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Maxims, if Care be not taken in the Ufe of words, may prove Contradictions.

ONE thing farther, I think, it may not be amifs to obferve concerning thefe general maxims, that they are fo far from improving or establishing our minds in true knowledge, that if our notions be wrong, loose, or unfteady, and we refign up our thoughts to the found of words, rather than fix them on settled determined ideas of things; I fay these general maxims will ferve to confirm us in mistakes, and in fuch a way of ufe of words, which is most common, will ferve to prove contradictions; v. g. he that, with Des Cartes, fhall frame in his mind an idea of what he calls body, to be nothing but extenfion, may easily de. monstrate that there is no vacuum, i. e. no fpace void of body, by this maxim, what is, is; for the idea to which he annexes the name body being bare exten. fion, his knowledge that space cannot be without body is certain; for he knows his own idea of ex. tenfion clearly and diftinctly, and knows that it is what it is, and not another idea, though it be called by these three names, extenfion, body, Space, which three words, ftanding for one and the fame idea, may no doubt, with the fame evidence and certainty, be affirmed one of another, as each of itself; and it is as certain, that whilst I ufe them all to ftand for one and the fame idea, this predication is as true and identical in its fignification, that space is body, as this predication is true and identical, that body is body, both in fignification and found.

13. Inftance in Vacuum.

BUT if another thall come, and make to himself another idea different from Des Cartes's, of the thing, which yet, with Des Cartes, he calls by the fame name body, and make his idea, which he expreffes by the word body to be of a thing that hath both extenfion and folidity together; he will as eafily demonftrate, that there may be a vacuum or space without a body, as Des Cartes demonftrated the contrary; becaufe the idea to which he gives the name Space be

ing barely the fimple one of extenfion, and the idea to which he gives the name body being the complex idea of extenfion and refiftibility, or folidity, together in the fame fubject, these two ideas are not exactly one and the fame, but in the understanding as diftinė as the ideas of one and two, white and black, or as of corporeity and humanity, if I may use those barbarous terms; and therefore the predication of them in our minds, or in words standing for them, is not identical, but the negation of them one of another; viz. this propofition, extenfion or Space is not body, is as true and evidently certain as this maxim, it is impoffible for the fame thing to be, and not to be, can make any propofition.

§14. They prove not the Exiftence of Things with

out us.

BUT yet, though both these propofitions (as you see) may be equally demonftrated, viz. that there may be a vacuum, and that there cannot be a vacuum by these two certain principles, viz. what is, is, and the fame thing cannot be, and be; yet neither of thefe principles will ferve to prove to us, that any, or what bodies do exift; for that we are left to our fenfes to discover to us as far as they can; thofe univerfal and felf-evident principles being only our conflant, clear, and diftinct knowledge of our own ideas, more general or comprehenfive, can affure us of nothing that passes without the mind; their certainty is founded only upon the knowledge we have of each idea by itself, and of its diftinction from others, about which we cannot be mistaken whiift they are in our minds, though we may and often are mistaken when we retain the names without the ideas, or use them confufedly fometimes for one, and fometimes for another idea; in which cafes the force of thefe axioms, reaching only to the found, and not the fignification of the words, ferves only to lead us into confufion, mistake, and error. It is to fhow men, that these maxims, however cried up for the great guards of truth, will not fecure them from error in a carelefs loose use of

Book IV. their words, that I have made this remark. In all that is here fuggefted concerning the little ufe for the improvement of knowledge, or dangerous ufe in undetermined ideas, I have been far enough from faying or intending they should be laid afide, as fome have been too forward to charge me. I affirm them to be truths, felf-evident truths, and fo cannot be laid afide. As far as their influence will reach, it is in vain to endeavour, nor would I attempt to abridge it; but yet, without any injury to truth or knowledge, I may have reason to think their use is not anfwerable to the great ftrefs which feems to be laid on them, and I may warn men not to make an ill use of them, for the con firming themselves in errors.

15. Their Application dangerous about complex

Ideas.

BUT let them be of what ufe they will in verbal prepofitions, they cannot discover or prove to us the leaf? knowledge of the nature of fubftances, as they are found and exift without us, any farther than grounded on experience; and though the confequence of these two propofitions, called principles, be very clear, and their ufe not dangerous or hurtful, in the probation of fuch things wherein there is no need at all of them for proof, but fuch as are clear by themfelves without them, viz. where our ideas are determined, and known by the names that ftand for them; yet when thefe principles, viz. what is, is, and it is impoffible for the fame thing to be, and not to be, are made ufe of in the probation of propofitions, wherein are words ftanding for complex ideas, v. g. man, horfe, gold, virtue, there they are of infinite danger, and moit commonly make men receive and retain falfehood for manifest truth, and uncertainty for demonftration; upon which follows error, obftinacy, and all the mifchiefs that can happen for wrong reafoning; the rea fon whereof is not that these principles are lefs true, or of lefs force in proving propofitions made of terms ftanding for complex ideas, than where the pro; ofitions are about fimple ideas; but because men mistake

generally, thinking that where the fame terms are preferved, the propofitions are about the fame things, though the ideas they ftand for are in truth different; therefore these maxims are made use of to support those, which in found and appearance are contradictory propofitions; as is clear in the demonftrations above-mentioned about a vacuum. So that whilst men take words for things, as ufually they do, these maxims may and do commonly ferve to prove contradictory propofitions, as fhall yet be farther made manifelt.

16. Inftance in Man.

FOR inftance; let man be that concerning which you would by these first principles demonftrate any thing, and we shall fee, that fo far as demonftration is by these principles, it is only verbal, and gives us no certain univerfal true propofition, 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 fingle 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 fimple ideas of the complex idea he calls man: and therefore he can demonftrate by the principle, it is impoffible for the fame thing to be, and not to be, that a negro is not a man; the foundation of his certainty being not that univerfal propofition, which perhaps he never heard nor thought of, but the clear diftinct perception he hath of his own fimple ideas of black and white, which he cannot be perfuaded 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 fuch an idea, which he calls man, can you never demonftrate that a man hath a foul, becaufe his idea of man includes no fuch notion or idea in it; and therefore to him the principle of what is, is, proves not this

:

Book IV. matter; but it depends upon collection and obfervation, by which he is to make his complex idea called 6 17.

man.

SECONDLY, another that hath gone farther in framing and collecting the idea he calls man, and to the outward shape adds laughter and rational difcourfe, may demonstrate that infants and changelings are no men, by this maxim, it is impoffible for the fame thing to be, and not to be: and I have difcourfed with very ration. al 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 fhape wholly. This man is able to demonstrate, that a man may have no hands, but be quadrupes, neither of thofe being included in his idea and in whatever body or fhape he found Speech and reafn joined, that was a man; because having a clear knowledge of fuch a complex idea, it is certain that what is, is.

of man;

$ 19. Little Ufe of thefe Maxims in Proofs where we have clear and distinct Ideas.

So that, if rightly confidered, I think we may fay, that where our ideas are determined in our minds, and have annexed to them by us known and steady names under thofe fettled determinations, there is little need or no use at all of thefe maxims, to prove the agreement or difagreement of any of them. He that cannot difcern the truth or falfehood of fuch prop fi tions, without the help of these and the like maxims, will not be helped by thefe maxims to do it; fince he cannot be fuppofed to know the truth of these maxims themselves without proof, if he cannot know the truth of others without proof, which are as felf-evident as thefe. Upon this ground it is that intuitive knowledge neither requires nor admits any proof, one part of it more than another. He that will fuppofe it does, takes away the foundation of all knowledge and cer

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