364 



ON ANCIENT AND MODERN SKEPTICS. 



first principle he had laid down for the regulation of his conduct, he was 

 determined to doubt of the evidence of the senses, excepting so far as they 

 could bring- proof of their correctness. But what proof had the senses to 

 offer ? The very notion of a proof, as I took leave to observe in our last lec- 

 ture, consists in our obtaining a fact or an idea possessing a closer agreement 

 or connexion with the thing to be proved than the fact or idea that the mind 

 first perceives or is able to lay hold of. But what ideas can more closely 

 agree or be more closely connected with an external world than the ideas 

 produced by the senses, by which alone the mind perceives such world to 

 exist? These are ideas of identity, of self-agreement; and, consequently, 

 ideas which, like that of consciousness, it is neither possible to doubt of or 

 to prove. They form, for the most part, a branch of intuitive knowledge, 

 and we are compelled to believe whether we will or not. 



I say for the most jiart, for I am now speaking of the common effect of ex- 

 ternal objects upon the senses, and upon the mental organ. I am ready to 

 admit that, under particular circumstances, the ideas they excite may not be 

 perfectly clear : we may be at too great a distance from the object, or the 

 sense of sight, smell, taste, or touch may be morbidly or accidentally obtuse ; 

 but in all these cases a sound mind is just as conscious of having ideas that 

 are not clear, as it is, under other circumstances, of having distinct ideas. 

 There is no imposition whatever: the mind equally knows that it has cer- 

 tain knowledge in the latter instance, and that it has uncertain knowledge in 

 the former. I mean, if it will exert itself to know by the exercise of its own 

 activity; for otherwise it may as well mistake in ideas that originate from 

 itself as in those that originate from the senses. And in the case of its being 

 conscious of an imperfect or indistinct idea, excited by one of the senses, 

 what is the step it pursues 1 That which it uniformly pursues in every other 

 case of imperfect knowledge : it calls in the aid of an intermediate idea by the 

 exercise of another sense that is more closely connected or more clearly 

 agrees with the idea that raises the question, and the faculty of the judgment 

 determines, as in every otiier case. And here the knowledge, as I have 

 already hinted at on a former occasion, loses indeed its intuitive character, 

 and assumes, for the most part, the demonstrative. 



It was impossible, therefore, for Des Cartes to obtain any proofs whatever ; 

 and it being the very preamble of his system that his doubts should remain 

 unless he could remove them by proofs, the only device that seemed to afford 

 him a loophole to escape from his dilemma was an appeal to the veracity of 

 the Creator. God, he asserted, has imprinted on the mind innate ideas of 

 himself and of an external world; and tiiough the senses offer no demonstra- 

 tion of such a world, it is completely furnished to us by these internal ideas : 

 the senses, indeed, may deceive, but God can be no deceiver. And hence 

 what appears to exist around us does exist. 



The existence of an external world, therefore, in the Cartesian philosophy 

 is doubtful, so far as depends upon the senses ; for the testimony they offer 

 is in itself doubtful. And hence it is not upon the evidence of our eyes and 

 our hands, and our taste, smell, and hearing, that we are to believe that there 

 is any body or any thing without us, but on the truth of those innate ideas 

 of a something without us which are supposed to be imprinted on the mind, 

 in connexion with the veracity of the Creator who has imprinted them. 



But here another stumbling-block occurred to the progress of our philo- 

 sophical castle-builder; and that was, the difficulty of determining, in regard 

 to the number and extent of these innate ideas. His friends Gassendi and 

 Hobbes openly denied that there were any such ideas whatever, and put him 

 upon his proofs, by which the whole system would be to be commenced again 

 from its foundation; while Malebranche, one of the most zealous of all the 

 disciples of Des Cartes, at the same time that he contended for the general 

 doctrine of innate ideas, confessed that he had some doubts whether they 

 extended to the existence of the world without us, or to any thing but a 

 knowledge of God and of our own being. 



Although, in his opinion, M. Des Cartes has proved the existence of bodv 



