Laws and Hypotheses for Behavior 267 



in the laws of exercise and effect. Jennings has formulated 

 as an adequate account of learning the law that : ' When 

 a certain physiological state has been resolved, through 

 the continued action of an external agent, or otherwise, 

 into a second physiological state, this resolution becomes 

 easier, so that in course of time it takes place quickly and 

 spontaneously" ('Behavior of the Lower Organisms/ p. 289). 

 "The law may be expressed briefly as follows:- - The 

 resolution of one physiological state into another becomes 

 easier and more rapid after it has taken place a number of 

 times. Hence the behavior primarily characteristic for 

 the second state comes to follow immediately upon the first 

 state. The operations of this law are, of course, seen on 

 a vast scale in higher organisms in the phenomena which 

 we commonly call memory, association, habit formation 

 and learning ' (ibid., p. 291). This law may be expressed 

 conveniently as a tendency of a series of states 



A->B->C->D 

 to become A -> D 



or A -> B 1 -> C 1 - D 



B 1 and C 1 being states B and C passed rapidly and in a 

 modified way so that they do not result in a reaction but 

 are resolved directly into D. 



If Professor Jennings had applied to this law the same 

 rigorous analysis which he has so successfully employed 

 elsewhere, he would have found that it could be potent 

 to cause learning only if supplemented by the law of effect 

 and then only for a fraction of learning. 



For, the situations being the same, the state A cannot 

 produce, at one time, now B and, at another time, abbrevi- 

 ated, rudimentary B 1 instead of B. If A with S produces B 

 once, it must always. If D or a rudimentary B 1 is produced, 

 there must be something other than A ; A must itself have 



