EFFECT OF LENGTH OF BLIND ALLEYS ON MAZE LEARNING 53 



the animal goes forward or back on emerging from a blind 

 alley. In this respect, however, as in many others, there are 

 rather large individual differences. From the very first ex- 

 perience in the maze, and this makes the test of the probability 

 law rather difficult, the learning factors enter in and rapidly 

 decrease the returns in favor of the general forward orientation. 



6. It has been found desirable in work of this kind to study 

 individual reactions in detail. Mere averages do not show the 

 significant aspects of the behavior in many cases. A detailed 

 report of individual " choices " in the maze, by a method which 

 promises to be fruitful, is being prepared to justify further the 

 statement in the present paper regarding the inadequacy of 

 frequency and recency laws as explanations of the rat's maze- 

 learning. 



7. Responses to stimuli cannot take place instantaneously, 

 neither do stimulation effects fade away momentarily. Besides 

 this, response tendencies and muscular strains, maintained for 

 a shorter or longer time, constantly set up new sensory impulses 

 (proprio-ceptive stimuli) which again stimulate reactions. It 

 is suggested that by such means as these, and possibly by others 

 not yet known, the effects of successive stimuli, such as an 

 animal encounters in getting through a problem box to food, 

 operate in a measure simultaneously, and the resulting response 

 is on the whole the most consistent or complete one under the 

 whole .circumstance. The channels to this most complete 

 response are gradually forced most open or permeable; their 

 greater consistency of operation (facilitation) brings about an 

 intensity of activity through them which in repeated trials 

 gradually short-circviits through the infinitely numerous path- 

 ways involved and thus brings about the gradual elimination 

 of useless random acts. It is suggested that learning comes 

 about by this means. It is hoped that this suggestion may be 

 fruitful toward an understanding of how a final success can 

 operate back (as it appears externally to do) upon the random 

 acts leading to it so as gradually to bring about their elimination. 

 This is the theory which the writer has called the " completeness 

 of response " principle in learning, and it seems to him to account 

 for the results obtained in the present experiment as well as for 

 others which have been uncritically attributed to the stamping-in 

 effects of pleasantness. 



