226 The Animal Mind 



difficult to remember, in the image- forming sense, the later 

 turns, but surely "turn to the right" or "turn to the left" 

 would present itself in some sort of terms at the entrance, if 

 the animal could have memory ideas at all. Furthermore, it 

 is very difficult to interpret the learning process here as a case 

 of association of ideas. In Small's labyrinth, two kinds of 

 errors could be made: the one would land the animal in a 

 cul-de-sac, the other simply meant taking a longer passage 

 when a shorter one would suffice. If the former came to be 

 avoided as the result of the calling up of a memory idea, this 

 idea might be that of being brought up short and compelled 

 to retrace one's steps, but how are we to imagine the idea 

 of a shorter path as balanced against that of a longer path ? 

 Small says they must be "distance or temporal ideas in tactual- 

 motor terms," and urges that our own lack of experience of 

 such ideas should not make us doubt their existence in the 

 rat mind; but Thorndike's position, that no ideas are in- 

 volved at all, that the rat merely comes gradually to "feel 

 like" taking one turn rather than the other, seems more 

 probable. 1 In other words, we have the formation of a habit 

 of movement rather than an association of ideas. 



But though ideas may not be involved, the further question 

 remains as to what kind of peripherally excited sensations are 

 influential in the learning process. This question really 

 resolves itself into two. First, by what "clews" does the 

 animal guide itself in learning the labyrinth path? Second, 

 do these clews continue necessary to its guidance when the 

 habit is formed? The two parts of the problem have not 

 always been kept distinct by those who have used the method. 



As regards the first part, Small obtained evidence that his 

 white rats were not guided merely by the smell of their own 

 tracks in finding their way to the centre of the maze, from 



1 See his review of Small's work, Psych. Rev., vol. 8, p. 643. 



