these particular circumstances in our minds, then we either demonstrate the proposition of the general and abstract idea of a triangle, or of no idea at all; for after the particulars are omitted, or not attended to by the mind, the only idea remaining must be a general one. Farther, that on which I am willing to rest the whole controversy, is the following remark, _viz._, that without the general idea of a line or triangle, there could be no particular one; that is, no idea of any one line or triangle, as of the same form, or as any way related to any other, so that there could be no common measure or line to connect any of our thoughts or reasoning together into a general conclusion. For to take the former instance as the most simple. When we speak of any particular extension, it is evident that we understand something which is not particular. Besides what is peculiar to it, it must have something which is not peculiar to it, but general, to merit the common appellation. Berkeley says, ‘An idea which in itself is particular, becomes general, by being made to represent or stand for all other particular ideas _of the same sort_.’ I do request that the import of these last words may be attended to. Do they suggest any idea or none; if they mean any thing, it must be something more than the particular ideas which are said to be of the same sort, _i.e._ some general notion of them. But this will involve all the absurdities of abstraction. If there is any thing in the mind besides these particular ideas themselves—any thing that compares or contrasts them, that refers to this or that belief, this comparison or classifying can be nothing but a perception of a general nature in which these things agree, or the general resemblance which the mind perceives between the several impressions. If there is no such comparison or perception of resemblance, or idea of abstract qualities, then there can be no idea answering to the words ‘of the same sort;’ but these particular ideas will be left standing by themselves, absolutely unconnected. As far as our ideas are merely particular, _i.e._ are negations of other ideas, so far they must be perfectly distinct from each other: there can be nothing between them to blend or associate them together. Each separate idea would be surrounded with a _chevaux de frise_ of its own, in a state of irreconcilable antipathy to every other idea, and the fair form of nature would present nothing but a number of discordant atoms. A particular line would no more represent another line, than it would represent a point: one colour could no more resemble another colour, or suggest its idea, than it could that of a sound, or a smell; there could be no clue to make us class different shades of the same colour under one general name, any more than the most opposite: one triangle would be as distinct from another, as from a square or a cube, and so through the whole system of art and nature. There must be a mutual leaning, a