PREFACE 



be possible until men of science generally 

 again take up the study of Plato and Aristotle, 

 or at least busy themselves, as did Agassiz, 

 with some comprehensive modern philosopher 

 like SchelHng. But it should not be very hard 

 for those who are engaged in the biological 

 sciences and those who are given to Hterary 

 pursuits to reahze that they are aUke inter- 

 ested in the manifestations of one and the same 

 thing, the principle of hfe. In Agassiz himself 

 the vitahty of his studies and the vitahty of the 

 man are easily identified. 



In conclusion I must thank the pubHshers, 

 Houghton Mifflin Company, for the use of 

 selections from the copyright books of Mrs. 

 Agassiz and Professor Shaler; these and all 

 other obhgations are, I trust, indicated in the 

 proper places by footnotes. I owe a special 

 debt of gratitude to Professor Burt G. Wilder 

 for his interest and help throughout. 



Lane Cooper 



Cornell University, 

 April 7, 1917. 



[vii] 



