Here, again, it is not use and disuse which Mr. Darwin declares himself to have undervalued, but spontaneous variations. The sentence just given is one of the most confusing I ever read even in the works of Mr Darwin. It is the essence of his theory that the “numerous successive, slight, favourable variations,” above referred to, should be fortuitous, accidental, spontaneous; it is evident, moreover, that they are intended in this passage to be accidental or spontaneous, although neither of these words is employed, inasmuch as use and disuse and the action of the conditions of existence, whether direct or indirect, are mentioned specially as separate causes which purvey only the minor part of the variations from among which nature selects. The words “that is, in relation to adaptive forms” should be omitted, as surplusage that draws the reader’s attention from the point at issue; the sentence really amounts to this—that modification has been effected _chiefly through selection_ in the ordinary course of nature _from among spontaneous variations_, _aided in an unimportant manner by variations which quâ us are spontaneous_. Nevertheless, though these spontaneous variations are still so trifling in effect that they only aid spontaneous variations in an unimportant manner, in his earlier editions Mr. Darwin thought them still less important than he does now.
This comes of tinkering. We do not know whether we are on our heads or our heels. We catch ourselves repeating “important,” “unimportant,” “unimportant,” “important,” like the King when addressing the jury in “Alice in Wonderland;” and yet this is the book of which Mr. Grant Allen { 163a} says that it is “one of the greatest, and most learned, the most lucid, the most logical, the most crushing, the most conclusive, that the world has ever seen. Step by step, and principle by principle, it proved every point in its progress triumphantly before it went on to the next. So vast an array of facts so thoroughly in hand had never before been mustered and marshalled in favour of any biological theory.” The book and the eulogy are well mated.
I see that in the paragraph following on the one just quoted, Mr. Allen says, that “to the world at large Darwinism and evolution became at once synonymous terms.” Certainly it was no fault of Mr. Darwin’s if they did not, but I will add more on this head presently; for the moment, returning to Mr. Darwin, it is hardly credible, but it is nevertheless true, that Mr Darwin begins the paragraph next following on the one on which I have just reflected so severely, with the words, “It can hardly be supposed that a false theory would explain in so satisfactory a manner as does the theory of natural selection, the several large classes of facts above specified.” If Mr. Darwin found the large classes of facts “satisfactorily” explained by the survival of the luckiest irrespectively of the cunning which enabled them to turn their luck to account, he must have been easily satisfied. Perhaps he was in the same frame of mind as when he said { 164a} that “even an imperfect answer would be satisfactory,” but surely this is being thankful for small mercies.