10 Philosophy of the Human Mind. 



ledged that the adoption of the principles which 

 they maintained ought not to affect the practice 

 of men, who must ever act as if they were known 

 to be false: an argument, one would imagine, it- 

 self, of strong presumptive force, against all their 

 plausible reasonings. But however the doctrines 

 inculcated by these subtle disputants might have 

 opposed their own feelings, or shocked the minds 

 of others, it is certain they contributed much to 

 promote that speculative philosophy, the tendency 

 of which is to strike at the root of all knowledge, 

 and all belief. 



On observing the sceptical conclusions which 

 Berkeley and Hume had drawn from the old 

 theory of perception, as it had been taught, in sub- 

 stance, by all writers, from Pythagoras down to 

 their time, some philosophers of Great-Britain 

 were led, about the middle of the eighteenth cen- 

 tury, to call this theory in question. If it were as- 

 sumed as true that we perceive, not external ob- 

 jects themselves, but only the ideas in our minds,, 

 they saw no method of avoiding the consequences 

 which had been so daringly admitted. They, 

 therefore, denied the grand doctrine on which 

 the whole superstructure they wished to oppose 

 w T as built j and endeavoured to show, that, as the 

 premises were gratuitously assumed and false, so 

 the conclusions deduced from them were absurd 

 and impossible. This controversy, doubtless, de- 

 serves to be considered among the most memorable 

 of the age 5 and if the principles and reasonings of 

 certain modern metaphysicians of North-Britain, to 

 the publication of which this controversy has given 

 rise, be regarded as just, they certainly form the 

 most important accession which the philosophy of 

 mind has received since the time of Mr. Locke. 



At the head of these British philosophers stands 

 Dr. Reid, who first, in his Inquiry into the Human 



