252 THE METAPHYSICS OF SENSATION 



istic side of Descartes' philosophy, that the Free- 

 thinkers had given to its sceptical side,, and the 

 Newtonians to its mechanical side. 



Berkeley faced the problem boldly. He said 

 to the materialists: "You tell me that all the 

 phenomena of nature are resolvable into matter 

 and its affections. I assent to your statement, 

 and now I put to you the further question, ' What 

 is matter?' In answering this question you shall 

 be bound by your own conditions; and I demand, 

 in the terms of the Cartesian axiom, that in turn 

 you give your assent only to such conclusions as 

 are perfectly clear and obvious/' 



It is this great argument which is worked out 

 in the " Treatise concerning the Principles of 

 Human Knowledge/' and in those "Dialogues 

 between Hylas and Philonous," which rank among 

 the most exquisite examples of English style, as 

 well as among the subtlest of metaphysical 

 writings; and the final conclusion of which 

 is summed up in a passage remarkable alike 

 for literary beauty, and for calm audacity of 

 statement. 



" Some truths there are so near and obvious to the mind 

 that a man need only open his eyes to see them. Such I 

 take this important one to be, viz., that all the choir of 

 heaven and furniture of the earth in a word, all those 

 bodies which compose the mighty frame of the world have 

 not any substance without a mind ; that their being is to be 

 perceived or known ; that consequently, so long as they are 

 not actually perceived by me, or do not exist in my mind or 

 that of any other created spirit, they must either have no 



