CHAPTER XV. 



INSTINCT AND EEASON IN ANIMALS. 



WE have seen that animals have organs of sense, of per- 

 ception, in many cases nearly as highly developed as in man, 

 and that in the mammalia the eyes, ears, organs of smell 

 and touch differ but slightly from those of our own species ; 

 also that the brain and nervous system of the higher mam- 

 mals closely approximate to those of man. We know that 

 all animals are endowed with sufficient intelligence to meet 

 the ordinary exigencies of life, and that some insects, birds, 

 and mammals are able, on occasion, to meet extraordinary 

 emergencies in other words, to rise with the occasion. 

 These occurrences indicate that what usually goes by the 

 name of " instinct ' : is more or less pliable, unstable; 

 that animals are in a limited degree free agents, with powers 

 of choice. Moreover, those naturalists who observe most 

 closely and patiently the habits of animals do not hesitate 

 to state their belief that animals, and some more than 

 others, possess reasoning powers which differ in degree 

 rather than in kind from the purely intellectual acts of 

 man. 



As a matter of not infrequent observation, animals exer- 

 cise the power of choice, they select this or that kind of 

 food, prefer this or that kind of odor, and have their likes 

 and dislikes to certain persons, and all this aside from mere 

 physical stimulation of the senses. Moreover, animals are 

 subject to the passions, they show anger, even when not 

 hungry or under the domination of the reproductive in- 

 stincts ; their sounds express dissatisfaction or contentment. 

 Indeed, many facts could be stated showing that animals 



