316 ANIMAL NATURE AS A WHOLE. [in. 



i. The nerves receive external impressions in a manner 

 peculiar to themselves ; that is^ according to their peculiar laws, 

 which accord with neither the physical nor mechanical laws of 

 any other bodies, than animal bodies ; these impressions are 

 transmitted along the nerves to the brain, and laterally by means 

 of branches or ganglia to other nerves, and thereby become 

 animal-motor forces of the mechanical machines with which the 

 nerves are incorporated, as well as animal-sentient forces by 

 means of the brain, for the development of external sensations 

 and sensational conceptions, desires, aversions, instincts, &c., 

 which are developed and connected with each other in the mind, 

 according to the animal laws of the vis nervosa of the external 

 impressions. 



ii. The conceptions of the mind communicate internal im- 

 pressions to the brain, which it receives in a peculiar manner, 

 according to the laws of its own peculiar animal-sentient forces, 

 and transmits along the nerves, whose cerebral origins these con- 

 ceptions excite, to the mechanical machines in which the nerves 

 are distributed, or along their branches, or by means of their 

 ganglia along other nerves going to mechanical machines, and 

 thereby the impressions become motor animal-sentient forces of 

 these machines, and are developed and connected with each 

 other in them, according to the psychological laws of the con- 

 ceptive force ; but which are themselves nevertheless necessarily 

 regulated in the sensational conceptions, by the animal laws of 

 the vis nervosa of external impressions. 



iii. The vis nervosa of external impressions can produce all 

 the sentient actions which sensational conceptions excite, even 

 if the conceptions themselves do not ensue. 



iv. The animal-sentient forces can reproduce the nerve- 

 actions of impressions, when the impressions themselves do not 

 actually take place. 



V. Lastly, the movements excited by unfelt external im- 

 pressions are purely nerve-actions : those excited by the higher 

 passions, intellectual conceptions, desires, aversions, and satis- 

 fyings of the will, are purely sentient actions, and all others are 

 excited by the combined operation of the animal-sentient forces 

 and the vis nervosa. 



