190 EVOLUTION 



the influence of a changeful environment, 

 both in modifying and in eliminating. But 

 he had another deep idea, which Goethe 

 shared, of an inherent formative impulse in 

 the creature. "In every living being there 

 exists a capability of an endless variety of 

 form-assumption; each possesses the power to 

 adapt its organization to the changes of the 

 outer world, and it is this power, put into 

 action by the change of the universe, that 

 has raised the simple zoophytes of the primi- 

 tive world to continually higher stages of 

 organization, and has introduced a count- 

 less variety of species into animate Nature." 



But it is in Goethe that we find the fullest 

 expression of the idea of the innate tendency 

 of a living creature to fuller self-realization. 

 At the same time he held with Lamarck that 

 "the way of life powerfully reacts upon all 

 form," and with Buffon that the orderly 

 growth of form "yields to change from ex- 

 ternally acting causes." 



The main idea of Goethe, of an inherent 

 growth force, has constantly reappeared, 

 notably among the American palaeontolo- 

 gists: witness Cope's "bathmism"; and 

 now among the whole rising generation of 

 vitalists, German and other. The anatomist 

 and systematist, the chemical and physical 

 physiologist, have been, and still are, wont 



