INTRODUCTION. xliii 



" Reason, or intelligence, is the faculty which is concerned in the intentional adap- 

 tation of means to ends. It therefore implies the conscious knowledge of the relation 

 between means employed and ends attained, and may be exercised in adaptation to 

 circumstances novel alike to the experience of the individual and to that of the 

 species." 



It would appear, then, that animals have, in some slight degree, what we call mind, 

 with its threefold divisions of the sensibilities, intellect, and will. When we study animals 

 in a state of domestication, especially the dog or horse, we know that they are capable of 

 some degree of education, and that they transmit the new traits or habits which they 

 have been taught to their offspring ; so that what in the parents were newly acquired 

 habits become in the descendants instinctive acts. We are thus led to suppose that 

 the terse definition of instinct, by Murphy, that it is ' the sum of inherited habits,' is 

 in accordance with observed facts. Indeed, if animals have sufficient intelligence to 

 meet the extraordinary emergencies of their lives, their daily so-called instinctive acts, 

 requiring a minimum expenditure of mental energy, may have originated in previous 

 generations ; and this suggests that the instincts of the present generation may be the 

 sum total of the inherited mental experiences of former generations. 



Descartes believed that animals were automata. Lamarck expressed the opinion 

 that instincts were due to certain inherent inclinations arising from habits impressed 

 upon the organs of the animals concerned in producing them. 



Darwin does not attempt any definition of instinct ; but he suggests that ' several 

 distinct mental actions are commonly embraced by this term,' and adds that ' a little 

 dose, as Pierre Huber expresses it, of judgment or reason often comes into play, even 

 in animals low in the scale of nature.' He indicates the points of resemblance be- 

 tween instincts and habits, shows that habitual action may become inherited, especially 

 in animals under domestication; and since habitual action does sometimes become 

 inherited, he thinks it follows that " the resemblance between what originally was a 

 habit and an instinct becomes so close as not to be distinguished." He concludes 

 that, by natural selection, slight modifications of instinct which are in any way use- 

 ful accumulate, and thus animals have slowly and gradually, " as small consequences 

 of one general law," acquired, through successive generations, their power of 

 acting instinctively, and that they were not suddenly or specially endowed with 

 instincts. 



Rev. J. J. Murphy, in his work entitled Habit and Intelligence, seems to regard 

 instinct as the sum of inherited habits, remarking that " reason differs from instinct 

 only in being conscious. Instinct is unconscious reason, and reason is conscious in- 

 stinct." This seems equivalent to saying that most of the instincts of the present 

 generation of animals are unconscious automatism, but that in the beginning, in the 

 ancestors of the present races, instincts were more plastic than now, such traits as 

 were useful to the organism being preserved and crystallized, as it were, into the 

 instinctive acts of their lives. This does not exclude the idea that animals, while in 

 some respects automata, occasionally perform acts which transcend instinct ; that they 

 are still modified by circumstances, especially those species which in any way come in 

 contact with man ; are still in a degree free agents, and have unconsciously learned, by 

 success or failure, to adapt themselves to new surroundings. This view is strength- 

 ened by the fact that there is a marked degree of individuality among animals. Some 

 individuals of the same species are much more intelligent than others ; they act as 

 leaders in different operations. Among dogs, horses, and other domestic animals, 



