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THUS the idea of heat and cold, light and darkness, white and black, motion and reft, are equally clear and pofitive ideas in the mind; though perhaps fome of the causes which produce them are barely privations in those -fubjects from whence our fenfes derive thofe ideas. These the understanding, in its view of them, confiders all as diftinct pofitive ideas, without taking notice of the causes that produce them; which is an inquiry not belonging to the idea, as it is in the understanding, but to the nature of the things existing without us. Thefe are two very different things, and carefully to be diftinguished; it being one thing to perceive and know the idea of white or black, and quite another to examine what kind of particles they must be, and how ranged in the fuperficies, to make any object appear white or black.

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A PAINTER or dyer, who never inquired into their causes, hath the ideas of white and black, and other colours, as clearly, perfectly, and diftinctly in his understanding, and perhaps more diftinctly, than the philofopher, who hath bufied himself in confidering their natures, and thinks he knows how far either of them is in its caufe pofitive or privative; and the idea of black is no lefs pofitive in his mind, than that of white, however the caufe of that color in the external object may be only a privation.

§ 4.

If it were the defign of my prefent undertaking, to inquire into the natural caufes and manner of perception, I fhould offer this as a reason why a privative caufe might, in some cases at least, produce a pofitive idea; viz. That all fenfation, being produced in us only by different degrees and modes of motion in our animal' fpirits, va riously agitated by external objects, the abatement of any former motion must as neceffarily produce a new fenfation, as the variation or increase of it; and fo introduce a new idea, which depends only on a different motion of the animal fpirits in that organ. P

Vol. I.

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BUT whether this be fo or no, I will not here determine, but appeal to every one's own experience, whether the shadow of a man, though it confifts of nothing but the absence of light (and the more the abfence of light is, the more difcernable is the shadow) does not, when a man looks on it, caufe as clear and pofitive an idea in his mind, as a man himself, though covered over with clear fun-fhine? and the picture of a fhadow is a pofitive thing. Indeed we have negative names, which ftand not directly for pofitive ideas, but for their absence, fuch as infipid, filence, nihil, &c. ; which words denote pofitive ideas; v. g. tafte, found, being, with a fignificátion of their absence.

§ 6. Pofitive Ideas from privative Caufes.

AND thus one may truly be faid to fee darkness. For, fuppofing a hole perfectly dark, from whence no light is reflected, it is certain one may fee the figure of it, or it may be painted; or whether the ink I write with makes any other idea, is a question. The privative causes I have here affigned of pofitive ideas, are according to the common opinion; but in truth it will be hard to deter mine, whether there be really any ideas from a privative cause, till it be determined, whether reft be any more, a privation than motion.

7. Ideas in the Mind, Qualities in Bodies. To discover the nature of our ideas the better, and tọ discourse of them intelligibly, it will be convenient to distinguish them as they are ideas or perceptions in our minds, and as they are modifications of matter in the bodies that caufe fuch perceptions in us; that fo we may not think (as perhaps ufually is done) that they are exactly the images and refemblances of fomething inherent in the subject; most of those of fenfation being in the mind no more the likeness of fomething exifting without us, than the names that stand for them are the likeness of our ideas, which yet upon hearing they are apt to excite in us.

§ 8.

WHATSOEVER the mind perceives in itself, or is the im

mediate object of perception, thought, or understanding, that I call idea; and the power to produce any idea in our mind, I call quality of the fubject wherein that power is. Thus a fnow-ball having the power to produce in us the ideas of white, cold, and round, the powers to produce those ideas in us, as they are in the fnow7 ball, I call qualities; and as they are fenfations or perceptions in our understandings, I call them ideas which ideas, if I fpeak of fometimes, as in the things themfelves, I would be understood to mean thofe qualities irv the objects which produce them in us.

