182 DARWINISM AND HUMAN LIFE 



general idea of selection are to be found in various 

 pre-Darwinian documents,' but it was to Malthus 

 only that Darwin, who was very generous in dealing 

 with anticipations, owned any debt. He speaks 

 of this in a well-known passage in his " Autobio- 

 graphy " : " In October, 1838, 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 observations of the habits of animals 

 and plants, it at once struck me that, under these 

 circumstances, favourable variations would tend 

 to be preserved and unfavourable ones to be 

 destroyed. The result of this would be the forma- 

 tion of new species. Here, then, I had at last got a 

 theory by which to work." 



Twenty years after — Darwin having fvblished no 

 theory meanwhile — history repeated itself. Alfred 

 Eussel Wallace was collecting insects at Ternate 

 and suffering badly from fever. As he was resting 

 one day between fits, he happened to recall Malthus' 

 " Principles of Population " which he had read 

 about twelve years before — ^the first book that he 

 had come across approaching philosophical biology. 

 He thought of what Malthus had said regarding 

 the way disease, famine, and war keep down the 

 population of savage races to a much lower average 

 than that of civilised peoples ; he thought of the 

 similar ehmination that goes on in the animal 

 world, and it occurred to him to ask the question, 

 " Why do some die and some live ? " " And the 

 answer was, clearly, that on the whole the best 

 fitted live. From the efiects of disease the most 



* E.g. by Charles Wells, Patrick Matthew, James Cowles Prichard. 



