EXHA US TIVENESS. 6 1 



characteristic differences between his work 

 and that of Lamarck and others, apart from 

 differences in the explanations offered, is its 

 superb exhaustiveness. It is as impossible 

 now to take the ideas of descent and of natural 

 selection out of the world as to take a star out 

 of the sky. The firm establishment of these 

 ideas was due to the quality and quantity of 

 Darwin's work, and both of these were deter- 

 mined by the same exhaustiveness in method. 



When he started out to describe the single 

 little abnormal cirriped from the west coast 

 of South America, he was characteristically 

 led, as he said, for the sake of comparison, to 

 examine the internal parts of as many genera 

 as he could procure. This untamed determina- 

 tion to find out all there was to know about 

 what he was describing was associated with a 

 fine contempt for the kind of work that merely 

 describes new things without showing all their 

 connections. One of the greatest and most 

 constant obstacles to his progress was that this 

 intellectual quality was so rare or so little cul- 

 tivated in other naturalists; so much of the 

 scientific material with which he had to deal 

 was so superficially or carelessly worked out 

 that he never knew what to trust. 



Among the best examples of this spirit of 



