34 HISTOKICAL 



It is well known that before Darwin and Wallace turned their 

 attention to the subject, the origin of organisms by evolution as 

 opposed to origin by separate acts of creation had often been 

 suggested. There was already at the beginning of the nineteenth 

 century a considerable accumulation of facts regarding the 

 structure and relation of organisms to one another and regarding 

 the fossil remains of organisms. This evidence was seen to point 

 to evolution as against creation, but until Darwin and Wallace 

 produced their theories no one had been able to formulate a satis- 

 factory hypothesis as to how evolution could have come about. 

 It is of great interest to observe that it was after reading Malthus 

 that both Darwin and Wallace independently formulated their 

 theories. Malthus had, in fact, when taking up for consideration 

 the quantitative aspect of the problem, so far as man was con- 

 cerned, been dealing with that class of facts upon which, not only 

 the quantitative, but also the qualitative aspect of the problem 

 is based. When Darwin and Wallace, with the problem of evolu- 

 tion before them", which is essentially the problem of quality 

 the problem of the manner in which one type of organic form can 

 be derived from another type chanced to read Malthus, their 

 attention was called to the class of facts connected with the birth- 

 rate, the death-rate, and allied phenomena. They realized that 

 among species in a state of nature a somewhat similar state of 

 things existed to that which Malthus, with another aspect of the 

 problem in view, was investigating in the case of man, and from 

 a consideration of these facts they founded independently the 

 hypothesis of natural selection. 



It is of interest to note what Darwin and Wallace themselves 

 say as to their indebtedness to Malthus. In a passage in the well- 

 known autobiographical sketch Darwin writes as follows : ' in 

 October 1838, that is fifteen months after I had begun my systema- 

 tic inquiry, I happened to read for amusement Malthus' ' Popu- 

 lation ', and being well prepared to appreciate the struggle for 

 existence which everywhere goes on from long-continued observa- 

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

 hold of a theory by which to work.' J In two letters that have 



1 Life and Letters of Charles Darwin, vol. i, p. 83, 



