GKOWTII OF EMOTIONS IN ANIMALS. 303 



ations was brought into activity by this stimulus, becomes 

 nasccntly excited. Even while yet there have been no indi 

 vidual experiences, a vague feeling of pleasure or pain is 

 produced ; constituting what we may call the body of the 

 emotion. And when the experiences of past generations 

 come to be repeated in the individual, the emotion gains 

 both strength and defiuiteness ; and is accompanied by the 

 appropriate specific ideas. 



This view of the matter, which we believe the estab 

 lished truths of Physiology and Psychology unite in indi 

 cating, and which is the view that generalizes the pheno 

 mena of habit, of national characteristics, of civilization in 

 its moral aspects, at the same time that it gives us a con 

 ception of emotion in its origin and iiltimate nature, may 

 be illustrated from the mental modifications undergone by 

 animals. 



It is well-known that on newly-discovered lands not in 

 habited by man, birds are so devoid of fear as to aUow 

 themselves to be knocked over with sticks ; but that in the 

 course of generations, they acquire such a dread of man as 

 to fly on his approach ; and that this dread is manifested by 

 young as well as old. Now unless this change be ascribed 

 to the killing-oif of the least fearful, and the preservation 

 and multiplication of the more fearful, which, considering 

 the comparatively small number killed by man, is an inade 

 quate cause ; it must be ascribed to accumulated expe 

 riences ; and each experience must be held to have a share 

 in producing it. We must conclude that in each bird that 

 escapes with injuries inflicted by man, or is alarmed by the 

 outcries of other members of the flock (gregarious crea 

 tures of any intelligence being necessarily more or less 

 sympathetic), there is established an association of ideas 

 between the human aspect and the pains, direct and indi 

 rect, suffered from human agency. And we must further 

 conclude, that the state of consciousness which impels the 



