thing but body, its real essence, or internal constitution, on which these qualities depend, can be nothing but the figure, size, and connexion of its solid parts; of neither of which having any distinct perception at all, can I have any idea of its essence, which is the cause that it has that particular shining yellowness, a greater weight than any thing I know of the same bulk, and a fitness to have its colour changed by the touch of quicksilver. If any one will say, that the real essence and internal constitution, on which these properties depend, is not the figure, size, and arrangement or connexion of its solid parts, but something else, called its particular form, I am farther from having any idea of its real essence than I was before: for I have an idea of figure, size, and situation of solid parts in general, though I have none of the particular figure, size, or putting together of parts, whereby the qualities above-mentioned are produced; which qualities I find in that particular parcel of matter that is on my finger, and not in another parcel of matter with which I cut the pen I write with. But when I am told that something besides the figure, size, and posture of the solid parts of that body, is its essence, something called substantial form; of that, I confess, I have no idea at all, but only of the sound form, which is far enough from an idea of its real essence or constitution. The like ignorance as I have of the real essence of this particular substance, I have also of the real essence of all other natural ones: of which essences, I confess, I have no distinct ideas at all; and I am apt to suppose others, when they examine their own knowledge, will find in themselves, in this one point, the same sort of ignorance.

$7. Now then, when men apply to this particular parcel of matter on my finger a general name already in use, and denominate it gold, do they not ordinarily, or are they not understood to give it that name as belonging to a particular species of bodies, having a real internal essence; by having of which essence this

particular substance comes to be of that species, and to be called by that name? If it be so, as it is plain it is, the name by which things are marked, as having that essence, must be referred primarily to that essence; and consequently the idea to which that name is given must be referred also to that essence, and be intended to represent it. Which essence since they who so use the names know not, their ideas of substances must be all inadequate in that respect, as not containing in them that real essence which the mind intends they should.

Ideas of substances, as

collections of their qualities, are all inadequate.

§ 8. Secondly, those who neglecting that useless supposition of unknown real essences, whereby they are distinguished, endeavour to copy the substances that exist in the world, by putting together the ideas of those sensible qualities which are found co-existing in them, though they come much nearer a likeness of them than those who imagine they know not what real specific essences; yet they arrive not at perfectly adequate ideas of those substances they would thus copy into their minds; nor do those copies exactly and fully contain all that is to be found in their archetypes. Because those qualities and powers of substances, whereof we make their complex ideas, are so many and various, that no man's complex idea contains them all. That our abstract ideas of substances do not contain in them all the simple ideas that are united in the things themselves it is evident, in that men do rarely put into their complex idea of any substance all the simple ideas they do know to exist in it. Because endeavouring to make the signification of their names. as clear, and as little cumbersome as they can, they make their specific ideas of the sorts of substance, for the most part, of a few of those simple ideas which are to be found in them: but these having no original precedency, or right to be put in, and make the specific idea more than others that are left out, it is plain

that both these ways our ideas of substances are deficient and inadequate. The simple ideas, whereof we make our complex ones of substances, are all of them (bating only the figure and bulk of some sorts) powers, which being relations to other substances, we can never be sure that we know all the powers that are in any one body, till we have tried what changes it is fitted to give to, or receive from, other substances, in their several ways of application: which being impossible to be tried upon any one body, much less upon all, it is impossible we should have adequate ideas of any substance made up of a collection of all its properties.

89. Whosoever first lighted on a parcel of that sort of substance we denote by the word gold, could not rationally take the bulk and figure he observed in that lump to depend on its real essence or internal constitution. Therefore those never went into his idea of that species of body; but its peculiar colour, perhaps, and weight, were the first he abstracted from it, to make the complex idea of that species. Which both are but powers; the one to affect our eyes after such a manner, and to produce in us that idea we call yellow; and the other to force upwards any other body of equal bulk, they being put into a pair of equal scales, one against another. Another, perhaps, added to these the ideas of fusibility and fixedness, two other passive powers, in relation to the operation of fire upon it; another, its ductility and solubility in aq. regia, two other powers relating to the operation of other bodies, in changing its outward figure, or separation of it into insensible parts. These, or part of these, put together, usually make the complex idea in men's minds of that sort of body we call gold.

§ 10. But no one, who hath considered the properties of bodies in general, or this sort in particular, can doubt that this called gold has infinite. other properties, not contained in that complex idea. Some, who

have examined this species more accurately, could, I believe, enumerate ten times as many properties in gold, all of them as inseparable from its internal constitution as its colour or weight: and it is probable, if any one knew all the properties that are by divers men known of this metal, there would be an hundred times as many ideas go to the complex idea of gold, as any one man yet has in his; and yet, perhaps, that not be the thousandth part of what is to be discovered in it. The changes which that one body is apt to receive, and make in other bodies, upon a due application, exceeding far not only what we know, but what we are apt to imagine. Which will not appear so much a paradox to any one who will but consider how far men are yet from knowing all the properties of that one, no very compound figure, al triangle; though it be no small number that are already by mathematicians discovered of it.

Ideas of substances, as collections of their qualities, are all inadequate.

§ 11. So that all our complex ideas of substances are imperfect and inadequate: which would be so also in mathematical figures, if we were to have our complex ideas of them only by collecting their properties in reference to other figures. How uncertain and imperfect would our ideas be of an ellipsis, if we had no other idea of it but some few of its properties! Whereas, having in our plain idea the whole essence of that figure, we from thence discover those properties, and demonstratively see how they flow, and are inseparable from it.

Simple ideas, εκτυπα, and adequate.

§ 12. Thus the mind has three sorts of abstract ideas or nominal essences:

First, simple ideas, which are exluta, or copies; but yet certainly adequate: because being intended to express nothing but the power in things to produce in the mind such a sensation, that sensation, when it is produced, cannot but be the effect of that power. So the paper I write on having the power in the light (I speak according to the common notion of

light) to produce in men the sensation which I call white, it cannot but be the effect of such a power, in something without the mind; since the mind has not the power to produce any such idea in itself, and being meant for nothing else but the effect of such a power, that simple idea is real and adequate; the sensation of white, in my mind, being the effect of that power which is in the paper to produce it, is perfectly ade quate to that power, or else that power duce a different idea.

would pro

Ideas of sub

stances are

exluma, inadequate.

§ 13. Secondly, the complex ideas of substances are ectypes, copies too; but not perfect ones, not adequate: which is very evident to the mind, in that it plainly perceives that whatever collection of simple ideas it makes of any substance that exists, it cannot be sure that it exactly answers all that are in that substance: since not having tried all the operations of all other substances upon it, and found all the alterations it would receive from, or cause in, other substances, it cannot have an exact adequate collection of all its active and passive capacities, and so not have an adequate complex idea of the powers of any substance existing, and its relations, which is that sort of complex idea of substances we have. And after all, if we would have, and actually had, in our complex idea, an exact collection of all the secondary qualities or powers of any substance, we should not yet thereby have an idea of the essence of that thing: for since the powers or qualities that are observable by us are not the real essence of that substance, but depend on it, and flow from it, any collection whatsoever of these qualities cannot be the real essence of that thing. Whereby it is plain, that our ideas of substances are not adequate, are not what the mind intends them to be. Besides, a man has no idea of substance in neral, nor knows what substance is in itself. §14. Thirdly, complex ideas of modes and relations are originals and archetypes; modes and

Ideas of

ge