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heavy, fusible body, I call gold, be malleable or no; which experience (which way ever it prove in that particular body I examine) makes me not certain that it is so in all, or any other yellow, heavy, fusible bodies, but that which I have tried. Because it is no consequence one way or the other from my complex idea; the necessity or inconsistence of malleability hath no visible connexion with the combination of that colour, weight, and fusibility in any body. What i have said here of the nominal essence of gold, supposed to consist of a body of such a determinate colour, weight, and fusibility, will hold true if malleableness, fixedness, and solubility in aqua regia be added to it. Our reasonings from these ideas will carry us but a little way in the certain discovery of the other properties in those masses of matter wherein all these are to be found. Because the other properties of such bodies depending not on these, but on that unknown real essence on which these also depend, we cannot by them discover the rest; we can go no farther than the simple ideas of our nominal essence will carry us, which is very little beyond themselves; and so afford us but very sparingly any certain, universal, and useful truths. For upon trial having found that particular piece (and all others of that colour, weight, and fusibility that I ever tried) malleable, that also makes now perhaps a part of my complex idea, part of my nominal essence of gold: whereby though I make my complex idea, to which I affix the name gold, to consist of more simple ideas than before; yet still, it not containing the real essence of any species of bodies, it helps me not certainly to know (I say to know, perhaps it may to. conjecture) the other remaining properties of that body, farther than they have a visible connexion with some or all of the simple ideas that make up my nominal essence. For example, I cannot be certain from this complex idea whether gold be fixed or no; because, as before, there is no necessary connexion or inconsistence to be dis
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covered betwixt a complex idea of a body yellow, heavy, fusible, malleable,-betwixt these, I say, and fixedness; so that I may certainly know, that in whatsoever body these are found, there fixedness is sure to be. Here again for assurance I must apply myself to experience; as far as that reaches I may have certain knowledge, but no farther.
$ 10. I deny not but a man, accustomed
to rational and regular experiments, shall procure us
be able to see farther into the nature of nience, not
bodies, and guess righter at their yet unscience,
known properties, than one that is a stranger to them: but yet, as I have said, this is but judgment and opinion, not knowledge and certainty. This way of getting and improving our knowledge in substances only by experience and history, which is all that the weakness of our faculties in this state of mediocrity which we are in in this world can attain to, makes me suspect that natural philosophy is not capable of being made a science. We are able, I imagine, to reach very little general knowledge concerning the species of bodies, and their several properties. Experiments and historical observations we may have, from which we may draw advantages of ease and health, and thereby increase our stock of conveniencies for this life; but beyond this I fear our talents reach not, nor are our faculties, as I guess, able to advance. We are
$ 11. From whence it is obvious to confitted for
clude, that since our faculties are not moral know- fitted to penetrate into the internal fabric ledge and
and real essences of bodies ; but yet natural ima
plainly discover to us the being of a God, provements.
and the knowledge of ourselves, enough to lead us into a full and clear discovery of our duty and great concernment; it will become us, as rational creatures, to employ those faculties we have about what they are most adapted to, and follow the direction of nature, where it seems to point us out the
way. For it is rational to conclude that our proper employment lies in those inquiries, and in that sort of knowledge, which is most suited to our natural capacities, and carries in it our greatest interest, i.e. the condition of our eternal estate. Hence I think I may conclude, that morality is the proper science and business of mankind in general ; (who are both concerned and fitted to search out their summum bonum) as several arts, conversant about several parts of nature, are the lot and private talent of particular men, for the common use of human life, and their own particular subsistence in this world. Of what consequence the discovery of one natural body, and its properties, may be to human life, the whole great continent of America is a convincing instance; whose ignorance in useful arts, and want of the greatest part of the conveniencies of life, in a country that abounded with all sorts of natural plenty, I think, may be attributed to their ignorance of what was to be found in a very ordinary despicable stone, I mean the mineral of iron. And whatever we think of our parts or improvements in this part of the world, where knowledge and plenty seem to vie with each other; yet to any one, that will seriously reflect on it, I suppose it will appear past doubt, that were the use of iron lost among us, we should in a few ages be unavoidably reduced to the wants and ignorance of the ancient savage Americans, whose natural endowments and provisions come no way short of those of the most flourishing and polite nations. So that he who first made known the use of that contemptible mineral may be truly styled the father of arts, and author of plenty.
$ 12. I would not therefore be thought But must to disesteem or dissuade the study of nature. I readily agree the contemplation hypotheses of his works gives us occasion to admire, revere, and glorify their Author : and, if principles. rightly directed, may be of greater benefit to man
kind than the monuments of exemplary charity, that have at so great charge been raised by the founders of hospitals and alms-houses. He that first invented printing, discovered the use of the compass, or made public the virtue and right use of kin kina, did more for the propagation of knowledge, for the supply and increase of useful commodities, and saved more from the grave, than those who built colleges, work-houses, and hospitals. All that I would say is, that we should not be too forwardly possessed with the opinion or expectation of knowledge, where it is not to be had, or by ways that will not attain to it; that we should not take doubtful systems for complete sciences, nor unintelligible notions for scientifical demonstrations. In the knowledge of bodies, we must be content to glean what we can from particular experiments; since we cannot, from a discovery of their real essences, grasp at a time whole sheaves, and in bundles comprehend the nature and properties of whole species together. Where our inquiry is concerning co-existence, or repugnancy to co-exist, which by contemplation of our ideas we cannot discover; there experience, observation, and natural history must give us by our senses, and by retail, an insight into corporeal substances. The knowledge of bodies we must get by our senses, warily employed in taking notice of their qualities and operations on one another; and what we hope to know of separate spirits in this world we must, I think, expect only from revelation. He that shall consider how little general maxims, precarious principles, and hypotheses laid down at pleasure, have promoted true knowledge, or helped to satisfy the inquiries of rational men after real improvementshow little, I say, the setting out at that end has, for many ages together, advanced men's progress towards the knowledge of natural philosophy, will think we have reason to thank those, who in this latter age have taken another course, and have trod out to us, though not an easier way to
learned ignorance, yet a surer way to profitable knowledge.
$ 13. Not that we may not, to explain The true any phænomena of nature, make use of use of hya any probable hypothesis whatsoever : hy- potheses. potheses, if they are well made, are at least great helps to the memory, and often direct us to new discoveries. But my meaning is, that we should not take up any one too hastily (which the mind, that would always penetrate into the causes of things, and have principles to rest on, is very apt to do) till we have very well examined particulars, and made several experiments in that thing which we would explain by our hypothesis, and see whether it will agree to them all, whether our principles will carry us quite through, and not be as inconsistent with one phænomenon of nature as they seem to accommodate and explain another. And at least that we take care, that the name of principles deceive us not, nor impose on üs, by making us receive that for an unquestionable truth which is really at best but a very doubtful conjecture, such as are most (I had almost said all) of the hypotheses in natural philosophy.
$ 14. But whether natural philosophy Clear and be capable of certainty or no, the ways to distinct enlarge our knowledge, as far as we are ideas with capable, seem to me, in short, to be these settled two:
the finding First, the first is to get and settle in our
of those minds determined ideas of those things, which show whereof we have general or specific their agreenames; at least, so many of them as we would consider and improve our know
ways ledge in, or reason about. And if they
And if they to enlarge be specific ideas of substances, we should
our knowendeavour also to make them as complete
ledge. as we can, whereby I mean that we should put together as many simple ideas as, being constantly observed to co-exist, may perfectly determine the species:
ment or dis
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