It was evident that such facts as these, as well as many others, could only be explained on the supposition that species gradually become modified; and the subject haunted me. But it was equally evident that neither the action of the surrounding conditions, nor the will of the organisms (especially in the case of plants), could account for the innumerable cases in which organisms of every kind are beautifully adapted to their habits of life; for instance, a woodpecker or a tree-frog to climb trees, or a seed for dispersal by hooks or plumes. I had always been much struck by such adaptations, and until these could be explained it seemed to me almost useless to endeavor to prove by indirect evidence that species have been modified.

After my return to England it appeared to me that by following the example of Lyell in Geology, and by collecting all facts which bore in any way on the variation of animals and plants under domestication and nature, some light might perhaps be thrown on the whole subject. My first note-book was opened in July 1837. I worked on true Baconian principles; and without any theory collected facts on a wholesale scale, more especially with respect to domesticated productions, by printed inquiries, by conversation with skillful breeders and gardeners, and by extensive reading. When I see the list of books of all kinds which I read and abstracted, including whole series of Journals and Transactions, I am surprised at my industry. I soon perceived that selection was the keystone of man's success in making useful races of animals and plants. But how selection could be applied to organisms living in a state of nature, remained for some time a mystery to me.

In October 1838—that is, fifteen months after I had begun my systematic inquiry—I happened to read for amusement 'Malthus on Population'; and being well prepared to appreciate the struggle for existence which everywhere goes on from long-continued observation of the habits of animals and plants, it at once struck me that under these circumstances favorable variations would tend to be preserved, and unfavorable ones to be destroyed. The result of this would be the formation of new species. Here then I had at last got a theory by which to work; but I was so anxious to avoid prejudice that I determined not for some time to write even the briefest sketch of it. In June 1842 I first allowed myself the satisfaction of writing a very brief abstract of my theory in pencil in thirty-five pages; and this was enlarged during the summer of 1844 into one of two hundred and thirty pages, which I had fairly copied out and still possess.

THE APE-MAN
Photogravure from a painting by Gabriel Max.
Professor Max has long been known to the greater public through those wonderful pictures in which some tragic fate, some heart-break of mankind, has found expression; but only an inner circle of intimates has known the artist as an able student of nature. He has thought much and deeply upon the existence and origin of things; and his studies in comparative anatomy have given him unusual preparation for the treatment of the present subject. The entire picture is made up of yellowish and brownish-gray tones, expressive of the twilight of the forest. The skin of the female is about the shade of that of the Southern European of to-day; that of the male is darker. The most interesting of the three figures is the young ape-mother, who reclines against a tree-trunk and offers her breast to her first-born. The expression of the face is remarkable; happiness at the possession of the child mingles with misgiving for its future. The tear which trembles upon her cheek seems indicative of the flood of tears which is to run down the history of her descendants. The father has less of this feeling, and stands upright beside his wife and child and looks down upon them with an air of pride and paternal joy. The original painting is owned by the celebrated Darwinian philosopher Ernest Haeckel of Jena.

But at that time I overlooked one problem of great importance; and it is astonishing to me, except on the principle of Columbus and his egg, how I could have overlooked it and its solution. This problem is the tendency in organic beings descended from the same stock to diverge in character as they become modified. That they have diverged greatly is obvious from the manner in which species of all kinds can be classed under genera, genera under families, families under sub-orders, and so forth: and I can remember the very spot in the road, whilst in my carriage, when to my joy the solution occurred to me; and this was long after I had come to Down. The solution, as I believe, is that the modified offspring of all dominant and increasing forms tend to become adapted to many and highly diversified places in the economy of nature.

Early in 1856 Lyell advised me to write out my views pretty fully, and I began at once to do so on a scale three or four times as extensive as that which was afterwards followed in my 'Origin of Species'; yet it was only an abstract of the materials which I had collected, and I got through about half the work on this scale. But my plans were overthrown, for early in the summer of 1858 Mr. Wallace, who was then in the Malay Archipelago, sent me an essay 'On the Tendency of Varieties to depart Indefinitely from the Original Type'; and this essay contained exactly the same theory as mine. Mr. Wallace expressed the wish that if I thought well of his essay, I should send it to Lyell for perusal.

The circumstances under which I consented, at the request of Lyell and Hooker, to allow of an abstract from my MS., together with a letter to Asa Gray dated September 5th 1857, to be published at the same time with Wallace's essay, are given in the 'Journal of the Proceedings of the Linnean Society,' 1858, page 45. I was at first very unwilling to consent, as I thought Mr. Wallace might consider my doing so unjustifiable, for I did not then know how generous and noble was his disposition. The extract from my MS. and the letter to Asa Gray had neither been intended for publication, and were badly written. Mr. Wallace's essay, on the other hand, was admirably expressed and quite clear. Nevertheless, our joint productions excited very little attention, and the only published notice of them which I can remember was by Professor Haughton of Dublin, whose verdict was that all that was new in them was false, and what was true was old. This shows how necessary it is that any new view should be explained at considerable length in order to arouse public attention....

My habits are methodical, and this has been of not a little use for my particular line of work. Lastly, I have had ample leisure from not having to earn my own bread. Even ill health, though it has annihilated several years of my life, has saved me from the distractions of society and amusement.