412 SCIENTIFIC THOUGHT. 



how it dealt with final causes, with the apparent exist- 

 ence of a purpose, an end in the processes of nature, 

 notably of the living organism. 



It must here be remembered that the question how 

 living things come to exhibit traces of design and pur- 

 pose has really nothing to do with the nature and pro- 

 cesses of life : it is not necessarily a biological question. 

 Every machine shows the same marks of design, but is 

 not therefore alive. The influence of Darwin's principle 

 of natural selection, of overcrowding and consequent 

 struggle for existence and survival of the fittest speci- 

 mens, has therefore not been in the direction of explain- 

 ing any of the vital processes which are at work in the 

 individual organism. It is at best merely a statistical 

 relation, a peculiar phenomenon occurring only in a large 

 or congested group of living and self-multiplying beings : 

 it presupposes the facts of reproduction, heredity, and 

 variation ; it does not explain them. Hence I dealt 

 with Darwin's ideas in the last chapter, and did not 

 introduce them under the present heading of Biological 

 Thought. As we shall see later on, Darwin did re- 

 cognise the necessity of attempting also a biological 

 explanation. 



The possibility of explaining the marks of design as 

 merely apparent depends on the conception of the genetic 

 process acting on a large, a gigantic scale : individual 

 things put forth ever new developments by which they 

 eventually overtop their neighbours, ultimately advanc- 

 ing to such a degree of excellence and individual per- 

 fection that to an outside beholder the few surviving 

 specimens give the impression of having been origin- 



