ANIMAL CONSCIOUSNESS 19 



port, he communicated the fact by a shake of the head. 

 We were told that the questioner had to confine himself 

 to a certain vocabulary, but this was comparatively rich 

 and the horse widened its scope daily without special 

 instruction, but by simple contact with his environment. 

 His master, to be sure, was usually present whenever 

 questions were put to the horse by others, but in the 

 course of time, he gradually responded to a greater and 

 greater number of persons. Even though Hans did not 

 appear as willing and reliable in the case of strangers 

 as in the case of his own master, this might easily be 

 explained by the lack of authoritativeness on their part 

 and of affection on the part of Hans, who for the last 

 four years had had intercourse only with his master. 



Our intelligent horse was unable to speak, to be sure. 

 His chief mode of expression was tapping with his right 

 forefoot. A good deal was also expressed by means of 

 movements of the head. Thus " yes " was expressed by 

 a nod, " no " by a deliberate movement from side to 

 side; and "upward," "upper," "downward," "right," 

 " left," were indicated by turning the head in these di- 

 rections. In this he showed an astonishing ability to 

 put himself in the place of his visitors. Upon being 

 asked which arm was raised by a certain gentleman op- 

 posite him, Hans promptly answered by a movement to 

 the right, even though seen from his own side, it would 

 appear to be the left. Hans would also walk toward the 

 persons or things that he was asked to point out, and he 

 would bring from a row of colored cloths, the piece of the 

 particular color demanded. Taking into account his 

 limited means of expression, his master had translated a 

 large number of concepts into numbers ; e. g. : — the letters 

 of the alphabet, the tones of the scale, and the names of 



