98 The Dancing Mouse 



the entrances between which it is required to discriminate. 

 It is evident that the animal is uncomfortable in a space 

 which is too narrow for it to whirl in freely. It must have 

 room to dance. This furnished a sufficiently strong motive 

 for the entering of the electric-boxes. It must avoid dis- 

 agreeable and unfavorable stimuli. This is a basis for 

 attempts to choose, by visual discrimination, the electric-box 

 in which the shock is not given. It may safely be said that 

 the success of the majority of the experiments of this book 

 depended upon three facts: (i) the dancer's tendency to 

 avoid disagreeable external conditions, (2) its escape-from- 

 confinement-impelling need of space in which to dance freely, 

 and (3) its abundant and incessant activity. 



Of these three conditions of success in the experiments, 

 the second and third made possible the advantageous use of 

 the first. For the avoidance of a disagreeable stimulus could 

 be made use of effectively in the tests just because the mice 

 are so restless and so active. In fact their eagerness to do 

 things is so great that the experimenter, instead of having 

 to wait for them to perform the desired act, often is forced 

 to make them wait while he completes his observation and 

 record. In this respect they are unlike most other animals. 



My experiments with the dancer differ from those which 

 have been made by most students of mammalian behavior 

 in one important respect. I have used punishment instead 

 of reward as the chief motive for the proper performance of 

 the required act. Usually in experiments with mammals 

 hunger has been the motive depended upon. The animals 

 have been required to follow a certain devious path, to 

 escape from a box by working a button, a bolt, a lever, or 

 to gain entrance to a box by the use of teeth, claws, hands, 

 or body weight and thus obtain food as a reward. There are 

 two very serious objections to the use of the desire for food 



