310 Journal of Comparative Xcurology and PsycJwlogy. 



a deep-seated instinct.' Those experiments in which the time 

 element (the interval between stimulus and response) is of im- 

 portance should not be foreign to the natural tendencies; all 

 innate proclivities should be seized upon and, so far as possible, 

 should be utilized. The stimuli depended upon with the guinea 

 pig were hunger and desire for company. The former, since it 

 could be carefully controlled and kept a constant factor, was 

 used almost entirely. 



It was found that problems whose solution involved activ- 

 ity were solved most readily, while those which involved inge- 

 nuity were not solved at all. By ingenuity is meant a very 

 simple process, the putting of two and two together. A paw 

 or a nose may be used to attain an object when other methods 

 have failed. Within narrow limits the guinea pig is very active, 

 many of his movements being made at random. It can select 

 a few movements which have been successful and omit those 

 which have not, so that a path is learned merely by a proper 

 direction of activity. But there is no adaptation of movement 

 to a complication in the problem offered which would involve 

 even a simple new coordination. The absence of all power of 

 adaptation is the absence of all ingenuity. 



The guinea pig is a grazing animal, as has been mentioned ; 

 it neither digs nor climbs for its food, but runs about. It 

 scarcely ever pulls or pushes obstacles violently, and its gnaw- 

 ing is not adapted to getting into a box. A guinea pig will 

 gnaw for five minutes at a freely swinging door without happening 

 to give it a hard enough push to open it. The gentle swinging 

 of the door back and forth seemed to suggest nothing. All at- 

 tempts made thus far to give problems similar to those solved 

 by cats and dogs (by Thorndike, Hobhouse and others) were 

 unsuccessful, in the case of the adult as well as the young. 



Even though extremely hungry the little fellow will get dis- 

 couraged after finding that all the methods he knows fail to reach 

 the food, and he will sit down in a corner of the cage and re- 

 main there. At^ one time I left my brightest guinea pig six 



' Yerkes and HrcGiXS. Habit Formation in tlie Crawhsli. Hanard 

 Psychological Studies, Vol. I, 1902. 