9. Primary Qualities:

QUALITIES thus confidered in bodies are, first, fuch as are utterly infeparable from the body, in what estate soever it be; fuch as in all the alterations and changes it fuffers, all the force can be used upon it, it constantly keeps; and fuch as fenfe conftantly finds in every particle of matter which has bulk enough to be perceived and the mind finds infeparable from every particle of matter, though lefs than to make itself fingly be perceived by our fenfes, v. g. Take a grain of wheat, divide it into two parts, each part has ftill folidity, extenfon, figure, and mobility; divide it again, and it retains ftill the fame qualities; and fo divide it on, till the parts become infenfible, they must retain ftill each of them all thofe qualities. For divifion (which is all that a mill, or peftle, or any other body, does upon another, in reducing it to infenfible parts) can never take away either folidity, extenfion, figure, or mobility, from any body, but only makes two or more diftinct feparate maffes of matter, of that which was but one before; all which diftinct maffes, reckoned as fo many diftinct bodies, after divifion make a certain number. Thefe I call original or primary qualities of body, which I think we may obferve to produce fimple ideas in us, viz. folidity, extenfion, figure, motion, or reft, and

number.

§ 10. Secondary Qualities.

2dly, SUCH qualities which in truth are nothing in the objects themselves, but powers to produce various fen-

fations in us by their primary qualities, i. e. by the bulk, figure, texture, and motion of their infenfible parts, as colours, founds, taftes, &c. thefe I call fecondary quali ties. To these might be added a third fort, which are allowed to be barely powers, though they are as much real qualities in the fubject, as thofe which I, to comply, with the common way of speaking, call qualities, but, for diftinction, fecondary qualities. For the power in fire to produce a new colour, or confiftency, in wax or clay, by its primary qualities, is as much a quality in fire, as the power it has to produce in me a new idea or fenfation ofwarmth or burning, which I felt not before, by the fame primary qualities, viz. the bulk, texture, and motion of its infenfible parts.

§ 11. How primary Qualities produce their Ideas. THE next thing to be confidered, is, How bodies produce ideas in us; and that is manifeftly by impulfe, the only way which we can conceive bodies to operate in.

§ 12.

If, then, external objects be not united to our minds, when they produce ideas therein, and yet we perceive thefe original qualities in fuch of them as fingly fall under our fenfes, it is evident, that fome motion must be thence continued by our nerves or animal fpirits, by fome parts of our bodies, to the brain, or the feat of fenfation, there to produce in our minds the particular ideas we have of them. And fince the extenfion, figure, number, and motion of bodies of an obfervable bignefs, may be perceived at a distance by the fight, it is evident fome fingly imperceptible bodies must come from them to the eyes, and thereby convey to the brain fome motion, which produces thefe ideas which we have of them in us. 13. How Secondary.

AFTER the fame manner that the ideas of thefe original qualities are produced in us, we may conceive, that the ideas of fecondary qualities are also produced, viz. by the operation of infenfible particles on our fenfes. For it being manifeft, that there are bodies, and good ftore of bodies, each whereof are fo finall, that we cannot, by any of our fenfes, difcover either their bulk, figure or mo

tion, as is evident in the particles of the air and water,, and others extremely fmaller than thofe, perhaps as much smaller than the particles of air and water, as the particles of air and water are smaller than peafe or hailftones let us fuppofe at prefent, that the different motions and figures, bulk and number, of fuch particles, affecting the feveral organs of our fenfes, produce in us those different fenfations, which we have from the colours and smells of bodies; v. g. that a violet, by the impulfe of fuch infenfible particles of matter of peculiar figures and bulks, and in different decrees and mod-ifications of their motions, caufes the ideas of the blue colour, and fweet cent of that flower, to be produced in our minds; it being no more impoffible to conceive that God. fhould annex fuch ideas to fuch motions, with which they have no fimilitude, than that he should annex the idea of pain to the motion of a piece of steel. dividing our flesh, with which that ideahath no refem-blance.

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WHAT I have faid concerning colours and fmells, may be: understood alfe of taftes and founds, and other the like fenfible qualities; which, whatever reality we, by miftake attribute to them, are in truth nothing in the objects themfelves, but powers to produce various fenfations in us, and depend on thofe primary qualities, viz.. bulk, figure, texture and motion of parts; as I have faid. § 15. Ideas of primary Qualities are resemblances; of

Secondary, not..

FROM whence I think it easy to draw this obfervation that the ideas of primary qualities of bodies, are refemblances of them, and their patterns do really exift in the bodies themselves; but the ideas, produced in us by thefe fecondary qualities, have no refemblance of them at all. There is nothing like our ideas exifting in the bodies themselves. They are in the bodies, we denominate from them, only a power to produce those fenfations in us; and what is fweet, blue, or warm in idea, is but the certain bulk, figure, and motion of the infenfible partss in the bodies themfelves, which we call fo

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