ANIMAL PSYCHOLOGY 143 



characters or the Weather Bureau signals or any other markings, and 

 whether these markings have any meaning, is as wholly indifferent to 

 the horse as it is unnecessary for him to go through any reasoning 

 process in order to select the card that he is to present as his answer. 

 As to the precise association that an animal comes to establish between 

 a certain sign and a certain action, and the number and complexity of 

 such associations that he can master, there is doubtless some variation 

 among animals, though again hardly as much as amongst men. It is 

 also interesting to determine the nature of the signs, whether noted by 

 the ear or the eye, that a dog or a horse most readily learns; but all 

 these details do not at all modify the general nature of the operation, 

 which mainly needs be considered. The actual indication that ' Jim 

 Key ' follows to reach first the right frame, and then the right row, 

 and then the right letter, seems to be given by different positions of 

 the master's whip. The ability to learn even this simple association 

 is probably very limited, and in this case seems never to exceed ' five.' 

 Upon this slender basis of actual achievement, does ' Jim Key ' attain 

 his reputation as a learned thinker. 



The performances of ' Kluge Hans/ so far as they may be gathered 

 from the printed descriptions, are of no more complex character. The 

 method of response is simpler and consists of nothing more than in 

 pawing continuously one stroke after another, and of stopping when 

 the number of strokes corresponds to the answer of the arithmetical 

 problem that has been set. Alphabets and ' yes ' and ' no ' must also 

 be reduced to numbers before they fall within ' Hans's ' repertory. 

 Here again, as announced, the program is most versatile and startling. 

 There is the same proficiency in multiplying and dividing and adding 

 and spelling ; and by an ingenious variation of the question, ' Hans ' 

 will tell how many of the admiring company are over fifty years of 

 age, or are members of a certain profession, and will paw ' yes ' or 

 ' no ' in answer to any question of which his master knows the answer. 

 The claims put forth on behalf of the Berlin horse — and that on the 

 part of men otherwise versed in scientific matters — is indeed remark- 

 able, positively astounding ; for one of these attributes to ' Hans ' a 

 perfect acquaintance with fractions, the ability of distinguishing colors 

 as well as playing-cards, to tell the coins of the realm, to differentiate 

 geometrical figures, to give the time upon any watch-face, to name 

 musical tones and tell which are discords. The method by which these 

 answers are indicated is never more nor less than that of pawing until 

 the correct number is reached. The more complicated replies are in 

 the form of words : for this purpose the elementary sounds are reduced 

 to 42 — allowing for combinations of vowels and consonants. Accord- 

 ingly, any one of these sounds is indicated by occupying one of seven 

 places on one of six rows ; thus for ' // ' Hans ' stamps first 3 times 

 •and then 4 ; and for ' St/ first 5, then 6. Under this system,- the horse 



