verse, we are ignorant of the several powers, efficacies, and ways of operation, whereby the effects we daily see are produced. These are hid from us in some things, by being too remote; in others, by being too minute.

When we consider the vast distance of the known and visible parts of the world, and the reasons we have to think that what lies within our ken is but a small part of the immense universe; we shall then discover a huge abyss of ignorance. What are the particular fabrics of the great masses of matter, which make up the whole stupendous frame of corporeal beings, how far they are extended, and what is their motion, and how continued, and what influence they have on one another, are contemplations that at first glimpse our thoughts lose themselves in. If we confine our thoughts to this little canton, I mean this system of our sun, and the grosser masses of matter that visibly move about it; what several sorts of vegetables, animals, and intellectual corporeal beings, infinitely different from those of our little spot of earth, may probably be in other planets, to the knowlege 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 sensation or reflection, to convey their certain ideas into our minds !

There are other bodies in the universe, no less concealed from us by their minuteness. These insensible corpuscles being the active parts of matter, and the great instruments of nature, on which depend all their secondary qualities and operations, our want of precise distinct ideas of their primary qualities keeps us in incurable ignorance of what we desire to know about them. Did we know the mechanical affections of rhubarb and opium, we might as easily account for their operations of purging and causing sleep, as a watchmaker can for the motions of his watch. The

dissolving of silver in aquafortis, or gold in aquaregia, and not vice versa, would be then, perhaps, no more difficult to know, than it is to a smith to understand why the turning of one key will open a lock, and not the turning of another. But whilst we are destitute of senses, 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 operations; nor can we be assured about them any farther, than some few trials we make are able to reach but whether they will succeed again another time, we cannot be certain. This hinders our certain knowlege of universal truths concerning natural bodies; and our reason carries us herein very little beyond particular matter of fact.

And therefore I am apt to doubt, that how far soever human industry may advance useful and experimental philosophy in physical things, yet scientifical will still be out of our reach; because we want perfect and adequate ideas of those very bodies which are nearest to us, and most under our command.

This at first sight shows us how disproportionate our knowlege is to the whole extent, even of material beings to which, if we add the consideration of that infinite number of spirits that may be, and probably are, which are yet more remote from our knowlege, whereof we have no cognisance; we shall find this cause of ignorance conceal from us, in an impenetrable obscurity, almost the whole intellectual world: a greater, certainly, and a more beautiful world than the material. For, bating some very few ideas of spirit we get from our own mind by reflection, and from thence the best we can collect, of the Father of all spirits, the Author of them, and us, and all things, we have no certain information, so much as of the existence of other spirits, but by revelation: much less have we distinct ideas of their different natures, states,

powers, and several constitutions, wherein they agree or differ one from another, and from us; and, therefore, in what concerns their different species and properties, we are under an absolute ignorance.

The second cause of ignorance is the want of discoverable connexion between those ideas we have: where we want that, we are utterly incapable of universal and certain knowlege; and are, as in the former case, left only to observation and experiment. Thus the mechanical affections of bodies, having no affinity at all with the ideas they produce in us, we can have no distinct knowlege of such operations beyond our experience; and can reason no otherwise about them, than as the effects or appointment of an infinitely wise Agent, which perfectly surpass our comprehensions.

The operation of our minds on our bodies is as unconceivable. How any thought should produce a motion in body, is as remote from the nature of our ideas, as how any body should produce any thought in the mind. That it is so, if experience did not convince us, the consideration of the things themselves would never be able in the least to discover to us.

In some of our ideas there are certain relations, habitudes, and connexions, so visibly included in the nature of the ideas themselves, that we cannot conceive them separable from them by any power whatsoever in these only we are capable of certain and universal knowlege. Thus the idea of a right-lined triangle necessarily carries with it an equality of its angles to two right ones. But the coherence and continuity of the parts of matter, the production of sensation in us, of colors and sounds, &c. by impulse and motion, being such wherein we can discover no natural connexion with any ideas we have, we cannot but ascribe them to the arbitrary will and good pleasure of the wise Architect. The things that we observe constantly to proceed regularly, we may conclude do act by a law set them; but yet by a

law that we know not; whereby, though causes work steadily, and effects flow constantly from them, yet their connexions and dependences being not discoverable in our ideas, we can have but experimental knowlege of them. Several effects come every day within the notice of our senses, of which we have so far sensitive knowlege. But the causes, manner, and certainty of their production, we must, for the foregoing reasons, be content to be ignorant of. In these we can go no farther than particular experience informs us of matter of fact, and by analogy guess what effects the like bodies are on other trials like to produce. But as to perfect science of natural bodies (not to mention spiritual beings) we are, I think, so far from being capable of any such thing, that I conclude it lost labor to seek after it.

The third cause of ignorance is our want of tracing those ideas we have, or may have; and finding out those intermediate ideas which may show us what habitude of agreement or disagreement they may have one with another: and thus many are ignorant of mathematical truths, for want of application in inquiring, examining, and by due ways comparing those ideas.

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Hitherto we have examined the extent of our knowlege, in respect of the several sorts of beings that are. There is another extent of it, in respect of universality, which will also deserve to be considered; and in this regard our knowlege follows the nature of our ideas. If the ideas are abstract, whose agreement or disagreement we perceive, our knowlege is universal. For what is known of such general ideas will be true of every particular thing in which that essence, that is, that abstract idea, is to be found : and what is once known of such ideas, will be perpetually and for ever true. So that, as to all general knowlege, we must search and find it only in our own minds: and it is only the examining of our own

ideas that furnishes us with that. Truths belonging to essences of things (that is, to abstract ideas) are eternal, and are to be found out by the contemplation only of those essences, as the existence of things is to be known only from experience. But I shall say more of this in the following chapters, where I shall speak of general and real knowlege.

CHAPTER IV.

Of the Reality of our Knowlege.

I doubt not but my reader, by this time, may be apt to think that I have been all this while only building a castle in the air; and be ready to objectIf it be true, that all knowlege lies only in the per, ception of the agreement or disagreement of our own ideas, the visions of an enthusiast, and the reasonings of a sober man will be equally certain: it is no matter how things are; so a man observe but the agreement of his own imaginations, and talk conformably, it is all truth, all certainty. That an harpy is not a centaur, is by this way as certain knowlege, and as much truth, as that a square is not a circle. But of what use is all, this knowlege of men's own imaginations to a man that inquires after the reality of things?

To which I answer, that if our knowlege of our ideas should terminate in them, and reach no farther, where there is something farther intended, our most serious thoughts would be of little more use than the reveries of a crazy brain. But I hope, before I have done, to make it evident, that this way of certainty by the knowlege of our own ideas goes a little farther than bare imagination; and that all the certainty of general truths a man has, lies in nothing else but this knowlege of our ideas.

It is evident that the mind knows not things immediately, but by the intervention of the ideas it has of