246 



The Unity of the Organism 



A Still Closer Description of the Suhrational Moiety of 



Psychic Life 



And this brings us to where our final return may be made 

 for purely descriptive and comparative purposes, to the 

 subrational moiety of psychic life, the purpose of the re- 

 turn tliis time being to characterize this moiety as faith- 

 fully but as briefly as possible on the basis of the total re- 

 sults of researches in the field up to the present time. So 

 bulky and varied are these results that to examine them 

 exhaustively is hardly possible for any one person even 

 though he be a specialist in the field. Much less possible is 

 it, then, for a general zoologist to make such an examina- 

 tion. Nevertheless it is, I believe, possible to give an 

 epitome of the present state of knowledge that shall be true 

 in all fundamental respects and liighly significant for our 

 enterprise. 



Remarks on the Classes of Suhrational Life 



In giving this epitome we shall not try to maintain a sharp 

 distinction between reflexes, whether of the tropistic or any 

 other type, and instincts. To begin with, as always, when 

 a large and intensively cultivated domain of science is en- 

 tered for the purpose of extracting from it its most certain 

 major results, we may take it for granted that the ex- 

 tremists touching any portion of the field over which di- 

 vergence is wide and warm, are unsafe guides for the gen- 

 eral student. Thus, the student who enters the realm of 

 animal behavior for such a purpose as that for which we 

 are now entering it soon sees that those specialists who find 

 nothing but tropisms, and these of the most uncompro- 

 mising sort, in the activities of much of the animal king- 

 dom, are not the ones to whose guidance he can entrust 



