334 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1921. 



marck, Lyell, and Darwin are the four greatest scientists who devoted 

 themselves to this research) ends by being proclaimed by a philoso- 

 pher as, so to speak, a logical necessity. 



As the present short outline of the historical development of the 

 idea of evolution shows, this idea has been established much more 

 by scientific research than by philosophic speculation. And while 

 the inorganic evolution was recognized by some of the Greek 

 philosophers and by Descartes and Kant, the idea of organic evolu- 

 tion was never an integral part of any of the great systems of 

 philosophy, and no great philosopher before Darwin had recognized 

 the general and universal bearing of the idea of evolution. It is a 

 rather extraordinary fact that an idea of an eminently philosophic 

 importance, such as the idea of universal evolution, should never have 

 been recognized as such until after science had demonstrated it — 

 this is a bit humiliating to philosophers ; and it shows us that human 

 knowledge, if it wishes to attain its total unity, must find its support 

 and its inspiration as much in scientific research as in pure specula- 

 tion. 



