And if there should be any new and uncontroulable evidence brought against these old or beloved sentiments, do not wink your eyes fast against the light, but part with any thing for the sake of truth: remember when you overcome an error you gain truth; the victory is on your side, and the advantages are all your own.

I confess those grand principles of belief and prac tice which universally influence our conduct both with regard to this life and the life to come, should be supposed to be well settled in the first years of our studies, such as, the existence and providence of God, the truth of Christianity, the authority of scripture, the general rules of morality, &c. We should avoid a light Auttering genius, ever ready to change our foundations, and to be carried about with every kind of doctrine. To guard against which inconveniences, we should labour with earnest diligence and fervent prayer, that our most fundamental and important points of belief and practice may be established upon just grounds of reason and scripture when we come to years of discretion, and fit to judge for ourselves in such important points. Yet since it is possible that the folly or prejudices of younger years may have established persons in some mistaken sentiments, even in very important matters, we should always hold ourselves ready to receive any new advantage toward the direction or improvement even of our established principles, as well as opini ons of lesser moment.

CHAP. V.

SPECIAL RULES TO DIRECT US IN JUDGING OF PARTICULAR OBJECTS.

IT would be endless to run through all those particular objects concerning which we have occasion to pass a judgment at one time or another. Things of the most frequent occurrence, of the widest extent, and of the greatest importance, are the objects and exercises of sense, of reason, and speculation: the matters of morality, religion, and prudence, of human and divine testimony, together with the es

says of reasoning upon things past and future. Special rules relating to all these will be the subject of the following sections.

SECT. I.-Principles and Rules of Judgment concerning the Objects of Sense.

Though our senses are sometimes liable to be deceived, yet when they are rightly disposed, and fitly exercised about their proper objects, with the just assistance of reason, they give us sufficient evidence of truth.

This may be proved from an argument drawn from the wisdom, goodness, and faithfulness of God our creator. It was he gave us our senses, and he would not make us of such a constitution as to be liable to perpetual deception and unavoidable error in using these faculties of sense in the best manner we are capable of, about these very things which are the proper objects of them.

This may be proved also by the ill consequences that would follow from the supposition of the contrary. If we could have no certainty of the dictates of our senses, we could never be sure of any of the common affairs and occurrences of life. Men could not transact any of their civil or moral concerns with any certainty or justice: nor indeed could we eat or drink, walk or move with safety. Our senses direct us in all these.

Again, the matters of religion depend in some measure upon the certainty of the dictates of sense; for faith comes by hearing; and it is to our senses that God appeals in working miracles to prove his own revelation. Now, if when our eyes and ears, and other organs of sense are rightly disposed and exercised about their proper objects, they were always liable to be deceived, there could be no knowledge of the gospel, no proof of divine revelation by visions, voices, or miracles.

Our senses will discover things near us and round about us, which are necessary for our present state, with sufficient exactness, and things distant also, as far as they relate to our necessary use of them.

Nor is there need of any more accurate rules for

the use of our senses in the judgment of all the common affairs of life, or even of miraculous and divine operations, than the vulgar part of mankind are sufficiently acquainted with by nature, and by their own daily observations.

But if we would express these rules in a more exact manner, how to judge by the dictates of our senses, they should be represented thus:

:

1. We must take care that the organs of our sense be rightly disposed, and not under the power of any distemper or considerable decay: as, for instance, that our eyes are not tinctured with the jaundice, when we would judge of colours, lest we pronounce them all yellow that our hands are not burning in a fever, or benumbed with frost or the palsey, when we would judge of the heat or coldness of any object; that our palate be not vitiated by any disease, or by some other improper state, when we would judge of the true taste of any solid or liquid. This direction relates to all our senses, but the following rules chiefly refer to our sight.

2. We must observe whether the object be at a proper distance, for if it be too near, or too far off, our eyes will not sufficiently distinguish many things which are properly the objects of sight; and there. fore (if possible) we must make nearer approaches to the object, or remove farther from it, till we have obtained that due distance which gives us the clearest perception.

3. We must not employ our sight to take a full survey at once of objects that are too large for it, but we must view them by parts, and then judge of the whole: nor must our senses judge of objects too small; for some things which appear through glasses to be really and distinctly existent, are either utterly invisible, or greatly confused, when we would judge of them by the naked eye.

4. We must place ourselves in such a position toward the object, or place the object in such a position toward our eye, as may give us the clearest representation of it; for a different position greatly alters the appearance of the shape of bodies. And for this reason we should change the position both of

the eye and the object in some cases, that by viewing the object in several appearances, we may pass a more complete and certain judgment concerning it.

5. We must consider what the medium is by which objects are represented to our senses; whether it be thinner or thicker; whether it be air, or vapour, or water, or glass, &c. whether it be duly enlightened or dusky; whether it reflect or refract, or only transmit the appearance of the subject: and whether it be tinctured with any particular colour; whether it be moving or at rest.

6. We must sometimes use other helps to assist our senses; and if we make use of glasses, we must make all just allowances for the thickness or thinness of them, for the clearness or dulness, for the smoothness or roughness, for the plainness, the convexity or concavity of them, and for the distance at which these glasses are placed from the eye, or from the object, (or from one another, if there be two or more glasses used) and all this according to the rules of art. The same sort of caution should be used also in mediums which assist the hearing, such as speaking-trumpets, hearing-trumpets, &c.

7. If the object may be proposed to more senses than one, let us call in the assistance of some other senses to examine it, and this will encrease the evidence of what one sense dictates. Ex. gr. Our ear may assist our eye in judging of the distance of bo. dies, which are both visible and sonorous, as an exploded cannon, or a cloud charged with thunder. Our feeling may assist our sight iu judging of the kind, shape, situation, or distance of bodies that are nearer at hand, as whether a garment be silk or stuff, &c. So if I both see, hear, and embrace my friend, I am sure he is present.

8. We should also make several trials, at some distant times, and in different circumstances, comparing former experiments with later, and our own observations with those of other persons.

It is by such methods as these that modern philo sophy has been so greatly improved by the use of sensible experiments.

SECT. II.-Principles and Rules of Judgment in Matters of Reason and Speculation.

It is by reason we judge both in matters of speculation and practice: there are peculiar rules which relate to things practical, whether they be matters of religion, morality, or prudence; yet many things in this section may be applied to practical enquiries and matters of faith, though it chiefly relates to knowledge or speculations of reason.

1. Whatsoever clear ideas we can join together without inconsistency, are to be counted possible, because almighty power can make whatsoever we can conceive.

2. From the mere possibility of a thing we cannot infer its actual existence; nor from the non-existence of it can we infer its impossibility.

Note, the idea of God seems to claim an exemption from this general rule; for if he be possible, he certainly exists, because the very idea includes eternity, aud he cannot begin to be: if he exist not, he is impossible, for the very same reason.

3. Whatsoever is evidently contained in the idea of any thing, may be affirmed of that thing, with certainty. Reason is contained in the idea of a man; and existence is contained in the idea of God; and therefore we may affirm God exists, and man is reasonable.

4. It is impossible that the same thing should be, and not be, at the same time, and in the same re spect. Thence it follows, that two contradictory ideas cannot be joined in the same part of the same subject, at the same time, and in the same respects; or, that two contradictory propositions can never be both true.

5. The more we converse with any subject in its various properties, the better knowledge of it we are likely to attain; and by frequent and repeated inquiries and experiments, reasonings and conversations about it, we confirm our true judgments of that thing, and correct our former mistakes.

6. Yet after our utmost inquiries, we can never be assured by reason that we know all the powers and properties of any finite being.