554 



PHILOSOPHICAL THOUGHT. 



Development.^ And he was further probably quite as 

 deficient as Schelling and his followers in recognising 

 the role which the exact or mathematical methods were 

 destined one day to play also in the historical sciences 

 of nature. 



If, in the light of our present knowledge, we read 

 afresh the writings of such thinkers as Kielmeyer, 

 Schelling, Steffens, Oken, and others, to which we may 

 add the names of Lamarck and Geoffroy, of Treviranus 

 and Von Baer, we meet with almost all the leading ideas 

 which governed natural science at the end of the century 

 except one, and that is, if I may say so, a mathematical 

 or arithmetical conception.^ This idea, nevertheless, was 

 put forward about the same time in this country by 

 Malthus in his ' Essay on Population.' It refers to the 

 disproportionate increase of all organisms if compared 

 with their means of subsistence : it is the phenomenon 

 of overcrowding which, combined with that of " varia- 

 tion," necessitates an automatic " selection " leading to 

 the " struggle for existence " and the " survival of the 

 fittest." But it was not till forty years after this period 

 Afterwards that the reflections contained in Malthus's ' Essay ' met 



taken up 



by Darwin, in the mind of Darwin with the necessary conditions by 



11. 



An omitted 

 idea : Mal- 

 thus. 



12. 



^ This, however, with the quali- 

 fications contained in Lotze's and 

 Wundt's criticisms of this school : 

 see supra, pp. 549, 550. 



'^ Since I wrote this passage, in 

 the first years of the present cen- 

 tury, a second important concep- 

 tion has been added, of which we 

 find no trace among the naturalists 

 and philosophers I am here dealing 

 with, but which has likewise tended 

 in the direction of introducing math- 



ematical or arithmetical methods 

 into the study of the living creation. 

 This is the conception anticipated 

 already by Francis Galton and ren- 

 dered more precise by the accept- 

 ance of Mendel's theories, which 

 had been neglected and forgotten. 

 Though published far back in the 

 nineteenth century (1865), they do 

 not belong to the history of Thought 

 during that period. 



