“I entirely agree with you that the difficulties on my notions are terrific; yet having seen what all the Reviews have said against me, I have far more confidence in the general truth of the doctrine than I formerly had. Another thing gives me confidence—viz. that some who went half an inch with me now go further, and some who were bitterly opposed are now less bitterly opposed. And this makes me feel a little disappointed that you are not inclined to think the general view in some slight degree more probable than you did at first. This I consider rather ominous. Otherwise I should be more contented with your degree of belief. I can pretty plainly see that if my view is ever to be generally adopted, it will be by young men growing up and replacing the old workers, and then young ones finding that they can group facts and search out new lines of investigation better on the notion of descent than on that of creation.”
In 1863 Huxley delivered a course of lectures to working men on “The Causes of the Phenomena of Organic Nature”; here, too, he expressed his opinions about natural selection with great clearness and force. These lectures are reprinted as the concluding part of “Darwiniana,” and the references are to the pages of that volume of his collected essays.
On page 464 we read—
“Here are the phenomena of Hybridism staring you in the face, and you cannot say, ‘I can, by selective modification, produce these same results.’ Now, it is admitted on all hands, at present, so far as experiments have gone, it has not been found possible to produce this complete physiological divergence by selective breeding.... If we were shewn that this must be the necessary and inevitable results of all experiments, I hold that Mr. Darwin’s hypothesis would be utterly shattered.”
He then goes on to show that this is very far from proved, and concludes (page 466)—
“that though Mr. Darwin’s hypothesis does not completely extricate us from this difficulty at present, we have not the least right to say it will not do so.”
A passage on page 467 shows that Huxley placed natural selection infinitely higher than any other attempt to account for evolution, and indeed that he regarded all other attempts with scorn.
“I really believe that the alternative is either Darwinism or nothing, for I do not know of any rational conception or theory of the Organic universe which has any scientific position at all beside Mr. Darwin’s.... Whatever may be the objections to his views, certainly all other theories are absolutely out of court.”
On page 468 he continues—
“But you must recollect that when I say I think it is either Mr. Darwin’s hypothesis or nothing; that either we must take his view, or look upon the whole of organic nature as an enigma, the meaning of which is wholly hidden from us; you must understand that I mean that I accept it provisionally, in exactly the same way as I accept any other hypothesis.”