REMARKS ON NATURAL SELECTION. 347 



If, on the other hand, Mr. Darwin maintains natural 

 selection to be a cause of variation, this comes to say- 

 ing that when an animal has varied in an advantageous 

 direction, the fact of its subsequently surviving in the 

 struggle for existence is the cause of its having varied 

 in the advantageous direction or more simply still 

 that the fact of its having varied is the cause of its 

 having varied. 



And this is what we have already seen Mr. Darwin 

 actually to say, in a passage quoted near the beginning 

 of this present book. When writing of the eye he says, 

 " Variation will cause the slight alterations ; "* but the 

 "slight alterations" are the variations; so that Mr. 

 Darwin's words come to this that " variation will 

 cause the variations." 



There does not seem any better way out of this 

 dilemma than that which Mr. Darwin has adopted 

 namely, to hold out natural selection as " a means " of 

 modification, and thenceforward to treat it as an 

 efficient cause ; but at the same time to protest again 

 and again that it is not a cause. Accordingly he 

 writes that " Natural Selection acts only by the preser- 

 vation and accumulation of small inherited modifica- 

 tions," t that is to say, it has had no share in inducing 

 or causing these modifications. Again, " What applies 

 to one animal will apply throughout all time to all 

 animals that is, if they vary, for otherwise natural 

 selection can effect nothing " | ; and again, " for natural 

 selection only takes advantage of such variations as 



* ' Origin of Species,' p. 146. t IMd. P- 75. 



J Ibid. p. 88. 



