Modification by Experience 309 



other animals (it will be recalled that the horse was the 

 stupidest of all Hamilton's subjects), certain indications 

 point clearly away from the possibiHty that the horses 

 are really mathematical geniuses, (i) They learn too 

 quickly to aUow of their understanding. A gifted human 

 being could not acquire so fast a real apprehension of 

 mathematical relationships. (2) They take no longer for 

 hard problems than for easy ones. (3) They begin tapping 

 without even glancing at the problem written on the 

 board. (4) The character of the mistakes they make is 

 not that of the mistakes of a real calculator : very common 

 errors are reversals of the figures, thus 27 for 72, or errors 

 of one unit, as 21 instead of 22. These are errors which 

 might easily be made if the two forefeet were confused in 

 the tapping, or if the tapping stopped a Httle too soon or 

 not quite soon enough. They are not real arithmetical 

 errors, such as forgetting to carry a figure over from one 

 column to another, for instance. P^ No really satisfactory 

 results have been reported when no one present knew the 

 correct answer. On the whole, the phenomena do not 

 present themselves with such authority as to compel a 

 revision of our whole conception of the animal mind (125, 

 126, 2oo,.278, 383, 459, 460, 489, 511, 577 a, 653). 



§ 80. Certain Influences Affecting Learning 



We may conclude our study of the modification of con- 

 scious processes by individual experience with a brief sum- 

 mary of some incidental factors which affect the learning 

 process, (i) The age of the animal has an influence upon 

 its ability to learn. Watson (766) compared the ability 

 of young white rats with that of mature animals in the 

 learning of puzzle-box and maze habits. He was espe- 



