EXPLANATION OF OBSERVATIONS 179 



other, each gazing steadfastly at the other. Mr. Kretch- 

 mer was convinced, however, that the dog was not 

 guided by any sort of sign, but rather by suggestion. 

 He based his belief on the following two observations. 

 After some practice, he says, the tests were also success- 

 ful when he did not look at the dog, but stood back to 

 back with it, or when he screened himself from the dog's 

 view by stepping to one side behind a curtain. The 

 tests were unsuccessful, on the other hand, whenever he 

 was mentally fatigued or had taken some alcoholic drink. . 

 The arguments do not appear to me to be adequate. If 

 he turned his back upon the dog and no other observer 

 was present, he had no means of knowing whether the 

 dog did not, after all, peer around to get a peep at him. 

 If others who knew the desired number, were present, 

 the dog might have gotten his cues from them. And 

 there may be some doubt whether the curtain adequately 

 served the purpose for which it was intended. At any 

 rate, it was added that all attempts to influence the dog 

 from an adjoining room — which would thus exclude 

 effectively all visual signs — were utter failures. I am 

 also strengthened rather than weakened in my belief, by 

 the second argument which Mr. Kretschmer makes, viz. ; 

 that mental fatigue or the use of alcohol on the part of 

 the questioner tends to make the result unsatisfactory. 

 We noted a similar effect in the case of the horse (page 

 150), where a disturbance of the " rapport " between the 

 questioner and the horse was invoked by some by way of 

 explantion. The facts were explained by us much more 

 simply. We attributed the result to the close correlation 

 between the type of mental concentration and the nature 

 of the expressive movements — ^ correlation which we 

 have shown experimentally to exist. I cannot, therefore. 



