INTRODUCTION 7 



tentionally in the training of horses, could not have oc- 

 curred even as unintended signs, for otherwise Mr. 

 Busch would have detected them. And in order to be 

 observed by him it was immaterial whether they were 

 given purposely or not. The same signs, therefore, 

 which as a result of his observations were declared not to 

 be present, could not be assumed to be involved as un- 

 intentional. 



For my part I am ready to confess that at this time I 

 did not expect to find the involuntary signals, if any such 

 were involved, in the form of movements. I had in mind 

 rather some sort of nasal whisper such as had been in- 

 voked by the Danish psychologist A. Lehmann, in order 

 to explain certain cases of so-called telepathy. I could 

 not believe that a horse could perceive movements which 

 escaped the sharp eyes of the circus-manager. To be 

 sure, extremely slight movements may still be perceived 

 after objects at rest have become imperceptible. But one 

 would hardly expect this feat on the part of an animal, 

 who was so deficient in keenness of vision, as we have 

 been led, by those of presumably expert knowledge, to 

 believe of the horse, — one would expect it all the less 

 because Mr. von Osten and Mr. Schillings would move 

 hither and thither in most irregular fashion while the 

 horse was going through his tapping, and would there- 

 fore make the perception of minute movements all the 

 more difficult. 



Nor was there anything in the exhibitions given at the 

 same time in a Berlin vaudeville by the mare " Rosa," 

 whieh might have shattered this belief. For, in the case 

 of f.iis rival of Hans, the movements involved were com- 

 paijwtively coarse. The closing signal consisted in bend- 

 ing forward on the part of the one exhibiting the mare, 



