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ders it, as well as figure, in the minutest particle of matter that can exift, and finds it infeparably inherent in body, wherever or however modified.

§2. Solidity fills Space.

THIS is the idea belongs to body, whereby we conceive it to fill space; the idea of which filling of space is, that where we imagine any space taken up by a folid fubftance, we conceive it fo to poffefs it, that it excludes all other folid fubftances, and will for ever hinder any two other bodies, that move towards one another in a ftraight line, from coming to touch one another, unless it removes from between them in a line not parallel to that which they move in. This idea of it the bodies which we ordinarily handle fufficiently furnish us with. §3. Diftinct from Space.

THIS refiftance, whereby it keeps other bodies out of the space which it poffeffes, is fo great, that no force, how great foever, can furmount it. All the bodies in the world preffing a drop of water on all fides, will never be able to overcome the refiftance which it will make, as foft as it is, to their approaching one another, till it be removed out of their way; whereby our idea of folidity is diftinguished both from pure space, which is capable neither of refiftance nor motion, and from the ordinary idea of hardness; for a man may conceive two bodies at a distance, fo as they may approach one an other, without touching or difplacing any folid thing till their fuperficies come to meet; whereby I think* we have the clear idea of fpace without folidity. For (not to go fo far as annihilation of any particular body) I ask, whether a man cannot have the idea of the motion of one fingle body alone, without any other fucceeding immediately into its place? I think it is evident he can, the idea of motion in one body no more including the idea of motion in another, than the idea of a fquare figure in one body includes the idea of a fquare figure in another. I do not afk, whether bodies do so exift, that the motion of one body cannot really be without the motion of another; to determine this either way, is to beg the question for or against a vacuum: But my queftion is, whether one cannot have the idea of one

body moved whilft others are at reft? And I think this no one will deny. If fo, then the place it deferted gives us the idea of pure fpace without folidity, whereinto another body may enter, without either refiftance. or protrusion of any thing. When the fucker in a pump is drawn, the fpace it filled in the tube is certainly the fame, whether any other body follows the motion of the fucker or no; nor does it imply a contradiction, that upon the motion of one body, another, that is only contiguous to it, fhould not follow it. The neceflity of fuch a motion is built only on the fuppofition that the word is full, but not on the distinct ideas of space and folidity, which are as different as refiftance and not refiftance, protrufion and not protrufion. And that men have ideas of space without body, their very difputes about a vacuum plainly demonftrate, as is fhowed in another place.

4. From Hardness.

SOLIDITY is hereby alfo differenced from hardness, in that folidity confifts in repletion, and fo an utter exclufion of other bodies out of the space it poffeffes; but hardness, in a firm cohefion of the parts of matter, making up maffes of a fenfible bulk, fo that the whole does not easily change its figure: And indeed hard and foft are names that we give to things, only in relation to the conftitutions of our own bodies, that being generally called hard by us which will put us to pain. fooner than change figure by the preffure of any part of our bodies; and that, on the contrary, foft, which changes the fituation of its parts upon an eafy and unpainful touch.

But this difficulty of changing the fituation of the fenfible parts amongst themselves, or of the figure of the whole, gives no more folidity to the hardest body in the world than to the fofteft; nor is an adamant one jot more folid than water; for though the two flat fides of two pieces of marble will more easily approach each other, between which there is nothing but water or air, than if there be a diamond between them, yet it is not that the parts of the diamond are more folid than those

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of water, or refift more, but because the parts of water being more eafily feparable from each other, they will by a fide-motion be more eafily removed, and give way to the approach of the two pieces of marble. But if they could be kept from making place by that fidemotion, they would eternally hinder the approach of these two pieces of marble as much as the diamond, and it would be as impoffible by any force to furmount their resistance, as to furmount the refiftance of the parts of a diamond. The fofteft body in the world will as invincibly refift the coming together of any two other bodies, if it be not put out of the way, but remain between them, as the hardeft that can be found or imagined. He that fhall fill a yielding foft body well with air or water, will quickly find its refiftance; and he that thinks that nothing but bodies that are hard can keep his hands from approaching one another, may be pleased to make a trial, with the air inclofed in a football. The experiment, I have been told, was made at Florence with a hollow globe of gold filled with water, and exactly clofed, farther fhows the folidity of so soft a body as water; for the golden globe thus filled being put into a prefs, which was driven by the extreme force of fcrews, the water made itself way through the pores of that very close metal, and finding no room for a nearer approach of its particles within, got to the outfide, where it rofe like a dew, and fo fell in drops, before the fides of the globe could be made to yield to the violent compreffion of the engine that fqueezed it.

