62 HUME I 



of philosophy is denied, on the one hand, by the 

 " pure metaphysicians," who attempt to base the 

 theory of knowing upon supposed necessary and 

 universal truths, and assert that scientific observa- 

 tion is impossible unless such truths are already 

 known or implied: which, to those who are not 

 " pure metaphysicians," seems very much as if one 

 should say that the fall of a stone cannot be 

 observed, unless the law of gravitation is already 

 in the mind of the observer. 



On the other hand, the Positivists, so far as 

 they accept the teachings of their master, roundly 

 assert, at any rate in words, that observation of 

 the mind is a thing inherently impossible in itself, 

 and that psychology is a chimera a phantasm 

 generated by the fermentation of the dregs of 

 theology. Nevertheless, if M. Comte had been 

 asked what he meant by " physiologic cerebrale," 

 except that which other people call " psychology "; 

 and how he knew anything about the functions of 

 the brain, except by that very " observation 

 interieure," which he declares to be an absurdity 

 it seems probable that he would have found it 

 hard to escape the admission, that, in vilipending 

 psychology, he had been propounding solemn 

 nonsense. 



It is assuredly one of Hume's greatest merits 

 that he clearly recognised the fact that philosophy 

 is based upon psychology; and that the inquiry 

 into the contents and the operations of the mind 



