380 BEVIEWS — THE VALIDITY OF CONSCIOUSNESS. 



this American publication might tempt us, but merely, by way of 

 note, to advert to certain statements of that distinguished writer 

 regarding the trustworthiness of consciousness : advanced with spe- 

 cial reference to the theory of sensitive perception ; but which, whe- 

 ther in their bearing on that doctrine, or in their application gene- 

 rally, seem to be open to grave objections. If we should be thought 

 to criticise too severely the .statements referred to, our excuse must 

 be the pre-eminence — the deserved pre-eminence — of the philoso- 

 pher by whom they are made. The mistakes of an ordinary writer 

 might be left unnoticed, or passed lightly over ; but should Sir AVil- 

 liam Hamilton really be in error in what he teaches on the funda- 

 mental question of the validity of consciousness, it is of the utmost 

 importance that his error should be pointed out. 



In his exposition of the "Philosophy of Common Sense," Sir 

 "William, after shewing that our knowledge is not all at second 

 hand, but that some at least of our cognitions must be immediate, 

 proceeds to answer the inquiry how these certify us of their veracity. 

 Is consciousness perfectly trustworthy ? 



" Limiting, therefore, our consideration to the question of authority : how, it is 

 asked, do these primary propositions— these fundamental facts, feelings, beliefs, 

 certify us of their own veracity? To this the only possible answer is, that as ele- 

 ments of our mental constitution — as the essential conditions of our knowledge — 

 they must by us be accepted as true. To suppose their falsehood is to suppose 

 that we are created capable of intelligence, in order to be made the victims of 

 delusion ; that God is a deceiver, and the root of our nature a lie. But such a 

 supposition, if gratuitous, is manifestly illegitimate. For, on the contrary, the 

 data of our original consciousness must, it is evident, in the first instance, be pre- 

 sumed true. It is only if proved false that their authority can, in consequence of 

 that proof ', be, in the second instance, disallowed." 



In another passage, after stating that, " though the veracity of 

 the primary convictions of consciousness must in the outset be ad- 

 mitted, it still remains competent to lead a proof that they are un- 

 deserving of credit," Sir "William continues : 



,l But how is this to be done? As the ultimate grounds of knowledge, these 

 convictions cannot be redargued from any higher knowledge ; and, as original be- 

 liefs, they are paramount in certainty to every derivative assurance. But they are 

 many; they are, in authority, co-ordinate ; and their testimony is clear and pre- 

 cise. It is therefore competent for us to view them in co-relation ; to compare 

 their declarations ; and to consider whether they contradict, and, by contradicting, 

 invalidate each other. This mutual contradiction is possible in two ways. (1.) It 

 may be that the primary data themselves are directly or immediately contradictory 

 of each other ; (2.) it may be that they are mediately or indirectly contradictory, 

 inasmuch as the consequences to which they necessarily lead, and for the truth or 



