822 



SCIENCE. 



[N. S. Vol. VII. No. 181. 



tion in the mental process involved when a 

 man learns to play tennis or billiards or to 

 swim. Both contain sense-impressions, im- 

 pulses, acts, and possibly representations. 

 Both are learned gradually. Such human 

 associations cannot be formed by imitation 

 or by being put through the movement. 

 ISTor do its elements have any independent 

 existence in a life of free ideas apart 

 from their place in the associations. No 

 tennis player's stream of thought is filled 

 with representations of the tens of thous- 

 ands of sights he has seen or movements 

 he has made on the tennis-court, though 

 his whole attention was on them at the 

 time. 



The great step in the evolution of human 

 intellection is then not a jump to reason 

 through language, but a change from a 

 consciousness which equals a lot of specific 

 connections to a consciousness which in- 

 cludes a multitude of free ideas. This is 

 the prerequisite of all the human advance. 

 Once get free ideas in abundance, and com- 

 parison, feelings of transition or relation, 

 abstractions and ' meanings ' of all sorts 

 may emerge. In this respect, as in imita- 

 tion, the monkeys bear the marks of their 

 relationship. 



Besides the experiments resulting in this 

 new analysis of the mental processes of 

 animals, others were made to discover the 

 delicacy, complexity, number and perma- 

 nence of their associations. It was found 

 that naturally they discriminate very little, 

 that what they react to is a vague, unana- 

 lyzed total situation. Thus, cats that had 

 learned to climb up the front of a cage on 

 hearing the words, ' I must feed those 

 cats,' would climb up just as readily if you 

 said, ' What time is it ? ' or any short sen- 

 tence. By associating only the right re- 

 action with pleasure, however, you can 

 render the association delicate to any de- 

 gree consistent with their sense powers. 

 For instance, a cat was taken that was just 



beginning to form the association between 

 the words, ' I must feed those cats,' and 

 the act of climbing up the front of the cage 

 (after she climbed up she was given a bit 

 of fish). She was now given a lot of trials, 

 some as just described, some with the sig- 

 nal changed to, ' I will not feed them.' At 

 these trials she got no fish. The purpose 

 was to see how many trials would be re- 

 quired before she would learn always to 

 climb up at the " I must feed " and always 

 stay down at the " I will not." The two 

 sorts of trials were mixed indiscriminately. 

 60 of the "I must feed"'s were, in addi- 

 tion to its previous training, enough to 

 make the proper reaction to it inevitable. 

 380 of the ' I will not ' 's were required 

 before perfect discrimination between it and 

 the former signal was attained. 



It was found that complex associations 

 (such, e.g., as the way to escape from a box 

 where the door fell open only after a plat- 

 form had been pushed down, a string clawed 

 and a bar turned around) were very slowly 

 formed and never really formed at all. 

 That is, the animals did not get so that they 

 went through the several acts in a regular 

 order and without repeating uselessly one 

 element. In respect to delicacy and com- 

 plexity, then, we see a tremendous differ- 

 ence between association in animals and as- 

 sociation in man. 



Equally great is the difference in num- 

 ber. A practised billiard player has more 

 associations due to just this one pastime 

 than a dog has for his whole life's activity. 

 The increase in the number of associations 

 is a sign, and very likely a cause, of the ad- 

 vance to a life of free ideas. Yet, small as 

 it is, in comparison with our own, the num- 

 ber of associations which an animal may 

 acquire is probably much larger than pre- 

 vious writers have fancied. 



A great many experiments were made on 

 the permanence of associations after from 

 10 to 70 days. Samples of the results will 



