CH. I.] ANIMAL NATURE IN GENERAL. 313 



ments which either cannot be caused by external stimuli, or 

 else require the co-operation of others that they may go on 

 uninterruptedly; their continuance being necessary to the main- 

 tenance of life in the animal. Consequently, they are to be 

 particularly observed in the vital movements and in the viscera, 

 the functions of which are the most necessary to the preserva- 

 tion of the animal (515, 525, 532). The stimuli to the move- 

 ments thus induced, being deeply hid in the interior of the 

 medulla of the nerves, and traceable to no external cause, we 

 infer erroneously that the movements themselves are the re- 

 sult, either of obscure sensations, or of other and volitional 

 conceptions. 



610. The movements necessary to existence, preservation, 

 and other objects of nature, in insentient animals, are effected 

 wholly in them by means of the vis nervosa, and in some degree 

 in the same way as in sentient animals; so that they are capable 

 of movements, which experience and observation prove may be 

 effected without the co-operation of the cerebral forces ; that is 

 to say, they are capable of muscular action, and the appa- 

 rently voluntary movements, the movements of the heart, and 

 the circulation of the fluids ; the arterial pulse ; the flow of 

 humors to an irritated part ; the movements of the diaphragm ; 

 the animal mechanism of respiration ; digestion and peristaltic 

 action ; glandular secretion and excretion ; and the animal 

 functions of the lungs, — of the liver in the secretion and excre- 

 tion of the bile, — of the kidneys and urinary bladder in the 

 secretion and excretion of urine, — and of the sexual organs in 

 the propagation of the species (445 — 481, 507 — 540) . 



611. Insentient animals can also excite, by the vis nervosa 

 alone, according to its animal laws, all those animal movements 

 which are excited in sentient animals by means of the animal- 

 sentient forces of the sensational faculty [Sinnlichkeit] ; de- 

 veloping them in the same order, connecting them with each 

 other in the same way, and just as consecutively as when the 

 movements constitute sentient actions of sensational concep- 

 tions; that is to say, the vis nervosa excites the same move- 

 ments in insentient animals, as constitute the sentient actions 

 of external sensations (433, 439) ; of imaginations and of fore- 

 seeings; of sensational desires, aversions, and instincts; namely, 

 of the alimentative instinct, of the instincts for volitional move- 



