here replace experience 29 



the one case are (1) the environment, and 

 (2) experience: the latter an essentially 

 positive or teleological factor, since it is 

 always directed towards self-conservation or 

 betterment. But the factors fundamental in 

 the other case are (l) natural selection, and 

 (2) amphimixis or the periodical blending of 

 two ancestral strands of the immortal germ- 

 substance; and both alike are non-teleo- 

 logical. 



Can it be that one and the same end can 

 be reached by such disparate means ? Its at- 

 tainment through experience without natural 

 selection is conceivable : its attainment with- 

 out experience, by natural selection and for- 

 tuitous variation alone, is surely inconceivable. 

 That both experience and natural selection 

 have co-operated seems indeed to be the fact, 

 as Darwin himself at all events assumed. But 

 this co-operation Weismann with Wallace 



