246 NOTES ON THE NATURE OF INSANITY. 



to contend that insanity is not a disease of the brain, because dis- 

 eased brain does not always produce diseased manifestations of the 

 mind. The fact, however, affords a conclusive reason for affirming, 

 that different parts of the brain execute different and peculiar func- 

 tions. 



Having thus seen, that there is always some debasing alteration 

 in the mental manifestations, during insanity ; and that such alter- 

 ation is accompanied with diseased action or with disorganization of 

 the brain, in cases of insanity ; we arrive at the conclusion, that 

 Insanity is a disease of the Brain, causing an alteration in the 

 mental manifestations. Let us next endeavour to determine the 

 extent in which this alteration must exist before we can pronounce 

 an individual to be insane. According to the general opinion, every 

 insane person is totally unfit to manage his affairs, and is dangerous 

 to society : but it can be shown, that there are as many degrees of 

 insanity as there are of other diseases ; and that, in the same way 

 as some bodily diseases are too trifling to interrupt the ordinary 

 course of a man's pursuits, so there are states of insanity which 

 neither require restraint nor incapacitate a person for the various 

 duties of life. Before it becomes necessary to treat an individual 

 as insane by interfering with his natural liberty, we must be able 

 to distinguish some alteration in the manifestations of his mind. Now 

 this alteration may exhibit itself in various modes, as regards the ani- 

 mal propensities, the moral sentiments, or the intellectual powers ; 

 but however extraordinary it may become both in mode and degree, 

 as long as a man's conduct, in words or actions, displays no tendency 

 to injure himself or others, so long he possesses a right to be regard- 

 ed as a free and responsible agent. His insanity can only be deter- 

 mined with the two-fold test — alteration in his mental manifesta- 

 tions, and persistence in conduct adapted to injure his own interests 

 or those of others. 



