corporeal beings, infinitely different from those of our little spot of earth, may there probably be in the other planets, to the knowledge of which, even of their outward figures and parts, we can no way attain, whilst we are confined to this earth; there being no natural means, either by fenfation or reflection, to convey their certain ideas into our minds? They are out of the reach of thofe inlets of all our knowledge; and what forts of furniture and inhabitants those manfions contain in them, we cannot fo much as guefs, much lefs have clear and distinct ideas of them.

$25. Because of their Minuteness.

Ir a great, nay, far the greatest part of the feveral ranks of bodies in the universe escape our notice by their remotenefs, there are others that are no lefs concealed from us by their minuteness. Thefe infenfible corpufcles being the active parts of matter, and the great inftruments of nature, on which depend not only all their fecondary qualities, but also most of their natural operations; our want of precife, diftinct ideas of their primary qualities, keeps us in an incurable ignorance of what we deure to know about them. I doubt not but if we could difcover the figure, fize, texture, and motion of the minute conftituent parts of any two bodies, we fhould know without trial feveral of their operations one upon another, as we do now the properties of a fquare or a triangle. Did we know the mechanical affections of the particles of rhubarb, hemlock, opium, and a man, as a watchinaker does thofe of a watch, whereby it performs its operations, and of a file, which by rubbing on them will alter the figure of any of the wheels; we should be able to tell beforehand, that rhubarb will purge, bemlock kill, and opium make a man fleep, as well as a watchmaker can, that a little piece of paper laid on the balance will keep the watch from going, till it be removed; or that fome fmall part of it being rubbed by a file, the machine would quite lofe its motion, and the watch go no more. The diffolving of filver in aqua fortis, and gold in aqua regia, and not vice

verfa, would be then perhaps no more difficult to know, than it is to a faith to underfland why the turning of one key will open a lock, and not the turning of another. But whilft we are deftitute of fenfes acute enough to discover the minute particles of bodies, and to give us ideas of their mechanical affections, we must be content to be ignorant of their properties and ways of operation; nor can we be affured about them any farther than fome few trials we make are able to reach : But whether they will fucceed again another time, we cannot be certain. This hinders our certain knowledge of univerfal truths concerning natural bodies: and our reafon carries us herein very little beyond particular matter of fact.

§ 20. Hence n Science of Bodies.

AND therefore I am apt to doubt, that how far foever human industry may advance ufeful and experimental philofophy in physical things, fcientifical will still be out of our reach; because we want perfect and adequate ideas of thofe very bodies which are nearest to us, and most under our command. Those which we have ranked into claffes under names, and we think ourfelves beft acquainted with, we have but very im perfect and incomplete ideas of. Dittinet ideas of the feveral forts of bodies that fall under the examination of our fenfes, perhaps we may have; but adequate ideas, I fufpect, we have not of any one amongst them. And though the former of these will ferve us for common ufe and discourse, yet whilft we want the latter, we are not capable of fcientifical knowledge, nor fhall ever be able to difcover general, inftructive, unqueftionable truths concerning them. Certainty and demonftration are things we must not in these matters pretend to. By the colour, figure, tafte, and fmell, and other fenfible qualities, we have as clear and diftinct ideas of fage and hemlock, as we have of a circle and a triangle; but having no ideas of the particular primary qualities of the minute parts of either of thefe plants, nor of other bodies which we would apply them to, we cannot tell what effects they will pro

duce; nor when we fee thofe effects, can we so much as guefs, much lefs know their manner of production. Thus having no ideas of the particular mechanical affections of the minute parts of bodies that are within our view and reach, we are ignorant of their conftitutions, powers, and operations; and of bodies more remote, we are yet more ignorant, not knowing fo much as their very outward fhapes, or the fenfible and groffer parts of their conftitutions.

$27. Much lefs of Spirits.

