242 



F. M. GREGG AND C. A. McPHEETERS 



card was exhibited three times in succession ; the animal was 

 taught to respond during the third presentation, and the re- 

 sponse consisted of an inhibition, i.e., the animal must remain 

 off the steps. This inhibitory response was inculcated without 

 a food reward. 



Three animals learned the discrimination, and Cole makes 

 three questionable assumptions as to facts: — (i), The t discrimi- 

 nation was mediated through vision; (2), it was based upon 

 card distinctions (presumably differences in color and bright- 

 ness), and (3), all three presentations of each series were effec- 



rs=^ 



Figure 1. Dr. Cole's color-displaying device and feeding block 



tive components of the stimulus. His evidence upon this latter 

 point consists of the fact that the response generally occurred 

 during the presentation of the third card. Since this third 

 member was identical for the two series, it, in and of itself, 

 could furnish no' basis for the two differential responses. In 

 case of premature responses, i.e., attempts to mount the steps 

 before the third card was presented, Cole observed that the 

 animal frequently stopped and looked around when this final 

 card was presented. This behavior indicates that the final 

 red card "was not a neglected element of the situation." 



The argument in favor of the existence of images takes two 

 forms and each involves a questionable assumption of theory: — 



2 Op. cit., p. 258. 



