sense, denote a natural law, like the law of gravity. Darwin’s theory of natural selection does indeed state a natural law: it states that, given certain conditions, certain results will always happen. But Evolution, as Mr Spencer understands it and as it is commonly understood, denotes something very different. It denotes only a process which has actually occurred at a given time, because the conditions at the beginning of that time happened to be of a certain nature. That such conditions will always be given, or have always been given, cannot be assumed; and it is only the process which, according to natural law, must follow from these conditions and no others, that appears to be also on the whole a progress. Precisely the same natural laws—Darwin’s, for instance—would under other conditions render inevitable not Evolution—not a development from lower to higher—but the converse process, which has been called Involution. Yet Mr Spencer constantly speaks of the process which is exemplified by the development of man as if it had all the augustness of a universal Law of Nature: whereas we have no reason to believe it other than a temporary accident, requiring not only certain universal natural laws, but also the existence of a certain state of things at a certain time. The only laws concerned in the matter are certainly such as, under other circumstances, would allow us to infer, not the development, but the extinction of man. And that circumstances will always be favourable to further development, that Nature will always work on the side of Evolution, we have no reason whatever to believe. Thus the idea that Evolution throws important light on Ethics seems to be due to a double confusion. Our respect for the process is enlisted by the representation of it as the Law of Nature. But, on the other hand, our respect for Laws of Nature would be speedily diminished, did we not imagine that this desirable process was one of them. To suppose that a Law of Nature is therefore respectable, is to commit the naturalistic fallacy; but no one, probably, would be tempted to commit it, unless something which is respectable, were represented as a Law of Nature. If it were clearly recognised that there is no evidence for supposing Nature to be on the side of the Good, there would probably be less tendency to hold the opinion, which on other grounds is demonstrably false, that