RESPONSIVE LIFE OF ORGANISMS 



483 



without any misdirected efforts.* When learned thor- 

 oughly, make a tabular record of the time and efforts 

 expended in the process, by successive trials, as follows : 



If any considerable part of the laboratory period remains 

 after one chicken is educated to the act, another may be 

 tried; or the labyrinth may be altered or complicated and 

 the same one re- tried. 



The record of this study will consist of a diagram of the 

 experiment, together with a summary of the results appear- 

 ing in the table. 



Further progress. As the chick has mastered one per- 

 formance so it may master another. With repetition the 

 signs of effort disappear and those of habit take their place. 



It is a long step forward toward intelligence when brain 

 circuits are able to retain impressions arising from one 

 stimulus long enough to influence the action that shall result 

 from the next stimulus of the same kind; for then the 

 responses may begin to take on individual variations. It is 

 a still longer step when the central circuits through previous 

 stimulation and mutual interaction become able to originate 

 like acts in absence of the original stimuli ; for here initiative 

 comes in. Then, the trial of a performance need not wait 



*It is best that the chicken should be quite unmolested by the 

 observers during the experiment, but if unfortunate conditions 

 should have made it sluggish in action (so that it inclines to squat 

 and do nothing), results may still be had by applying any sort 

 of gentle stimulus that does not tend to urge it in any particular 

 direction, such as dropping the end of a cane against the bottom 

 of the box. 



