238 On the Vital Principle^ 



adlion, nor the mufcles on the fide irritated ; 

 but their antagonifts contraft immediately and 

 ftrongly * : if the back of the hand, for inftance, 

 be fuddenly irritated, the extenfors of the hand 

 are not affeded, but the flexors are thrown into 

 inftant and violent adlion, to remove the limb 

 from the offending caufe. Now if the inftanta- 

 neous adlion be, in this cafe, chiefly produced 

 by an eliorc of the mind, the fuppofition of 

 a diflinft vital principle is fuperfluous j if it be 

 faid to be produced by the living power inde- 

 dendent of the mind, thert there muft be a 

 rational power in the body, independent of the 

 mind, which is abfurd. 



1. The ftate of the vital and involuntary mo- 

 tions is confiderably affe6led by the ftate of the 

 mind. Refpiration is, to a certain degree, 

 under the direAion of the will: the action M 

 the heart is very quickly and powerfully varied 

 by the workings of the paffions ; and even the 

 fecretions are frequently changed, in quantity 

 and quality j-, by the fame caufe. But farther, 

 thefe motions are often fufpended by a fudden 

 affedion of the mind, as in the cafe of fainting, 

 which is produced very commonly by an im- 

 preflion made on the mind, without the fufpi- 



m 



* Whytt, Vit. and Inv. Mot. 



f The bite of an enraged man has been known to prove 

 fatal, in confequence of the poifonous quality of the 

 faliva. Hoffman, torn. I. 



cion 



