Page:Popular Science Monthly Volume 76.djvu/41

Rh form of supernaturalism. It is failure to recognize that by its essential nature physical science can deal with causation only piecemeal; that it can only grasp causes one by one and can never get them all. Absolutism is supernaturalism, and under whatever disguise is the seemingly everlasting and implacable foe, not merely of inductive science, but of rational conduct. Would that somebody might set forth this truth in words so hot that they should burn themselves ineffacably into the philosophy, the science and the daily round of common life of our and of all future generations of men! With what serenity some of our best accredited men of science are themselves striving, and advising the neophytes in science to strive, for the solution of ultimate problems! So long as this is so there is necessity for, and will surely always be, theosophy, christian science and the whole retinue of psychic absolutisms. The one brand of finality is but the counterpoise of the other.

Though still in the second stage of idea-development as regards natural selection, a few important truths about the process are being revealed to us that Darwin overlooked, or did not sufficiently emphasize. In the first place, while he soon saw that natural selection could not be the sole cause of evolution, and while he recognized it to be a cause of a general nature, he never grasped in its full meaning the truth that there are not one, nor a few, nor even many, but literally an infinite number of causes at work in the production of species.

It is curious, once one comes to think of it, that Darwin and the rest of us should have talked so long and so absorbedly about one or a few "factors" of evolution when the demands of rigorous science are that there shall be at least as many causes as there are species. Were this not so the same cause would produce different effects, and that would make biology a hocus-pocus indeed. Supernatural causes would be quite as amenable to science as such natural ones. Trouble has befallen us here from not having listened with due attention to what David Hume has told us about causes. His definition of a cause as "an object followed by another, where, if the first had not been, the second never had existed," has not sunk deeply enough into our minds.

The course by which we have seemed to keep out of this limbo has been exactly one element in our discomfiture. We have said "Why, to be sure natural selection always takes variation and heredity for granted. Darwin made that clear enough." But when we make the causes of evolution our problem, why not face the music squarely? Why not make sure of the causes first and classify and name them afterwards? That is the way we proceed in systematic botany and zoology.

The truth is, natural selection itself is a great bundle of causes some of which are different in each particular case to which the bundle applies, so must be separately investigated for each particular species.

Does any Allmacht natural selectionist believe in his heart of hearts