LECTURE I. 43 



to realize the speculations of philosophers, 

 and to verify the deductions of reason, by 

 demonstrating the existence of a subtile, 

 active, vital principle, pervading all nature 

 as has heretofore been surmised, and deno- 

 minated the Anima Mundi. The opinions 

 which in former times were a justifiable 

 hypothesis, seem to me now to be converted 

 into a rational theory. 



Tt is then, I think, manifest, that Mr. 

 Hunter's Theory of Life, presents us with 

 the most probable solution of the phaeno- 

 mena of irritability, of any that has hitherto 

 been proposed. 



The human mind has been the same at all 

 periods of the world ; in all ages there have 

 been men of a sceptical disposition, disin- 

 clined to believe any thing that was not 

 directly an object of their senses. At all 

 periods there have been other men of a^con- 

 templative, and perhaps more credulous 

 character, who have been disposed to believe 

 that there were invisible causes, operating 

 to produce the alterations which are visible. 



