310 PHILOSOPHY OF ZOOLOGY. 



pressing the wants or the enjoyments of the active powers. 

 In addition to this natural language, man has contrived ar- 

 tificial sounds, and artificial signs, to express all his percep- 

 tions, reflections, and feelings, to others of his race, absent 

 as well as present, attributes which give him a decided 

 superiority over the brutes. It is by means of these, that 

 the improvements or the experience of one generation are 

 transmitted to another ; so that, while the brutes must ac- 

 quire all their knowledge by experience, man derives his 

 most valuable acquisitions from tradition. 



We have likewise seen, that the power of restraining the 

 impulses of the active powers is weak in the lower ani- 

 mals ; but, in man, it is capable of exerting itself in a great- 

 er degree, thus giving him a more complete command over 

 himself, and consequently over the objects around him. 



These various instances of superiority, unfold to us the 

 steps by which man is destined to rise in the scale of civi- 

 lized life, and acquire that dominion over nature which he 

 upholds by his wisdom. Man, therefore, is far exalted 

 above the brutes, by a superior degree of perfection in his 

 intellectual faculties ; by a greater power of restraint over 

 his instincts ; and by readier methods of communicating his 

 ideas and feelings, rather than by a difference in the na- 

 ture of his mental constitution. 



The importance of the nervous system to the existence 

 and wellbeing of animals, naturally excited inquiries con- 

 cerning its structure and modifications in the different 

 races of animals, and led to the adoption of the charac- 

 ters which these furnished in their classification. We have 

 already presented a view of the animal kingdom, at the 

 conclusion of our remarks on the structure of the nervous 

 system, in which the classes are arranged according to dif- 

 ferences in the organization of this system. 



When we consider the difficulty attending the examina- 

 tion of the functions of the nervous system, our ignorance 



