Intelligence and the Acquisition of Habits. 149 



taste, so that on a subsequent occasion its peculiar 

 appearance suggests its peculiar nastiness. What is the 

 connection between the nastiness of a cinnabar caterpillar 

 and the checking of the tendency to eat it, or between the 

 niceness of the caterpillar of the small white butterfly, and 

 the added energy with which it is seized ? Why do taste- 

 stimuli of one kind have the one effect, and taste-stimuli 

 of a different kind have just the opposite effect? What 

 are the physiological concomitants of the augmentation of 

 response in the one case, and of the inhibition of response 

 in the other case ? I conceive that there is but one honest 

 answer to these questions. We do not know. This and 

 much beside must be left for the science of the future to 

 explain. This much may, however, be said. Certain 

 stimuli call forth disturbances, probably in the cortex of 

 the brain, the result of which is the inhibition of activities 

 leading to the repetition of these stimuli ; certain others 

 call forth cortical disturbances, the result of which is the 

 augmentation of the activities which lead to their repetition. 

 The accompaniments in consciousness of the former we call 

 unpleasant or painful ; the accompaniments in con- 

 sciousness of the latter we call pleasurable. This appears 

 to be a plain statement of the facts as we at present 

 understand them.* 



Now, there can be no question as to the strongly-marked 

 hereditary element in such augmentation of response when 

 the cortical disturbances have pleasurable concomitants 

 and the inhibition of response when the cortical disturb- 

 ances have unpleasant concomitants. This is, in fact, 

 founded on the innate powers or faculties which the 

 organism derives from its parents and more distant 



* Compare Prof. J. Mark Baldwin's statementa in his " Mental Develop- 

 ment of the Child and the Eaoe" (1895), p. 278 and elsewhere, concerning 

 what he terms "biological or organic imitation." 



