there are at the same time direct and evident proofs of it.  But for the existence of Matter there is not one proof, and far more numerous and insurmountable objections lie against it.  But where are those mighty difficulties you insist on?  Alas! you know not where or what they are; something which may possibly occur hereafter.  If this be a sufficient pretence for withholding your full assent, you should never yield it to any proposition, how free soever from exceptions, how clearly and solidly soever demonstrated.

HYL.  You have satisfied me, Philonous.

Phil.  But, to arm you against all future objections, do but consider:  That which bears equally hard on two contradictory opinions can be proof against neither.  Whenever, therefore, any difficulty occurs, try if you can find a solution for it on the hypothesis of the Materialists.  Be not deceived by words; but sound your own thoughts.  And in case you cannot conceive it easier by the help of materialism, it is plain it can be no objection against immaterialism.  Had you proceeded all along by this rule, you would probably have spared yourself abundance of trouble in objecting; since of all your difficulties I challenge you to shew one that is explained by Matter:  nay, which is not more unintelligible with than without that supposition; and consequently makes rather against than for it.  You should consider, in each particular, whether the difficulty arises from the non-existence of matter.  If it doth not, you might as well argue from the infinite divisibility of extension against the Divine prescience, as from such a difficulty against immaterialism.  And yet, upon recollection, I believe you will find this to have been often, if not always, the case.  You should likewise take heed not to argue on a PETITIO PRINCIPII.  One is apt to say—­The unknown substances ought to be esteemed real things, rather than the ideas in our minds:  and who can tell but the unthinking external substance may concur, as a cause or instrument, in the productions of our ideas?  But is not this proceeding on a supposition that there are such external substances?  And to suppose this, is it not begging the question?  But, above all things, you should beware of imposing on yourself by that vulgar sophism which is called ignoratio ELENCHI.  You talked often as if you thought I maintained the non-existence of Sensible Things.  Whereas in truth no one can be more thoroughly assured of their existence than I am.  And it is you who doubt; I should have said, positively deny it.  Everything that is seen, felt, heard, or any way perceived by the senses, is, on the principles I embrace, a real being; but not on yours.  Remember, the Matter you contend for is an Unknown Somewhat (if indeed it may be termed somewhat), which is quite stripped of all sensible qualities, and can neither be perceived by sense, nor apprehended by the mind.  Remember I say, that