THE PATH OF EVOLUTION 



explicable phenomena in organic life, up to and in- 

 cluding that of man, find only here their satisfactory 

 explanation. 



In the doctrine of Natural Selection and Survival 

 of the Fittest, the variations from inheritance that 

 benefit the individual or its descendant are often pro- 

 duced by unconscious response to external conditions 

 in the environment, sometimes too obscure to be 

 recognized, and constitute then what are commonly 

 called accidental changes, but in reality they are the 

 result of established laws, only so deeply involved 

 that they are not apparent to us. 



In the case of sexual selection a new motive force 

 is supplied. It necessarily requires conscious action 

 and volition. These phenomena in the higher order 

 of life are assumed to be present and efficient. 



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