HUNTERIAN ORATION. 7 



nothing but error and pernicious notions. 

 It is a very great but very common mis- 

 employment of our reasoning powers, to 

 draw inferences from facts belonging to dif- 

 ferent subjects, which are incommensurate 

 with one another. Such irrelevant facts 

 have been often designated by the whimsical 

 and contradictory expression of false facts. 

 We are indeed sometimes induced to reason 

 from analogy, but then the similarity of the 

 facts is so precise, as to warrant us in be- 

 lieving that the subjects, concerning which 

 we thus comparatively reason, are essentially 

 alike. 



Now without any knowledge of anatomy, 

 or the animal economy, persons of the me- 

 dical profession, by drawing inferences from 

 mixed facts, might suppose, that a fire was 

 kindled throughout the body to warm and 

 cherish it, which, if in excess, might set our 

 juices into fermentation, and thus produce 

 partial or general disorder j they might 

 suppose, that there were elements in the 

 body, which ought to be combined in defi- 

 nite proportions, and that different diseases 

 might result from the excess or deficiency 



B 4 



