On the Vital Principle. a 17 



on medical theories at prefent, but the opinion 

 of a vital principle is chiefly direfled, to explain 

 thofe aflions of the living body, both in health 

 and difeafe, which become the moft important 

 obje6ls of a phyfician's attention j and as it feems 

 calculated to refliore the theory of occult quali- 

 ties, under the fpecious title of principles, fhould 

 it extend itfelf among perfons lefs enlightened 

 than its prefent defenders, a view of its founda- 

 tion, and its connexion with fafts, becomes 

 defirable. 



The immateriality of the foul was admitted 

 by moft of the ancient philofophers*, but the 

 reciprocal a6tion of the foul and body on each 

 other, in the phsenomena of fenfation and volun- 

 tary motion, were not eafily explained on that 

 fuppofition. To get rid of this difficulty, 

 Plato, improving perhaps on the opinion attri- 

 buted to Pythagorasf, propofed that of a plaftic 

 nature, incorporeal indeed, but without con- 

 fcioufnefs:{:, and forming the medium between 

 the foul and body. This doftrine appears to 

 have been varioufly modified by different feds, 

 but believed, to a certain extent, by all till the 

 time of Ariftotle. Mr. Barthez, in his learned 



• That is its diftinftion from matter, though not in the 

 fenfe of the modern immaterialifts. 



f Of an Anjma Mundi, from which the fouls of men 

 were emanations. Veil, in Cic. de Nat. Deor. 



; Cudworth's Intelleft. Syft. p. 158, 165, 166. 



treat ile 



