150 SUPER-ORGANIC EVOLUTION 



of domestic plants and animals, and after a time 

 I perceived perfectly that the most important 

 modifying influence lies in the free choice open 

 to man in selecting individuals for the propagation 

 of species. 



" Having often studied the mode of life and 

 habits of animals, I was prepared to form a just 

 idea of the struggle for life, being acquainted 

 already, from my geological studies, with the 

 vastness of bygone periods. 



"Having read, therefore, by a happy chance, 

 Malthus's work, The Principle of Population, I 

 conceived the idea of natural selection." * 



The title struggle for life is suggested by 

 Malthus's theory of the law according to which 

 aliments increase in arithmetical and animals in 

 geometrical progression, and therefore a great 

 number of those born are destined to die from 

 want of nourishment. This law, however, offers 

 great contradictions. 2 



Natural selection in the theory of evolution is an 

 incentive that facilitates the predominance of this 

 or that form, and the means of securing the victory 

 to the most suitable, and, in the last resort, is a 

 mechanical problem, for of two or more systems of 

 conflicting forces the more powerful must prevail. 



1 E. Haeckel, Hist, de la Creation naturelle, p. 119. 



2 Ibid., p. 144. 



