own minds, and it is only the examining of our own ideas that furnishes us with that. Truths belonging to Essences of things (that is, to Abstract Ideas) are eternal, and are to be found out by the contemplation only of those Essences; as the existence of things is to be known only from Experience.

CHAPTER IV.

OF THE REALITY OF HUMAN KNOWLEDGE.

Objection. Knowledge placed in ideas may be all bare vision.—I doubt not but my reader by this time may be ready to say, "If it be true, that all Knowledge lies only in the perception of the agreement or disagreement of our own ideas, the visions of an enthusiast, and the reasonings of a sober man, will be equally certain. If there be any difference between them, the advantage will be on the warm-headed man's side, as having the more ideas, and the more lively: [whereas] it is this alone [that] gives a value to our reasonings, and [a] preference to one man's knowledge over another's,— that it is of things as they really are, and not of dreams and fancies."

Answer. Not so where ideas agree with things.-To which I answer-That if our Knowledge of our ideas terminate in them, and reach no farther where there is something farther intended, our most serious thoughts will be of little more use than the reveries of a crazy brain; and the truths built thereon of no more weight than the

discourse of a man who sees things clearly in a dream, and with great assurance utters them. But I hope to make it evident, that this way of certainty-by the Knowledge of our own ideas-goes a little farther than bare imagination; and I believe it will appear, that all the certainty of General Truths [which] a man has lies in nothing else.

It is evident the mind knows not things immediately, but only by the intervention of the ideas [which] it has of them. Our Knowledge therefore is real only so far as there is a conformity between our ideas and the reality of things. There [are] two sorts of ideas that we may be assured agree with things.

As all simple ideas do.-First are Simple ideas: which ideas are not fictions of our fancies, but the natural and regular productions of things [existing] without us, really operating upon us; and so carry with them all the conformity which is intended, or which our state requires.

All complex ideas, except of substances.-Secondly, all Complex ideas, except those of Substances, being archetypes of the mind's own making, not intended to be the copies of anything, nor referred to the existence of anything, as to their originals, cannot want any conformity necessary to real Knowledge. For that which is not designed to represent anything but itself can never be capable of a wrong representation, nor mislead us from the true apprehension of anything by its unlikeness to it; and such, excepting those of Substances, are all our Complex ideas.

Hence the reality of mathematical knowledge.-I doubt

not but it will be easily granted that the Knowledge we have of mathematical truths is not only certain, but real, Knowledge; and not the bare empty vision of vain, insignificant chimeras of the brain; and yet, if we will consider, we shall find that it is only of our own ideas. The mathematician considers the truth and properties belonging to a rectangle or circle, only as they are in idea in his own mind. For it is possible he never found either of the[se figures] existing mathematically —i. e. precisely true [to his conception of it]—in his life. But yet the knowledge he has of any truths or properties belonging to a circle, or any other mathematical figure, is nevertheless true and certain even of real things existing: because real things are no farther concerned, nor intended to be meant by any such propositions, than as things really agree to those archetypes in his mind. Is it true of the idea of a triangle, that its three angles are equal to two right ones? It is true also of a triangle wherever it really exists. Whatever other figure exists that is not exactly answerable to the idea of a triangle in his mind is not at all concerned in that proposition. And therefore he is certain [that] all his Knowledge concerning such ideas is real Knowledge.

And of Moral.-In the same manner, the truth and certainty of moral discourses abstract from the lives of men and the existence of those virtues in the world whereof they treat: nor are Tully's Offices less true because there is nobody in the world that exactly practises his rules, and lives up to that pattern of a virtuous man

*

That is, 'form general propositions independently of.'-ED.

which he has given us, and which existed nowhere when he wrote but in idea. If it be true in speculation, —i. e. in idea,—that murder deserves death, it will also be true in reality of any action that exists conformable to that idea of murder. As for other actions, the truth of that proposition concerns them not. And thus it is of all other species of things which have no other Essences but those ideas which are in the minds of men. And hence it follows that Moral Knowledge is as capable of real certainty as Mathematics. For, Certainty being but the perception of the agreement or disagreement of our ideas, and Demonstration nothing but the perception of such agreement by the intervention of other ideas or mediums-our moral ideas as well as mathematical being archetypes themselves, and so adequate and complete ideas,-all the agreement or disagreement which we shall find in them will produce Real Knowledge, as well as in mathematical figures.

For the attaining of Knowledge and certainty, it is requisite that we have determined ideas; and to make our knowledge real, it is requisite-that the ideas answer their archetypes.

Nor will it be less true or certain because moral ideas are of our own making and naming. But it will here be said, that "if Moral Knowledge be placed in the contemplation of our own Moral Ideas, and those, as other Modes, be of our own making, what strange notions will there be of 'justice' and 'temperance!' What confusion of virtues and vices, if every one may make what ideas of them he pleases!" [Answer]-No confusion or disorder in the things themselves, nor [in] the reasonings about

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them; no more than (in mathematics) there would be a disturbance in the demonstration, or a change in the properties of figures and their relations one to another, if a man should make a triangle' with four corners, or a 'trapezium' with four right angles: that is, change the names of the figures, and call that by one name which mathematicians called ordinarily by another. The change of the name by the impropriety of speech will at first disturb him who knows not what idea it stands for: but as soon as the figure is drawn, the consequences and demonstration are plain and clear. Just the same is it in moral knowledge; let a man have the idea of taking from others, without their consent, what their honest industry has possessed them of, and call this 'justice,' if he please. He that takes the name here without the idea put to it will be mistaken, by joining another idea of his own to that name: but strip the idea of that name, or take it such as it is in the speaker's mind, and the same things will agree to it as if you called it 'injustice.' Indeed, wrong names in moral discourses breed usually more disorder, because they are not so easily rectified as in mathematics, where the figure once drawn and seen makes the name useless and of no force.

Misnaming disturbs not the certainty of the knowledge. One thing more we are to take notice ofthat where GOD, or any lawmaker, has defined any Moral Names, there they have made the Essence of that species to which that Name belongs; and there it is not safe to apply or use them otherwise: but in other cases it is bare impropriety of speech to apply them contrary to the common usage of the country. But yet even this