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to be; are made use of in the probation of propositions, wherein are words standing for complex ideas; v. g. man, horse, gold, virtue; there they are of infinite danger, and most commonly make men receive and retain falsehood for manifest truth, and uncertainty for demonstration: upon which follow error, obstinacy, and all the mischiefs that can happen from wrong reasoning. The reason whereof is not that these principles are less true, or of less force in proving propositions made of terms standing for complex ideas, than where the propositions are about simple ideas; but because men mistake generally, thinking that where the same terms are preserved, the propositions are about the same things, though the ideas they stand for are in truth different: therefore these maxims are made use of to support those, which in sound and appearance are contradictory propositions; as is clear in the demonstrations above-mentioned about a vacuum. So that whilst men take words for things, as usually they do, these maxims may and do commonly serve to prove contradictory propositions: as shall yet be farther made manifest.

Instance in man.

§ 16. For instance, let man be that concerning which you would by these first principles demonstrate any thing, and we shall see, that so far as demonstration is by these principles, it is only verbal, and gives us no certain universal true proposition or knowledge of any being existing without us. First, a child having framed the idea of a man, it is probable that his idea is just like that picture, which the painter makes of the visible appearances joined together; and such a complication of ideas together in his understanding makes up the single complex idea which he calls man, whereof white or flesh-colour in England being one, the child can demonstrate to you that a negro is not a man, because white colour was one of the constant simple ideas of the complex idea he calls man: and therefore he can demonstrate by the principle, it is im

possible for the same thing to be, and not to be, that a negro is not a man; the foundation of his certainty being not that universal proposition, which perhaps he never heard nor thought of, but the clear distinct perception he hath of his own simple ideas of black and white, which he cannot be persuaded to take, nor can ever mistake one for another, whether he knows that maxim or no: and to this child, or any one who hath such an idea, which he calls man, can you never demonstrate that a man hath a soul, because his idea of man includes no such notion or idea in it. And therefore, to him, the principle of what is, is, proves not this matter; but it depends upon collection and observation, by which he is to make his complex idea called man.

§ 17. Secondly, another that hath gone farther in framing and collecting the idea he calls man and to the outward shape adds laughter and rational discourse, may demonstrate that infants and changelings are no men, by this maxim, it is impossible for the same thing to be, and not to be; and I have discoursed with very rational men, who have actually denied that they are men.

§ 18. Thirdly, perhaps another makes up the complex idea which he calls man only out of the ideas of body in general, and the powers of language and reason, and leaves out the shape wholly: this man is able to demonstrate, that a man may have no hands, but be quadrupes, neither of those being included in his idea of man; and in whatever body or shape he found speech and reason joined, that was a man: because having a clear knowledge of such a complex idea, it is certain that what is, is.

§ 19. So that, if rightly considered, I think we may say, that where our ideas are determined in our minds, and have annexed to them by us known and steady names under those settled determinations, there is little, need or no use at all of these maxims, to prove the agreement

Little use of ims in proofs where we have clear and distinct ideas.

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or disagreement of any of them. He that cannot discern the truth or falsehood of such propositions, without the help of these and the like maxims, will not be helped by these maxims to do it: since he cannot be supposed to know the truth of these maxims themselves without proof, if he cannot know the truth of others without proof, which are as self-evident as these. Upon this ground it is, that intuitive knowledge neither requires nor admits any proof, one part of it more than another. He that will suppose it does, takes away the foundation of all knowledge and certainty and he that needs any proof to make him certain, and give his assent to this proposition, that two are equal to two, will also have need of a proof to make him admit, that what is, is. He that needs a probation to convince him, that two are not three, that white is not black, that a triangle is not a circle, &c. or any other two determined distinct ideas are not one and the same, will need also a demonstration to convince him, that it is impossible for the same thing to be, and not to be.

Their use dangerous where our ideas are confused.

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$20. And as these maxims are of little use where we have determined ideas, so they are, as I have showed, of dangerous use where our ideas are not determined

and where we use words that are not annexed to determined ideas, but such as are of a loose and wandering signification, sometimes standing for one, and sometimes for another idea: from which follow mistake and error, which these maxims (brought as proofs to establish propositions, wherein the terms stand for undetermined ideas) do by their authority confirm and rivet.

CHAPTER VIII.

Of Trifling Propositions.

Some propositions bring no increase to our knowledge.

Such are, As, first, identical propositions.

$1. WHETHER the maxims treated of in the foregoing chapter be of that use to real knowledge as is generally supposed, I leave to be considered. This, I think, may confidently be affirmed, that there are universal propositions, which though they be certainly true, yet they add no light to our understandings, bring no increase to our knowledge. 2. First, all purely identical propositions. These obviously, and at first blush, appear to contain no instruction in them. For when we affirm the said term of itself, whether it be barely verbal, or whether it contains any clear and real idea, it shows us nothing but what we must certainly know before, whether such a proposition be either made by or proposed to us. Indeed, that most general one, what is, is, may serve sometimes to show a man the absurdity he is guilty of, when by circumlocution, or equivocal terms, he would, in particular instances, deny the same thing of itself; because nobody will so openly bid defiance to common sense, as to affirm visible and direct contradictions in plain words; or if he does, a man is excused if he breaks off any farther discourse with him. But yet, I think, I may say, that neither that received maxim, nor any other identical proposition teaches us any thing: and though in such kind of propositions this great and magnified maxim, boasted to be the foundation of demonstration, may be and often is made use of to confirm them; yet all it proves amounts to no more than this, that the same word may with great certainty be affirmed of itself, without any doubt of

the truth of any such proposition; and let me add also, without any real knowledge.

§ 3. For at this rate, any very ignorant person, who can but make a proposition, and knows what he means when he says ay or no, may make a million of propositions, of whose truths he may be infallibly certain, and yet not know one thing in the world thereby ; v. g. what is a soul, is a soul; or a soul is a soul; a spirit is a spirit; a fetiche is a fetiche, &c. These all being equivalent to this proposition, viz. what is, is, i. e. what hath existence, hath existence; or who hath a soul, hath a soul. What is this more than trifling with words? It is but like a monkey shifting his oyster from one hand to the other; and had he but words, might, no doubt, have said, "oyster in right hand is subject, and oyster in left hand is predicate:" and so might have made a self-evident proposition of oyster, i. e. oyster is oyster; and yet, with all this, not have been one whit the wiser or more knowing: and that way of handling the matter would much at one have satisfied the monkey's hunger, or a man's understanding; and they would have improved in knowledge and bulk together.

I know there are some who, because identical propositions are self-evident, show a great concern for them, and think they do great service to philosophy by crying them up, as if in them was contained all knowledge, and the understanding were led into all truth by them only. I grant as forwardly as any one, that they are all true and self-evident. I grant farther, that the foundation of all our knowledge lies in the faculty we have of perceiving the same idea to be the same, and of discerning it from those that are different, as I have shown in the foregoing chapter. But how that vindicates the making use of identical propositions, for the improvement of knowledge, from the imputation of trifling, I do not see. Let any one repeat, as often as he pleases, that the will is the will, or lay what stress on it he thinks fit; of what use is this, and an infinite the like propositions, for the en

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