This, at firit fight, will how us how difproportionate our knowledge is to the whole extent even of material beings; to which if we add the confideration of that infinite number of fpirits that may be, and probably are, which are yet more remote from our knowledge, whereof we have no cognifance, nor can frame to our felves any distinct ideas of their feveral ranks and forts, we fhall find this caufe of ignorance conceal from us, in an impenetrable obfcurity, almof the whole intellectual world; a greater certainly, and more beautiful world than the material. For bating fome very few, and thofe, if I may fo call them, fuperficial ideas of fpirit, which by reflection we get of our own, and from thence the best we can collect of the Father of all fpirits, the eternal independent Au thor of them and us and all things; we have no certain information, fo much as of the existence of other fpirits, but by revelation. Angels of all forts are naturally beyond our difcovery: And all thofe intelligences, whereof it is likely there are more orders than of corporeal fubftances, are things whereof our na tural faculties give us no certain account at all. That there are minds and thinking beings in other men as well as himself, every man has a reafon, from their words and actions, to be fatisfied; and the knowledge of his own mind cannot fuffer a man that confiders, to be ignorant that there is a God. But that there are degrees of fpiritual beings between us and the great God, who is there that by his own fearch and ability can come to know? Much lefs have we dif

tinct ideas of their different natures, conditions, states, powers, and several conftitutions, wherein they agree or differ from one another, and from us; and there. fore in what concerns their different fpecies and properties, we are under an abfolute ignorance.

28. Secondly, Want of a difcoverable Connection between Ideas we have.

SECONDLY, What a small part of the fubftantial beings that are in the univerfe, the want of ideas leave open to our knowledge, we have feen. In the next place, another caufe of ignorance, of no lefs moment, is a want of a difcoverable connection between thofe ideas we have; for wherever we want that, we are utterly incapable of univerfal and certain knowledge; and are, as in the former cafe, left only to obfervation and experiment; which, how narrow and confined it is, how far from general knowledge, we need not be told. I fhall give fome few inftances of this cause of our ignorance, and fo leave it. It is evident that the bulk, figure, and motion of feveral bodies about us, produce in us feveral fenfations, as of colours, founds, taftes, fmells, pleasure and pain, &c. These mechanical affections of bodies having no affinity at all with thofe ideas they produce in us (there being no conceivable connection between any impulfe of any fort of body, and any perception of a colour, or fmell, which we find in our minds), we can have no distinct knowledge of fuch operations beyond our experience, and can reafon no otherwife about them, than as effects produced by the appointment of an infinitely wife Agent, which perfectly iurpafs our comprehenfions. As the ideas of fentible fecondary qualities which we have in our minds, can by us be no way deduced from bodily caufes, nor any correfpondence or connection be found between them and thofe primary qualities which (experience fhows us) produce them in us; fo, on the other fide, the operation of our minds upon our bodies is as unconceivable. How any thought fhould produce a motion in body, is as remote from the nature of our ideas, as how any bo

dy fhould produce any thought in the mind. That it is fo, if experience did not convince us, the confideration of the things themselves would never be able in the least to discover to us. Thefe, and the like, though they have a conftant and regular connection, in the ordinary courfe of things, yet that connection being not difcoverable in the ideas themfelves, which appearing to have no neceffary dependence one on another, we can attribute their connection to nothing else but the arbitrary determination of that all-wife Agent, who has made them to be, and to operate as they do, in a way wholly above our weak understandings to conceive.

$29. Inftances.

IN fome of our ideas there are certain relations, habitudes, and connections, fo vifibly included in the nature of the ideas themselves, that we cannot conceive them feparable from them by any power whatsoever; and in thefe only we are capable of certain and univerfal knowledge. Thus the idea of a right-lined triangle neceffarily carries with it an equality of its angles to two right ones. Nor can we conceive this relation, this connection of these two ideas, to be poffibly mutable, or to depend on any arbitrary power, which of choice made it thus, or could make it otherwife. But the coherence and continuity of the parts of matter; the production of fenfation in us of colours and founds, &c. by impulfe and motion; nay, the original rules and communication of motion being fuch, wherein we can difcover no natural connection with any ideas we have, we cannot but afcribe them to the arbitrary will and good pleasure of the wife Architect. I need not, I think, here mention the refurrection of the dead, the future ftate of this globe of earth, and fuch other things, which are by every one acknowledged to depend wholly on the determi nation of a free Agent. The things that, as far as our obfervation reaches, we conflantly find to proceed regularly, we may conclude do act by a law fet them, but yet by a law that we know not; whereby, though