CH. VI.] OLD AGE AND DEATH. 359 



the brain (124, 130, i), but it is not known, whether there 

 be one point only in the whole brain appropriated to con- 

 sciousness and the conceptive force, and which can be termed 

 the seat of the mind. (Consult Haller's ' Physiology,' § 370, 

 sqq.) The difficulties in the way of a correct theory, render 

 it impossible to give any details as to the modes in which 

 the separation of body and soul may take place. 



720, ii. The separation of the soul and body may occur inde- 

 pendently of entire animal death when the conceptive force ceases 

 to act ; that is to say, when those impressions are absolutely 

 wanting, which the brain can duly receive in virtue of its animal- 

 sentient forces. If the soul be considered as a substance distinct 

 from the body, cases may be imagined, in which it may separate 

 itself from the body, the animal-sentient forces of the brain 

 being altogether unaffected, as is supposed to occur in the trans- 

 migration of souls. But it is fixed by the eternal laws of 

 nature, that no conception can occur without the co-operation 

 of the animal-sentient force, and no material ideas arise in the 

 brain, without the co-operation of the conceptive force. Con- 

 sequently, all possible modes of dissolution in the ordinary 

 acceptation of the word, are comprised in those stated, § 718. 



721 — 726. Dissolution of the connection between body and 

 mind must take place, whenever complete animal death occurs, 

 and will be caused — 



i. By whatever entirely arrests the action of the heart (711), 

 and thereby arrests the functions of the brain and its animal- 

 sentient forces (718). But so long as interruption of the cardiac 

 action fails completely to effect this, the animal is neither 

 absolutely nor mentally dead. ii. By whatever abolishes the 

 primary vital force of the brain, and, consequently, the secre- 

 tion and distribution of the vital spirits, so that the action 

 of the animal-sentient force is quite arrested (712). iii. By 

 whatever abolishes both the primary vital forces at once, or by 

 abolishing one destroys the other, and thus complete animal 

 death takes place (713). iv. By whatever at once renders the 

 whole system of animal machines unfit for its function, and, 

 consequently, for the animal-sentient forces (714). If this 

 occurs gradually, the dissolution of the connection of body 

 and soul, may precede complete animal death. In death 

 by lightning, both take place at the same time. If the 

 animal machines be only rendered partially unfit for their 



