CHAPTER IX 



Ideational Behavior 



The question whether the chick can react on the general 

 basis of triangularity-circularity, largeness-smallness, or rapidity- 

 slowness was suggested primarily by the different positions 

 regarding ideation taken by Thorndike and Cole. Their 

 divergent conclusions concerning the evidence of ideas furnished 

 by infra-human behavior have stimulated considerable subse- 

 quent work. The possibility of my study furnishing data for 

 this problem is suggested in the question : does the chick discrim- 

 inate on the basis of specific stimuli, or on the basis of relative 

 stimulus difference? 



Aside from its ideational bearing, this question has consid- 

 erable significance also for infra-human threshold experimen- 

 tation. If it be found possible to train an animal consistently 

 to choose on the basis of relative stimulus difference, it would 

 seem desirable to present, interspersed with the training stim- 

 ulus setting, other pairs of stimuli differing proportionately 

 by greater and less amounts both above and below the training 

 pair. Such a procedure would tend to distribute the effect 

 of training more evenly through a sequence of daily series. 

 In threshold studies it would make possible a more constant 

 vividness, in the awareness of the subject, of the problem 

 which is presented. In the end, the experimenter could be 

 more certain that the failure of his subject to respond appro- 

 priately was due to the threshold limit and not to indifference 

 to the demands of the problem. 



Because the material that has been gathered on this question 

 of relativity or specificity of chick reactions is wholly incidental 

 to the primary tasks that have been discussed in the preceding 

 chapters, no attempt will be made to present it in detail. The 

 result of these incidental tests with forms has been presented 

 in Chapter VI. The failure of the chick to respond correctly 

 when the triangle was inverted suggests a negative answer 

 to this question of relative form difference. Negative results 

 are also in evidence when the size of the triangle was changed. 



