396 ZOOLOGICAL PHILOSOPHY 



thoughts which ought to be produced ; the intellectual faculties are 

 then suspended or in disorder. 



We shall see that lunacy is also due to a very similar cause, which 

 prevents the inner feehng from directing the movements of the nervous 

 fluid into the hypocephalon. 



In fact, when any accidental injury has caused some disturbance in 

 the organ of intellect, or when a powerful emotion of the inner feehng 

 has left upon this organ traces deep enough to produce some degenera- 

 tion in it, the inner feehng no longer controls the movements of the 

 nervous fluid in that organ, and the ideas raised in the individual by 

 the agitations of the fluid present themselves without any order or 

 connection. He gives expression to whatever occurs to him, and his 

 actions are of a corresponding kind. But we see from the acts of this 

 individual that he is always affected by ideas previously acquired 

 and then brought into consciousness. In point of fact memory, 

 dreams, dehrium, acts of lunacy, never bring out any ideas beyond 

 those already possessed by the individual. 



There are some acts of lunacy which follow from a disorder of certain 

 special organs of the hypocephalon, while the others maintain their 

 integrity ; it is then only in these special organs that the inner feehng 

 cannot control or direct the movements of the nervous fluid. People 

 who are affected in this way only perform acts of lunacy with regard to 

 certain subjects that never vary : they appear to be in possession of 

 their reason on all other subjects. 



I should travel beyond my province if I tried to follow all the dis- 

 tinctions observed in the disorder of ideas, and to ascertain their causes. 

 It is enough to have shown that dreams, deUrium, and lunacy in general 

 are only disordered acts of memory which always work upon ideas 

 previously acquired and impressed on the organs, but which are beyond 

 the control of the individual's inner feehng, because the functions of 

 this power are suspended or disturbed, or because the state of the 

 hypocephalon does not permit of their performance. 



Cabanis had no idea of the strength of the inner feehng, nor did he 

 perceive that this feehng constitutes in us a power that can be stirred 

 by any need, or by the smallest desire, or by a thought, and that it is 

 then able to set in motion the free portion of the nervous fluid and to 

 direct its movements either into our organ of intelhgence, or towards 

 muscles which require to be actuated. Yet he was forced to recognise 

 that the nervous system often enters into activity of its own accord, 

 without the stimulus of external impressions, and that it can even 

 disregard these impressions and escape from their influence, since 

 concentrated attention or deep thought suspend the activity of the 

 external organs of feehng. 