§ 5. On Solidity depends Impulfe, Refiflance, and Pro

trufion.

By this idea of folidity, is the extension of body diftinguifhed from the extenfion of fpace; the extenfion of body being nothing but the cohefion or continuity of folid, feparable, moveable parts; and the extenfion of fpace, the continuity of unfolid, infeparable, and immoveable parts. Upon the folidity of body alfo depends their mutual impulse, resistance, and protrufion. Of pure fpace, then, and folidity, there are feveral (amongst which I confefs myfelf one) who perfuade themfelves

they have clear and distinct ideas; and that they can think on fpace, without any thing in it that refifts, or is protruded by body. This is the idea of pure fpace,. which they think they have as clear as any idea they can have of the extenfion of body, the idea of the distance between the oppofite parts of a concave fuperficies, being equally as clear without as with the idea of any folid parts between; and, on the other fide, they perfuade themselves, that they have, diftinct from that of pure fpace, the idea of fomething that fills fpace, that can be protruded by the impulfe of other bodies, or refift their motion. If there be others that have not these two ideas diftinct, but confound them, and make but one of them, I know not how men, who have the fame idea under different names, or different ideas under the fame name, can in that cafe talk with one another, any more than a man, who, not being blind or deaf, has diftinct ideas of the colour of scarlet, and the found of a trumpet, could difcourfe concerning fcarlet colour with the blind man I mentioned in another place, who fancied that the idea of scarlet was like the found of a trumpet.

§ 6. What it is.

Ir any one afks me, What this folidity is? I fend him to his fenfes to inform him: Let him put a flint or a foot-ball between his hands, and then endeavour to join them, and he will know. If he thinks this not a fufficient explication of folidity, what it is, and where it confifts, I promife to tell him what it is, and wherein it confifts, when he tells me what thinking is, or wherein it confifts, or explains to me what extenfion or motion is, which perhaps feems much eafier. The fimple ideas we have, are fuch as experience teaches them us; but if beyond that, we endeavour by words to make them clearer in the mind, we shall fucceed no better than if we went about to clear up the darkness of a blind man's mind by talking, and to difcourfe unto him the ideas of light and colours. The reafon of this I fhall fhow in another place.

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CHAP. V.

OF SIMPLE IDEAS OF DIVERS SENSES.

HE ideas we get by more than one fenfe, are of Space, or extenfion, figure, reft, and motion; for thefe make perceivable impreffions, both on the eyes and touch; and we can receive and convey into our minds the ideas of the extenfion, figure, motion, and reft of bodies, both by feeing and feeling. But having occafion to speak more at large of these in another place, I here only enumerate them.

CHAP. VI.

OF SIMPLE IDEAS OF REFLECTION.

1. Simple Ideas are the Operations of the Mind about its other Ideas.

HE mind receiving the ideas mentioned in the

foregoing chapters from without, when it turns its view inward upon itself, and obferves its own actions about thofe ideas it has, takes from thence other ideas, which are as capable to be the objects of its contemplation as any of those it received from foreign things.

2. The Idea of Perception, and Idea of Willing, ave have from Reflection.

THE two great and principal actions of the mind, which are most frequently confidered, and which are fo frequent, that every one that pleases may take notice of them in himself, are these two:

Perception, or thinking, and
Volition, or willing.

The power of thinking is called the underflanding, and the power of volition is called the will, and thele two powers or abilities in the mind are denominated faculties. Of fome of the modes of thefe fimple ideas of election,

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