NERVOUS AND ENDOCRINE CONTROL I 39 



pared. The results revealed no important differences in the learning proc- 

 esses of the two groups, while in speed of learning the rats had somewhat 

 the best of it. Of course maze-Jearning presents a problem of a very simple 

 sort, with a solution dependent on trial and error and the establishment 

 of habits through repetition. There is no need to establish complicated 

 reactions. 



Perhaps the most interesting experiments in animal learning which have 

 been made to date are those being carried on at the time of this writing by 

 Dr. Wolfe at the Institute of Human Relations at Yale University. Dr. 

 Wolfe has been experimenting with young chimpanzees, using slot- 

 machines which have been dubbed "chimpomats." By the insertion of 

 poker chips, the chimpanzees get food. The chimpanzees have learned 

 not only to insert chips, but to distinguish between chips of different sizes 

 and colors, using each type of chip in the proper machine and inserting 

 two chips where two were required. They learned the process first by 

 imitating their human instructor and then by imitating one another. 

 They have established associations between the chips and food which 

 are so strong that they will work as hard to get the chips as to get the food 

 itself. When chips are scattered among them in their living quarters, where 

 there are no "chimpomats," they will select those which are of value and 

 keep them until they are taken to the room where the "chimpomats" are. 

 The stronger will also take chips from the weaker in very human fashion. 



It is safe to say, that is, there are differences in the learning processes of 

 men and animals; these differences are quantitative rather than qualitative. 

 Men may learn more or learn more readily, but they learn in the same 

 way. It is in the solving of problems, where the individual has had no 

 opportunity for learning, that the mental superiority of human beings is 

 most evident, so let us see whether there are any fundamental differences 

 in the human and animal thinking processes. 



It has been held that the superior performance of men in solving new 

 problems is due to their having imagination and reason, qualities which 

 animals lack. Recent experiments make this appear improbable. Imagina- 

 tion is the ability to picture in the mind situations which are not present. 

 Reason is the abihty to solve problems without going through a physical 

 process of trial and error. Reason would be impossible without imagina- 

 tion, for in reasoning the situation has to be comprehended and the results 

 of certain actions have to be foreseen. The trials are made and the errors 

 eliminated in the fn'md. If we study human and animal behavior from the 

 same objective standpoint, it seems certain that if we allow these qualities 

 to men we must allow them to animals as well. 



When the young chimpanzees pick up the chips scattered in a room 

 where there are no "chimpomats," selecting those which are usable in 

 the machines and discarding those which are not, they show imagination. 

 They must have some sort of mental image of the machines and of the 



