594 KARL T. WAUGH 



be conceived as similar to that in which one finds one's self when 

 learning to operate some little mechanical device: 



I go to my locker after a long absence, having forgotten the 

 combination, and as soon as the muscular sensations come in from 

 handling the lock, I find that I am turning the knob to the partic- 

 ular succession of numbers which will open the lock. I become 

 aware of the succession and by attending to the movements I am 

 making, learn the combination from myself. In this case I have 

 been observing the effects of the operation of a motor circuit. 



Supposing I am not particularly anxious to relearn the com- 

 bination ; my attention is on the paraphernalia within the locker. 

 It is possible that I may open the lock without learning the com- 

 bination from myself and may come to the locker again the next 

 day without an idea of the key. Instead of being wholly interested 

 in what I seek, it is only when I fix my attention on the means of 

 attaining it that I am in a position to learn; but I can accomplish 

 my ends perfectly without paying attention to the means, letting 

 the motor circuits do the work, and this is the way, we conceive, 

 that the mouse does in the majority of cases where it is successful. 



Now suppose that after I have become used to a certain combi- 

 nation and can work it unconsciously, the combination is changed 

 and I am told a new one. I receive the new series of numbers and 

 commit it to memory. The next day I go to the locker and find, 

 after working with the knob for some time, that my fingers have 

 been using the old combination. I may even make this same mis- 

 take for several days. This experience we may compare with that 

 of the mouse when the lights are changed. The creature is guided 

 by the effects of the motor circuits within its bodj r to the right side, 

 because it had become habituated to turning to the right when 

 the food was to be obtained on that side. Now that the food is to 

 be obtained on the left, it still goes to the right, and does so over 

 and over again. Each attempt of this sort is of course recorded as 

 a failure. 



How long the animal will continue to run into the wrong com- 

 partment is a question of how long before it will begin to attend 

 to the means to be employed in obtaining the food, or, it is a ques- 

 tion of how long before the impulse to venture in search of food 



