Modification by Experience 



235 



less than in a labyrinth, the adult rats solved the problems 

 in less time than that occupied by the young ones (430). 



In Thorndike's work on cats and dogs, the investigator 

 placed the animals themselves in the boxes, and food on the 

 outside, so that the problem was not how to get in but how 

 to get out. The getting out could be accomplished in various 



FIG. 17. Puzzle box used in Thorndike's experiments on cats. 



ways, such as pulling a wire loop, clawing a button around, 

 pulling a string at the top of the box, poking a paw out and 

 clawing a string outside, raising a thumb latch and pushing 

 against the door, and so on (Fig. 17). The animals, on 

 being first put into the box, made all sorts of movements 

 in their struggles to get out; the right movement was hit 

 upon by accident. Only very gradually, as the experiment 

 was repeated again and again, were the useless movements 

 omitted, until finally the right one was performed at once 

 (393)- Wesley Mills has criticised these pioneer experi- 

 ments of Thorndike's on the ground that the animals were 

 under such unnatural conditions and in such an extreme 

 state of hunger that they profited by experience more slowly 



