REWARD AND PUNISHMENT IN HABIT FORMATION 273 



are suggestive and are doubtless of importance in the explanation 

 of the learning process, the writer is unable to give a satis- 

 factory interpretation of this experiment on the basis of one or 

 all of these principles. 



The seeming simplicity of the mechanical principles of a simple 

 type of learning grows into complexity when one attempts to 

 account for habit formation under different conditions. The 

 writer does not hope to give a set of principles which will explain 

 the mechanics of all types of habit formation, nor does he care 

 to add another guess as to the physiological changes which take 

 place, but desires some kind of interpretation for the results 

 obtained in the above experiments. Any part or even all of the 

 principles which have been mentioned do not give a satisfactory 

 explanation of the facts. There are at least two other factors 

 which seem of importance. 



Native tendencies. Something of the importance of the native 

 tendencies of the organism in the learning process has been 

 recognized in a very general way by a number of students of 

 behavior, but the writer here refers to specific tendencies. The 

 specific native tendency with which the learning process is linked 

 seems of vital importance in determining the length of time for 

 perfecting any habit. Subjects trained with the most favorable 

 strength of electric shock perfected the same habit in slightly 

 over half the time that subjects trained with the most favorable 

 degree of hunger. Most probably this is due not to a difference 

 in the values of pleasant and unpleasant stimuli but to the fact 

 that in one case the process is tied-up with the tendency of flight 

 and in the other it is tied-up with the food seeking tendency. 

 The tendency of flight is a very strong tendency and takes pre- 

 dominance over the food seeking tendency when both are stim- 

 ulated. The rat which is seeking food, on the approach of an 

 enemy takes to flight and ceases the search of food for the time 

 being. Were these comparisons between sex and flight tend- 

 encies the results might be very different. The stronger the 

 pull or drive of the tendency with which an act is linked-up the 

 less likely is the individual to be attracted from the performance 

 of the act. The subject which is very hungiy is seldom inter- 



