140 Studies in Animal Behavior 



culiar physiological processes supposed to accom- 

 pany the satisfying and annoying experiences of the 

 animal. Thorndike recognizes that while the ten- 

 dency of animals to repeat responses that bring sat- 

 isfaction or pleasure and to discontinue responses 

 that entail pain usually leads to advantageous re- 

 sults, this rule is not without its exceptions. "Many 

 animals are satisfied by deleterious conditions. Ex- 

 citement, overeating, alcoholic intoxication are, for 

 instance, very potent satisfi'ers of man," and condi- 

 tions which are very salutary often fail to produce 

 satisfaction, and may even bring positive displeas- 

 ure. All this is simply a matter of imperfect ad- 

 justment. "Upon examination," says Thorndike, "it 

 appears that the pernicious states which an animal 

 welcomes are not pernicious at the time, to the neu- 

 rones. We learn many bad habits, such as mor- 

 phinism, because there is incomplete adaptation of 

 all the interests of the body-state to the temporary 

 interest of Its ruling class, the neurones. So also 

 the unsatisfying goods are not goods to the neu- 

 rones at the time. We neglect many benefits be- 

 cause the neurones choose their immediate advan- 

 tage. The neurones must be tricked into permitting 

 the animal to take exercise when freezing or qui- 

 nine when in a fever, or to free the stomach from 

 certain poisons. 



"Satisfaction and discomfort, welcoming and 

 avoiding, thus seem to be related to the mainte- 

 nance and hindrance of the life processes of the neu- 



