220 ANIMAL FORCES. [ii. 



animal-sentient force. But if an irritation of the medulla of 

 the nerve constituted the internal impression, and if it did not 

 depart from the point of consciousness, that is to say, from the 

 locality of the material idea of a conception, then it is not an 

 animal-sentient force, and the resulting movements, although 

 similar to sentient actions, are not such, but nerve-actions of a 

 vis nervosa. This may be termed the internal feeling of the 

 nerves, to distinguish it from internal sensations (80, 121). 



406. This internal feeling of the nerves, or what is identical 

 therewith, the internal impression not produced by concep- 

 tions, is that animal force of the nerves, in virtue of which 

 they receive in their medulla a certain impression, not mental 

 in its origin, and communicated to them in the direction 

 from above downwards ; transmit the impression thus received 

 in the same direction to their minutest fibrils ; and excite in 

 the mechanical machines with which their fibrils are incor- 

 porated, the same movements as would have occurred if the 

 impression had originated from conceptions. It is a property 

 peculiar to and innate in the nerves, in virtue of which a 

 stimulus applied to their medulla in the direction from above 

 downwards excites hidden movements in them, which no other 

 bodies and no purely mechanical machines could acquire from 

 such a stimulus, and which are not subject to the physical 

 and mechanical laws of motion. These hidden movements 

 are propagated by the nerves to the mechanical machines to 

 which they are distributed, if no hindrance arise, and move 

 them in the same way as they are usually moved by con- 

 ceptions. 



407. According to these views as to the distinction between 

 the cerebral force and the internal feeling of the nerves, it 

 follows, that it is manifestly erroneous to say (as is said in our 

 elementary works), that the animal movements excited by the 

 internal impression are mental, or at least, cerebral. Hence 

 have arisen the erroneous views, which have had so injurious 

 an influence on pathology and therapeutics ; to the effect that 

 the phenomena of fevers, spasmodic diseases, epilepsy, paralysis, 

 and all nervous diseases in general, depend upon some aff^ection 

 of the brain, and that they must be cured by remedies which 

 act upon that viscus. On the contrary, an internal impression 

 excited in nerves far distant from the brain by various irritating 



