EXPLANATION OF OBSERVATIONS 155 



ter of fact, my own introspection convinced me that the 

 third and fourth cases were surely, and the first and 

 sixth were very probably, due to insufficient concentra- 

 tion on the part of the questioner. Accordingly there is 

 everywhere in these cases a difference of + i or -|- 2 be- 

 tween the number thought of and the number tapped 

 (see page 92 f.). The data in the second and fifth 

 and still more in the seventh case were too meager to 

 warrant an attempt at explanation, for it is not even 

 known whether Hans responded with more or fewer taps 

 than was expected by the questioner. It is unfortunate 

 that a more complete record was not made. 



The frequent and intentional attempts of Mr. von . 

 Osten to induce the horse to give an incorrect response, 

 — which, by-the-way, were regularly unsuccessful — ^be- 

 long only apparently to this group. Thus he asked, e. g., 

 " 2 times 2 is 5, is it not? " " 3 times 3 is 8? ", etc., but 

 Hans refused to be misled, and responded correctly. 

 This was from the very beginning one of the main argu- 

 ments for independent thinking on the part of the horse. 

 The actual procedure was as follows, even though the 

 questioner had said " 2 times 2 is 5 '', there still was pres- 

 ent in his consciousness the number 4. I, myself, would 

 think either of the first member of the equation, i. e., 2 

 times 2, in which case Hans would respond with 4 taps or 

 I would have in mind the second member, i. e., 5, in 

 which case he would respond with 5 taps. Never did I 

 succeed ii? thinking of both at the same time. The associ- 

 ation between the thought " 2 times 2 " and the concept 

 "4" is so close and supported by so many other associ- 

 ations that the attempt to form a new one, that is at com- 

 plete variance with all these, is futile. One may say 

 " 2 times 2 equals 5 " but it is impossible to conceive it. 



