Preface xv 



be no question that it is a truth) not received more atten- 

 tion from modern behavior specialists? There are probably 

 several reasons, but a particularly influential one seems to be 

 the fact that the very purpose, and the method of ex})erinu'ii- 

 tation involving the idea of control by the student are 

 such as to encourage overlooking the plienomena, and to 

 obscure their significance even if they are noticed. 



Unorthodoxly enough from the standpoint of })resent 

 school psychology, my entrance into this realm was from 

 the side of the nature and the theory of knowledge. And so 

 far as my explorations in the realm have gone, two men, 

 Aristotle and the late Professor G. H. Howison have influ- 

 enced me so vitally that I must say a few words on the 

 subject. • 



For many years Aristotle was two distinct persons to me, 

 so far as any real influence upon my thinking was con- 

 cerned. On the one hand there was Aristotle the metaphysi- 

 cian to whom I had been formally introduced by Howison in 

 a private outside-of-hours University course (which with 

 great generosity he had given me), the medium of the in- 

 troduction being the De Anima. On the other hand was 

 Aristotle the zoologist, acquaintance with whom was at first 

 picked up in the usual naturalist fashion, but wliich had 

 later ripened into intimac}^ as I like to characterize it, by 

 our common interest in marine zoology, his good description 

 of the anatomy of a tunicate being a special passport to my 

 affection. It would hardly be an exaggeration to say that 

 all my philosophizing in biology has aimed at fusing tliese 

 two Aristotles into one. I do not mean that this has been 

 my conscious and express aim. It has been so only instinc- 

 tively, or intuitively, or "at heart," or by "working hy- 

 pothesis," or by whatever expression one chooses for it. 

 And here comes the part played by Professor Howison : As 

 I take a bird's eye view now of what is set forth in this and 

 other general writings of mine, and contemplate the whole in 



