444 HARVEY CAR I? 



customary stimulus, resulting in behavior of the trial and error 

 sort which finally leads to accidental relief. Or, needs may be 

 regarded as a constituent part of an animal's nature. On neither 

 hypothesis does the concept of need violate the enunciated prin- 

 ciple. Again, the specification of the names of a few of those 

 who do use the term in the tabooed sense would satisfy one of 

 the reviewer's needs. A suspicion is aroused that the author is 

 here strenuously belaboring a straw man of his own manufacture. 

 (2) The learning process is explained under two main laws 

 (effect and exercise) and two secondary laws (assimilation and 

 partial activity). In the main the reviewer sympathizes with 

 this formulation, but finds occasion for a few minor criticisms, 

 (a) I doubt their comprehensiveness. I am not ready to admit 

 that selection of acts according to their affective (pleasure-pain) 

 consequences is the only principle of selection. The law of exer- 

 cise is to some extent the application to animal acquisitions of 

 the secondary laws of association. The law of exercise is in- 

 adequate in the field of animal learning, just as the secondary 

 laws of association are inadequate to give a complete and com- 

 prehensive account of all the known conditions of human learn- 

 ing, e.g., the phenomenon of the influence of the temporal dis- 

 tribution of trials or effort. My feeling is that the gradual 

 selection and automatic growth of an act is too complex a 

 matter and too little understood at present in many of its phases 

 to be embraced adequately under the principles enunciated. 

 Learning is conceived in too simple a manner. On page 280 is 

 found the statement that the evolution of behavior is a simple 

 matter; it reduces to differences of concrete particular connec- 

 tions and to differences in learning ability. This may be true, 

 but I have found that the analysis of what constitutes degrees 

 of learning ability is anything but a simple matter, (b) The 

 law of effect states that in a series of random acts the selection 

 of the proper or teleological act is made on the basis of the 

 satisfying arid dissatisfying consequences of those acts. What 

 is satisfying or annoying can often be inferred on the basis of 

 analogy with the human, e.g., food or physical pain due to 

 electric shock. In case this method fails to give a clue, we 

 need some objective criteria. Satisfying conditions, we are 

 told, are those which the animal tends to attain and preserve, 

 and the annoying are those which are avoided and abandoned 



