MENTAL FACULTIES. 301 



the nerves. It is the latter only or physical pain that concerns us 

 at present. Like every other sensation, although it may be referred 

 exclusively to the part impressed, pain requires the intervention of the 

 encephalon ; for if the nerves, proceeding from a part to that organ, 

 be cut, tied, compressed, or stupefied by narcotics ; or if the action of 

 the brain itself be blunted from any cause, as by the use of opium, 

 ether, or chloroform, or by any compression, accidental or other, the 

 sensation is no longer experienced. We can thus understand why pain 

 is felt less during sleep; and the astonishing cases of resistance to pain, 

 witnessed in the lunatic, and in religious or other enthusiasts who have 

 been subjected to bodily torture. An opposite condition of the nerv- 

 ous system is the cause of the great sensibility to impressions in the 

 nervous and hysterical. 



It is obvious, that pain may be either an external or internal sensa- 

 tion, according as the cause of irritation is extraneous, or seated in 

 the tissue of organs ; and that it must vary considerably, both as re- 

 gards the precise irritant, and the part affected ; hence the difference 

 between the pain caused by a burn, and that by a cutting instrument; 

 and the immense variety of pains to which the human frame is sub- 

 ject, and the attentive study of which is so indispensable to the patho- 

 logist. 



So much for the sensations. These, we have seen, are innumerable, 

 for each sense is capable of myriads of different impressions. We now 

 pass to the consideration of those functions that enable man although 

 worse provided with means of defence and offence than the beasts sur- 

 rounding him, and possessing no covering to protect him from the sum- 

 mer's heat or the winter's cold to provide himself means of defence ; 

 to render the animals around him subservient to his use ; to cover his 

 nakedness, and protect himself against atmospheric changes ; to devise 

 mechanical arts ; to fathom the laws, that govern the bodies by which 

 he is surrounded, and to establish himself undisputed master of the 

 earth. 



MENTAL FACULTIES. 



The external senses convey to the brain the different impressions 

 made upon them by surrounding bodies ; but, of themselves, they 

 would be unable to instruct the mind regarding the universe. It is 

 necessary, that the brain should act before any perception of them can 

 exist. The mental faculties, in other words, convert the impressions 

 into ideas. The internal sensations, on the other hand, consist, as we 

 have seen, of the numerous wants and appetites necessary for the pre- 

 servation of the individual, and the species. In addition to these, man 

 possesses another series of faculties, which influence his character and 

 disposition, and direct his social existence : these are the affective or 

 emotive faculties or faculties of the heart. The study of these different 

 mental and moral phenomena constitutes what has been called psycho- 

 logy, so termed from an idea, that they are exclusively dependent 

 upon the mind. The notion was, at one time, universal, and hence the 

 appellation metaphysician, applied to such as were considered to pro- 

 ceed in their investigations beyond what was physical, material, or cor- 

 poreal. 



