JOHN HUNTER. 497 



the same tissue, it is presumptive proof that 

 nothing material is conveyed from one to the 

 other ; but that sensations and volitions are only 

 a species of nervous action. So contradictory 

 and unsettled were all his notions on this im- 

 portant subject, that he again represents " the 

 stomach as the seat of the materia vita, and 

 thereby the organ of universal sympathy ;" to 

 which he referred " the sensations of heat and 

 cold that attend many diseases." In another 

 place he confounds the organizing principle with 

 " a certain species of motion," in the same way 

 that Bacon, Rumford, and others, confounded 

 heat with motion ; or as the disciples of Sir Isaac 

 Newton have confounded the cause of attraction 

 and repulsion with mechanical force. To complete 

 the problem of contradictions, Hunter finally 

 observes, that " life is a property we do not un- 

 derstand." 



In accordance with the doctrine of Cullen, 

 who rejected Dr. Black's theory of respiration as 

 the exclusive source of animal temperature, 

 Hunter maintained that " the degree of heat in 

 animals is in proportion to the quantity of their 

 life:' (Phil. Trans, vol. 66.) But it might as 

 well be said that the degrees of heat through- 

 out the earth, from the equator to the poles, are in 

 proportion to the quantity of animal and vege- 

 table life. Had this great anatomist known that 

 all the physico-chemical and vital operations that 



