Page:The Works of John Locke - 1823 - vol 01.djvu/178

102  and that general indetermined idea of something is, by the abstraction of the mind, derived also from the simple ideas of sensation and reflection: and thus the mind, from the positive, simple ideas got by sensation and reflection, comes to the general relative idea of substance, which, without these positive simple ideas, it would never have.

This your lordship (without giving by retail all the particular steps of the mind in this business) has well expressed in this more familiar way: "We find we can have no true conception of any modes or accidents, but we must conceive a substratum, or subject, wherein they are; since it is a repugnancy to our conceptions of things, that modes or accidents should subsist by themselves."

Hence your lordship calls it the rational idea of substance: and says, "I grant that by sensation and reflection we come to know the powers and properties of things; but our reason is satisfied that there must be something beyond these, because it is impossible that they should subsist by themselves:" so that if this be that which your lordship means by the rational idea of substance, I see nothing there is in it against what I have said, that it is founded on simple ideas of sensation or reflection, and that it is a very obscure idea.

Your lordship's conclusion from your foregoing words is, "and so we may be certain of some things which we have not by those ideas;" which is a proposition, whose precise meaning your lordship will forgive me, if I profess, as it stands there, I do not understand. For it is uncertain to me, whether your lordship means, we may certainly know the existence of something, which we have not by those ideas; or certainly know the distinct properties of something, which we have not by those ideas; or certainly know the truth of some proposition, which we have not by those ideas: for to be certain of something may signify either of these. But in which soever of these it be meant, I do not see how I am concerned in it. to his hand; but can do nothing towards the making the least particle of new matter, or destroying one atom of what is already in being. The same inability will every one find in himself, who shall go about to fashion in his understanding any simple idea, not received in by his senses from external objects, or by reflection from the operations of his own mind about them. I would have any one try to fancy any taste, which had never affected his palate; or frame the idea of a scent he had never smelt: and when he can do this, I will also conclude that a blind man hath ideas of colours, and a deaf man true distinct notions of sounds.