Union, which gives Umbrage to the Objection, is not made by Contact.

But perhaps the Union of Bodies is still Mechanically folvable, tho' not by Contact only, yet by Rest fuperadded to it, as fome, or the Preffure of the Atmosphere, as others contend.

But granting that either, or both of thefe come up to a full Solution; nevertheless the Senfual Prejudice of Contact is remov'd; which thefe Additional Suppofitions prove, is not able to folve the Phenomenon: And indeed if Contact alone were fufficient, there cou'd be no Reafon given, why all Bodies, of what Superficies foever, did not in fome degree unite upon Touch, as Iron doth with the Magneti

But the Addition of Rest and Pressure may, perhaps, feem to be only fubfervient to Contact in this Union; the latter to bring the Parts together, and the former to continue their Juxta-pofition: Let us therefore examin their Capacity, as Causes to produce this Effect: And of them both I may pronounce, That they are already demonftrated equally incapable, with Con tact; as will eafily appear by recollecting, that That Part of the Body B in Reft, which has no Motion communicated to it by A, according to this Suppofition, moves of it felf: And as to the Pressure of the Atmo

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Atmosphere: Is it poffible, for that to make a Body move, without being it self the Impellent Cause? Which it cannot be in the Progreffive Motion of Bodies, because it is fuppos'd to unite the Parts of them by an equal Preffure on all fides; and it is clear, that this Preffure must move that Part of the Body B which is not mov'd by A, if it unites the Parts of B; for by virtue of Union they move together: Or can the Pressure be fuch an Impellent Cause, as to make a Body continue Motion in a different Line from that, in which it was receiv'd?

Again, as to Rest uniting the Parts of Matter, Des Cartes very dexterously avoids the infuperable Difficulty attending it, by telling us we can imagin no other Cement but Rest; and then putting the Question, Quid enim est Glutinum illud? non Subftantia,quia cum Particule

Princ. Phil. 1. 2. §. 55.

ifte fint Subftantia, nulla ratio est cur per aliam Subftantiam potius, quam per feipfas jungerentur, &c. For it may be very difficult to imagin what Subftance, befides themselves, can unite them; (tho' by the way, the Power of Uniting is involv'd in the Power of Moving Matter, and therefore we are not fo much at a Lofs for another Subftance) and yet it may be impoffible to conceive, that they can unite

them

themselves by Rest. An heap of Sand may be as perfectly at Rest, as a piece of Marble; but the Parts do not alike cohere: It's true, the Air may be always in Motion, in the Interstices left by the Globules of Sand; but fo is that, or fubtler Matter, in the Pores of Marble; and while there is no fuch Motion in the other, as to change the Place and Situation of one Grain, with refpect to another, the Sand is as much at Reft, and ought to be as coherent, as the Marble.

The Preffure of the Atmosphere, is still a weaker Subterfuge: For what is it that fo unites the Parts of this Elaftical_Fluid? Are all Bodies in the Universe that are united, furrounded with an Atmosphere? And what then furrounds that, to make its Particles act with united Force upon them? Or is this only defign'd for a Piece of Sublunary Philofophy? Truly it will not bear carrying any farther.

And now I think it appears, that this Union is above all Mechanical Solution. I defire the Confequence of this may be confider'd: If we cannot conceive how Material Subftances, which lye nearest to our Understanding, tho' not level with it, are united; in vain do we endeavour to conceive, or complain for want of Conception, how an Immaterial Subftance is united

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united to Material. There are but Three Sorts of Union we can suppose of Substances; that of Two Material, that of Two Immaterial Subftances, or laftly the Union between both; and if we do not comprehend the first, which yet we find to be Matter of Fact; our not being able to comprehend either of the other, is no Objection to Arguments in themselves conclufive for their Union. We have fome Idea of Substances Separately in Action; of Material, in the Action of Motion; and of Immaterial, in the Action of Thought; but we have no Idea of any Substance in Action, purely by its Dependence on another Created Substance. Our Faculties, in their utmost Extent, fall fhort of this Knowledge; our Creator having conceal'd from us the Dependence of Subftances on each other, as much as he has done the Dependence of them all on Himself.

By confidering this, we are prepar'd to answer that Objection, fo much in the Mouth of our Adverfaries: Material cannot obstruct the Operations of Immaterial Subftance; how then comes it to pass, that our Thoughts depend fo much upon the Temperament of our Bodies? That the Soul, as other things Immaterial, can move and penetrate the Body, we grant; but that it thou'd, therefore, exert its Operations,

without any Obftruction from the Body, we fee no Reafon : For this is the fame thing as to say, it thinks, without any Inftrumental Affiftance of the Body, which we do not suppose it does in this State; and if fuch determinate Corporeal Motions, do neceffarily precede, or accompany fuch determinate Thoughts, no wonder there is a fit Difpofition requir'd, in those Farts of the Body, in order to perform their own Mctions. The Soul may very poffibly have an Original Power in it felf to think, independently on all Matter; tho' many of the most confiderable Ancient Philofophers held a Corporeal Vehicle, neccffary to the Operations of all Created Spirits; fo far were they from efteeming the Union of Soul and Body an Abfurdity: But be that as it has pleas'd God; we are fure that our felves do not Think, as Immaterial Beings only; but as Immaterial Beings, united to a Part of the Material World: And therefore a Quality, which belongs only to one Part of our Nature, and cou'd never affect the other, feparately confider'd, may affect our whole Nature; which is now become One, fo far as it is conftituted and compounded of them both.

And now I hope we have, without venturing beyond our Stretch, which wou'd have render'd our Endeavours ineffectual