Preface 



Xlll 



All who knew him will keep in memory a person- 

 ality alive and young to a rare degree, fulfilling 

 itself in a passion for music, much laughter, a per- 

 fectly disinterested love of truth, a delight in pro- 

 ducing delight in others, and the keenest possible 

 interest in life itself whichever way it led him. 



During the spring and early summer of 1915 

 my brother was at work upon a book for publica- 

 tion by Messrs. Cassell in the autumn. In May he 

 writes to M. Bergson, " I am hard at work on my 

 book about evolution. I think I am going to call 

 it ' An Introduction to Biology ' — Biology as I think 

 it ought to be, not Biology as it is. For the problem 

 of evolution is merely a department of the problem 

 of life, it appears to me. I am convinced that 

 the theory of natural selection is in no sense an 

 explanation of evolution." 



The plan of the book is sketched in a prospectus 

 written for the Publishers in June, 1915. 



" An Introduction to a Biology 



" This book is addressed to all those who are 

 curious about the meaning of life, and is an attempt 

 to put before them the essence of the current 

 mechanistic explanation of the organism and mate- 

 rialistic explanation of the universe, in order that 

 they may examine for themselves these accepted 

 scientific explanations of life. The author does not 

 pretend to set forth a series of conclusions led up 

 to by the stages of a logical argument which follow 

 inevitably and relentlessly from one another, and 



