77. But, say you, though it be granted that there is no thoughtless support of extension, and the other qualities or accidents which we perceive, yet there may perhaps be some inert, unperceiving substance or _substratum_ of some other qualities, as incomprehensible to us as colours are to a man born blind, because we have not a sense adapted to them. But, if we had a new sense, we should possibly no more doubt of _their_ existence than a blind man made to see does of the existence of light and colours.—I answer, first, if what you mean by the word _Matter_ be only the unknown support of unknown qualities, it is no matter whether there is such a thing or no, since it no way concerns us. And I do not see the advantage there is in disputing about what we know not _what_, and we know not _why_. 78. But, secondly, if we had a new sense, it could only furnish us with new ideas or sensations; and then we should have the same reason against _their_ existing in an unperceiving substance that has been already offered with relation to figure, motion, colour, and the like. _Qualities_, as hath been shewn, are nothing else but _sensations_ or _ideas_, which exist only in a mind perceiving them; and this is true not only of the ideas we are acquainted with at present, but likewise of all possible ideas whatsoever(658). ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ 79. But you will insist, What if I have no reason to believe the existence of Matter? what if I cannot assign any use to it, or explain anything by it, or even conceive what is meant by that word? yet still it is no contradiction to say that Matter _exists_, and that this Matter is _in general_ a _substance_, or _occasion of ideas_; though indeed to go about to unfold the meaning, or adhere to any particular explication of those words may be attended with great difficulties.—I answer, when words are used without a meaning, you may put them together as you please, without danger of running into a contradiction. You may say, for example, that _twice two_ is equal to _seven_; so long as you declare you do not take the words of that proposition in their usual acceptation, but for marks of you know not what. And, by the same reason, you may say there is an inert thoughtless substance without accidents, which is the occasion of our ideas. And we shall understand just as much by one proposition as the other. ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