228 The Dancing Mouse 



the modifiability of behavior in the dancer with great accuracy, 

 but, as will now be made apparent, the discrimination method 

 proved to be a far more accurate method for this purpose. 



Once more I should emphasize the fact that my statements 

 concerning the value of methods apply especially to the 

 dancing mouse. Certain of the tests which have proved to 

 be almost ideal in my study of this peculiar little rodent would 

 be useless in the study of many other mammals. An ex- 

 perimenter must work out his methods step by step in the 

 light of the daily results of patient and intelligent observa- 

 tion of the motor capacity, habits, instincts, temperament, 

 imitative tendency, intelligence, hardihood, and life-span of 

 the animal which he is studying. The fact that punishment 

 has proved to be more satisfactory than reward in experiments 

 with the dancer does not justify the inference that it is more 

 satisfactory in the case of the rat, cat, dog, or monkey. Meth- 

 ods which yielded me only qualitative results, if applied to 

 other mammals might give accurate quantitative results; 

 and, on the other hand, the discrimination method, which has 

 proved invaluable for my quantitative work, might yield only 

 qualitative results when applied to another kind of animal. 



The form of the discrimination method whose results are 

 to be presented in this chapter has already been described 

 as white-black discrimination. In the discrimination box 

 (Figures 14 and 15, p. 92) the two electric-boxes which were 

 otherwise exactly alike in appearance were rendered dis- 

 criminable for the mouse by the presence of white cardboards 

 in one and black cardboards in the other. In order to escape 

 from the narrow space before the entrances to the two elec- 

 tric-boxes, the dancer was required to enter the white box. 

 If it entered the black box a weak electric shock was experi- 

 enced. After two series of ten tests each, during which the 

 animal was permitted to choose either the white or the black 



