144 



Animal Intelligence 



C 



FIG. 23. 



it jumped to B and, after a similar process, to C. After 

 enough trials it forms the habit and when put on A goes 



immediately to B, then 

 to C and down. Now 

 if, after 75 or 80 trials, 

 you take away the 

 screens, giving the chick 

 a free chance to go to D 

 from either A or B, and 

 then put it on A, the 

 following phenomenon 

 appears. The chick goes 

 up to the edge, looks over, walks up and down it for a while, 

 still looking down at the chicks below, and then goes and 

 jumps to B as habit has taught it to do. The same actions 

 take place on B. No matter how clearly the chick sees 

 the chance to jump to D, it does not do so. The impulse has 

 been truly inhibited. It is not the mere habit of going the 

 other way, but the impossibility of going that way. In one 

 case I observed a chick in whom the instinct was all but, yet 

 not quite, inhibited. When tried without the screen, it went 

 up to the edge to look over nine times, and at last, after 

 seven minutes, did jump straight down. 



ATTENTION 



I have presupposed throughout one function which it 

 will be well to now recognize explicitly, attention. As 

 usual, attention emphasizes and facilitates the process 

 which it accompanies. Unless the sense-impression is 

 focussed by attention, it will not be associated with the 

 act which comes later. Unless two differing boxes are at- 

 tended to, there will be no difference in the reactions to 



