188 The Unity of the Organism 



consequently, hold a large place in our effort to see what Loeb 

 as a representative of the elementalist school in biology is 

 able to do with the integrative action of the nervous system. 

 Let it be understood that with the general controversy 

 which has gone on so long and warmly concerning the value 

 of the tropism theory for explaining animal behavior, we are 

 little if at all concerned in this discussion. The point of 

 cardinal importance for us, and the thing about the theory 

 which, as mentioned above, Loeb and his followers seem not 

 to have perceived clearly, is the fact that the theory is 

 really dependent for so much of validity as it has on the 

 conception of the organism as a whole. In other words, the 

 theory is in essence an organismal and not an elementalistic 

 theory. Hence it results that since Loeb is the author and 

 chief proponent of the tropism theory, but is at the same 

 time an extreme elementalist, his general position as an in- 

 terpreter of animal activities and the nervous system con- 

 tains fundamental contradictions. Indicating these con- 

 tradictions and exploring, though incompletely, the course 

 along which the truth lies, will form a natural conclusion to 

 our study of the integrative office of the nervous system. 



The Organismal Character of Tropisms Partly Recognized 



By Loeb 



I first call attention to the fact that Loeb himself has seen, 

 though "as in a glass darkly," the organismal character of 

 the tropism theory. Speaking of the lack of a sharp boun- 

 dary between reflexes and instincts, he says some authors 

 are wont to speak of reflexes when the responses to stimuli 

 pertain to single parts or organs, but they "speak of in- 

 stincts where the reactions of the animal as a whole are 

 involved (as is the case in tropisms)." 



And the same idea comes out still more definitely in a 

 proposal to discard the term reflex as applied to such a re- 



