Laws and Hypotheses for Behavior 271 



all once, or reached the one that puts an end to the situa- 

 tion. 



The second limitation may be illustrated in the simple 

 hypothetical case of three responses, i, 2 and 3, of which 

 No. 2 is successful. Suppose the animal always to go 

 through his repertory with no repetitions until he reaches 2 

 and so closes the series. 



Only the following can happen : 



I 2 



132 



2 



2 



312 



3 2 



and, in the long run, 2 will happen twice as often as i or 3 

 happens. 



Suppose the animal to repeat each response of his reper- 

 tory six times before changing to another, the remaining 

 conditions being as above. Then only the following can 



happen : - 



i i i i i i 2 



iiii II333333 2 



2 

 2 



333333 1111112 

 3333332, 



and in the long run 2 will happen one third as often as i or 3 



and, though always successful, must, by Smith's theory, 



appear later and later, so that if the animal meets the 



situation often enough, he will eventually fail utterly in it ! 



Animals do, as a matter of fact, commonly repeat responses 



many times before changing them, 1 so that if only the law 



1 Professor Smith's own experiments illustrate this. 



