698 



SCIENCE 



[N. S. Vol. XXVII. No. 696 



DISCUSSION AND CORRESPONDENCE 



THE IIn'TERPRETATION OF THE BEHAVIOR OF THE 



LOWER ORGANISMS 



In my recent volume on the " Behavior of 

 the Lower Organisms " are set forth certain 

 views which have called forth discussion and 

 criticism.' In response to many questions 

 which indicate that there is a general interest 

 in the subject, I wish here to reexamine some 

 of the matters raised. 



Objections have centered about my discus- 

 sion of certain general theories of behavior, 

 particularly of the tropism theory, and of cer- 

 tain applications of the theory of selection. 

 Some of the criticisms are clearly just; others' 

 Beem to me to rest upon misunderstanding, 

 while still others show actual differences of 

 opinion. To set in a clear light these different 

 categories is my present wish. 



The only question of importance is : How far 

 is there a real difference of opinion, among 

 workers familiar at first hand with the phe- 

 nomena, in regard to (1) the actual, experi- 

 mental facts of behavior, (2) the general and 

 important laws or principles underlying these 

 facts. Divergences due to different lines of 

 interest, different fields of investigation and 

 different understanding of terms merely ob- 

 scure the essential point and need to be cleared 

 away. To make clear the objects and meaning 

 of different investigators sometimes reveals 

 harmonious diversity in place of conflict ; when 

 this result is not reached, it at least shows pre- 

 cisely where opposition lies, and suggests ex- 

 perimentation that shall turn opposition into 

 agreement. 



It will greatly facilitate the attainment 

 of these ends if I first set forth briefly certain 

 purposes and principles that guided me in the 

 preparation of my account. 



1. My book was designed mainly as a topo- 

 graphic survey of the field of behavior in the 

 lowest organisms. My primary purpose was 

 to give the reader a clear idea of the ob- 



* See especially Torrey, in Science, September 

 0, 1907; Loeb, The Journal of Experimental Zool- 

 ogtfi Vol. 4, No. 1, 1907, and Pflilger's Archiv, 

 Bd. 115, 1906, p. 580; Parker, Science, October 

 25, 1S07. 



servable facts, so that he might gain somewhat 

 the same impression that he would from see- 

 ing the phenomena themselves. To aid in 

 this, I characterized as typical such phenomena 

 as were fairly representative of the behavior in 

 general, while phenomena that were rare or 

 unique, like the reaction to the electric current, 

 I said were not typical and gave an inadequate 

 idea of the nature of behavior. This, while 

 strictly true, has led to misunderstanding; 

 certain critics have assumed that I considered 

 such phenomena as of no importance from any 

 point of view. I believe that there is nothing 

 in my treatment that gives ground for this 

 assumption. Special cases of this form of 

 criticism will come up in later paragraphs. 



2. The most important characteristics of be- 

 havior have always seemed to me those shown 

 in the biological interrelations of the physio- 

 logical processes : in the relations of behavior 

 to preserving the organism, to supplying the 

 requirements for metabolism, and in general to 

 keeping the other physiological processes in 

 progress. These adaptive or regulatory char- 

 acteristics of behavior furnished the problem to 

 the solution of which attention was in my 

 book mainly directed. Therefore I character- 

 ized as " important," " significant," and the 

 like, mainly those features of behavior which 

 seemed to lead toward an understanding of its 

 regulatory character. Other investigators, not 

 having this problem in the center of interest, 

 have considered quite other matters as the im- 

 portant ones. Thus Torrey (I. c.) holds that 

 we find the most important features of be- 

 havior in precisely those features that are not 

 regulatory. Judgments of importance are of 

 course relative; importance for what? is the 

 question. I take it that the question in which 

 Torrey is primarily interested is that regard- 

 ing the nature of the immediate change which 

 occurs in living matter when an external stim- 

 ulus acts upon it. 



3. We now come more directly to the con- 

 tent of the work. Tears of investigation had 

 convinced me that the complexity of the prob- 

 lems of behavior had been underestimated; 

 that even in the lower organisms we are com- 

 pelled to deal with an immense number of 



