-.Q E. L. TIIORNDIKE. 



value to these results which was especially aimed at by the 

 investigator from the start. They furnish a quantitative esti- 

 mate of what the average cat can do, so that if any one has an 

 animal which he thinks has shown superior intelligence or per- 

 haps reasoning power, he may test his observations and opinion 

 by taking the time-curves of the animal in such boxes as I 

 have described.^ 



If his animal in a number of cases forms the associations 

 very much more quickly, or deals with the situation in a more 

 intelligent fashion than my cats did, then he may have ground 

 for claiming in his individual a variation toward greater intelli- 

 gence and possibly intelligence of a different order. On the 

 other hand, if the animal fails to rise above the type in his deal- 

 incTs with the boxes, the observer should confess that his opinion 

 of the animal's intelligence may have been at fault and should 

 look for a correction of it. 



We have in these time-curves a fairly adequate measure of 

 what the ordinary cat can do, and how it does it, and in similar 

 curves soon to be presented a less adequate measure of what a 

 dog may do. If other investigators, if especially all amateurs 

 who are interested in animal intelligence, will take other cats 

 and dogs, especially those supposed by owners to be extraordi- 

 narily intelligent, and experiment with them in this way, we 

 shall soon get a notion of how much variation there is among 

 animals in the direction of more or superior intelligence. The 

 beginning here made is meager but solid. The knowledge it 

 gives needs to be much extended. The variations found in in- 

 dividuals should be correlated not merely with supposed superi- 

 ority in intelligence, a factor too vague to be very serviceable, 

 but with observed differences in vigor, attention, memory and 

 muscular skill. No phenomena are more capable of exact and 

 thorough investigation by experiment than the associations of 

 animal consciousness. Never will you get a better psycholog- 

 ical subject than a hungry cat. When the crude beginnings of 

 this research have been improved and replaced by more ingen- 



1 To any such person who may chance to read this monograph I may say 

 that I will gladly furnish him photographs of the boxes, so that he may work 

 with exact duplicates of them. 



