He writes to Lyell in 1859, “Why I like the term is that it is constantly used in all works on breeding.”
Writing to H. G. Bronn in 1860, he explains his motives with great clearness and force:—
“Several scientific men have thought the term ‘Natural Selection’ good, because its meaning is not obvious, and each man could not put on it his own interpretation, and because it at once connects variation under domestication and nature.... Man has altered, and thus improved the English race-horse by selecting successive fleeter individuals; and I believe, owing to the struggle for existence, that similar slight variations in a wild horse, if advantageous to it, would be selected or preserved by nature; hence Natural Selection.”
In 1866 he wrote to Wallace, comparing the term with that which we owe to Herbert Spencer:—
“I fully agree with all that you say on the advantages of H. Spencer’s excellent expression of ‘the survival of the fittest.’ This however had not occurred to me till reading your letter. It is, however, a great objection to this term that it cannot be used as a substantive governing a verb; and that it is a real objection I infer from H. Spencer continually using the words, natural selection. I formerly thought, probably in an exaggerated degree, that it was a great advantage to bring into connection natural and artificial selection; this indeed led me to use a term in common, and I still think it some advantage.... The term Natural Selection has now been so largely used abroad and at home, that I doubt whether it could be given up, and with all its faults I should be sorry to see the attempt made. Whether it will be rejected must now depend ‘on the survival of the fittest.’ As in time the term must grow intelligible the objections to its use will grow weaker and weaker. I doubt whether the use of any term would have made the subject intelligible to some minds, clear as it is to others; for do we not see even to the present day Malthus on Population absurdly misunderstood? This reflection about Malthus has often comforted me when I have been vexed at the mis-statement of my own views.”
A large number of critics not only failed to understand natural selection, but they asserted that it was precisely the same theory as that advanced by Lamarck or one of the other writers on evolution before Darwin. This seems almost incredible to us at the present day, when the biological world is divided into two sections on the very subject, and when it is generally recognised that Lamarck’s theory would be, if it were proved to be sound, a formidable rival to natural selection as a motive cause of evolution. But the following quotations—a few among many—leave no doubt whatever upon the subject.
Evidence on this point reached Darwin almost immediately after the appearance of the “Origin.” Thus he writes to Hooker on December 14th, 1859:—
“Old J. E. Gray, at the British Museum, attacked me in fine style: ‘You have just reproduced Lamarck’s doctrine, and nothing else, and here Lyell and others have been attacking him for twenty years, and because you ... say the very same thing, they are all coming round; it is the most ridiculous inconsistency,’ &c. &c.”
In the following year, Wilberforce, Bishop of Oxford, writing in the Quarterly Review for July, 1860, appeals to Lyell,
“in order that with his help this flimsy speculation may be as completely put down as was what in spite of all denials we must venture to call its twin though less-instructed brother, the ‘Vestiges of Creation.’”