ch. ii.] 'ORIGIN OF SPECIES.' 43 



stances favourable variations would tend to be preserved and 

 unfavourable 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 ab- 

 stract of my theory in pencil in 35 pages ; and this was en- 

 larged during the summer of 1844 into one of 230 pages, 

 which I had fairly copied out and still possess. 



But at that time I overlooked one problem of great im- 

 portance ; and it is astonishing to me, except on the princi- 

 ple 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 charac- 

 ter 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 remem- 

 ber 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 diversi- 

 fied 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 re- 

 quest of Lyell and Hooker to allow of an abstract from my 

 MS., together with a letter to Asa Gray, dated September 5, 

 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, p. 45. I was at first very unwilling to con- 

 sent, as I thought Mr. Wallace might consider my doing so 



