REACTION OF THE HORSE 221 



ping more carefully. From the slight inclination of the 

 master's body the horse would get the cue that he was ex- 

 pected to tap for a short time only, by the greater de- 

 gree of inclination he would know that he was to tap for 

 a longer period. In the second case he tapped rapidly 

 and did not raise his foot as high from the ground — 

 evincing a regard for the saving of energy, which may 

 well be attributed to a horse. And thus arose the con- 

 nection between the degree of inclination of the in- 

 structor's body and the horse's rate of tapping. 



So, now that the ability to count and solve problems 

 had become fixed — as the old gentleman thought — ^he be- 

 gan to instruct the horse in other branches. Since every- 

 thing had been translated into terms which were to be 

 expressed by means of tapping with the foot, and thus 

 really put into terms of number — which was perhaps 

 natural for an old teacher of mathematics — the same 

 mechanism was involved in these accomplishments as in 

 those of counting, etc. Mr. von Osten saw the animal's 

 intelligence steadily increase, without having the slightest 

 notion that between his words and the responsive move- 

 ments of the horse, there were interpolated his own un- 

 conscious movements — and that thus instead of the much 

 desired intellectual feats on the part of the horse, there 

 was merely a motor reaction to a purely sensory stimulus. 

 It has been a common custom of man to posit some ex- 

 traneous cause for movements resulting from certain in- 

 voluntary motions of his own, of which he is not aware, 

 (witness the divining-rod).* And furthermore, when 



* G. Franzius," privy counselor of the admiralty, master of the dry- 

 dock at Kiel, is responsible for the undeserved revival of the ancient 

 belief, long buried by science, that the divining branch is put into motion 

 solely as the result of the influence of hidden springs or treasures, and 



