them to do so, is the wonted veracity of the speaker in other cases, or his supposed veracity in this.

§. 2. Our knowledge, as has been shown, It is to supbeing very narrow, and we not happy ply the want enough to find certain truth in every thing of knowwhich we have occasion to consider; most ledge. of the propositions we think, reason, discourse, nay act upon, are such, as we cannot have undoubted knowledge of their truth; yet some of them border so near upon certainty, that we make no doubt at all about them; but assent to them as firmly, and act, according to that assent, as resolutely, as if they were infallibly demonstrated, and that our knowledge of them was perfect and certain. But there being degrees herein from the very neighbourhood of certainty and demonstration, quite down to improbability and unlikeness, even to the confines of impossibility; and also degrees of assent from full assurance and confidence, quite down to conjecture, doubt, and distrust: I shall come now, (having, as I think, found out the bounds of human knowledge and certainty) in the next place, to consider the several degrees and grounds of probability, and assent or faith. §. 3. Probability is likeliness to be true, the very notation of the word signifying which makes Being that such a proposition, for which there be us presume arguments or proofs, to make it pass or be things to be received for true. The entertainment the true before mind gives this sort of propositions, is called them to be so. belief, assent, or opinion, which is the

admitting or receiving any proposition for true, upon arguments or proofs that are found to persuade us to receive it as true, without certain knowledge that it is so. And herein lies the difference between probability and certainty, faith and knowledge, that in all the parts of knowledge there is intuition; each immediate idea, each step has its visible and certain connexion; in belief, not so. That which makes me believe is something extraneous to the thing I believe; something not evidently joined on both sides to, and so not manifestly showing the agreement or disagreement of those ideas that are under consideration,

The grounds of probability are two; conformity with our own experience,

or the testimony of others expe

rience.

rience.

§. 4. Probability then, being to supply the defect of our knowledge, and to guide us where that fails, is always conversant about propositions, whereof we have no certainty, but only some inducements to receive them for true. The grounds of it are, in short, these two following.

First, the conformity of any thing with our own knowledge, observation, and expe

Secondly, the testimony of others, vouching their observation and experience. In the testimony of others, is to be considered, 1. The number. 2. The integrity. 3. The skill of the witnesses. 4. The design of the author, where it is a testimony out of a book cited. 5. The consistency of the parts, and circumstances of the relation. 6. Contrary testimonies.

In this all

the arguments pro and con ought to be examined before we come to a judg

5. Probability wanting that intuitive evidence, which infallibly determines the understanding, and produces certain knowledge, the mind, if it would proceed rationally, ought to examine all the grounds of probability, and see how they make more or less for or against any proposition, before it assents to, or dissents from it; and upon a due balancing the whole, reject, or receive it, with a more or less firm assent, proportionably to the preponderancy of the greater grounds of probability on one side or the other. For example:

ment.

If I myself see a man walk on the ice, it is past probability; it is knowledge; but if another tells me he saw a man in England, in the midst of a sharp winter, walk upon water hardened with cold; this has so great conformity with what is usually observed to happen, that I am disposed by the nature of the thing itself to assent to it, unless some manifest suspicion attend the relation of that matter of fact. But if the same thing be told to one born between the tropics, who never saw nor heard of any such thing before, there the whole probability relies on testimony: and as the relators are more in number, and of more credit, and have no interest to

speak contrary to the truth; so that matter of fact is like to find more or less belief. Though to a man whose experience has always been quite contrary, and who has never heard of any thing like it, the most untainted credit of a witness will scarce be able to find belief. As it happened to a Dutch ambassador, who entertaining the king of Siam with the particularities of Holland, which he was inquisitive after, amongst other things told him, that the water in his country would sometimes, in cold weather, be so hard, that men walked upon it, and that it would bear an elephant if he were there. To which the king replied, "Hitherto I have "believed the strange things you have told me, because “I look upon you as a sober fair man, but now I am ❝ sure you lye."

They being capable of great va

riety.

§. 6. Upon these grounds depends the probability of any proposition: and as the conformity of our knowledge, as the certainty of observations, as the frequency and constancy of experience, and the number and credibility of testimonies, do more or less agree or disagree with it, so is any proposition in itself more or less probable. There is another, I confess, which though by itself it be no true ground of probability, yet is often made use of for one, by which men most commonly regulate their assent, and upon which they pin their faith more than any thing else, and that is the opinion of others: though there cannot be a more dangerous thing to rely on, nor more likely to mislead one; since there is much more falsehood and errour among men, than truth and knowledge. And if the opinions and persuasions of others, whom we know and think well of, be a ground of assent, men have reason to be Heathens in Japan, Mahometans in Turky, Papists in Spain, Protestants in England, and Lutherans in Sweden. But of this wrong ground of assent I shall have occasion to speak more at large in another place.

Our assent ought to be

regulated by the grounds ofprobability.

CHAP. XVI.

Of the Degrees of Assent.

§. 1. THE grounds of probability we have laid down in the foregoing chapter; as they are the foundations on which our assent is built, so are they also the measure whereby its several degrees are, or ought to be regulated: only we are to take notice, that whatever grounds of probability there may be, they yet operate no farther on the mind, which searches after truth, and endeavours to judge right, than they appear; at least in the first judgment or search that the mind makes. I confess, in the opinions men have, and firmly stick to, in the world, their assent is not always from an actual view of the reasons that at first prevailed with them: it being in many cases almost impossible, and in most very hard, even for those who have. very admirable memories, to retain all the proofs, which upon a due examination made them embrace that side. of the question. It suffices that they have once with care and fairness sifted the matter as far as they could ; and that they have searched into all the particulars, that they could imagine to give any light to the question: and with the best of their skill cast up the account upon the whole evidence: and thus having once found on which side the probability appeared to them, after as full and exact an enquiry as they can make, they lay up the conclusion in their memories, as a truth they have discovered; and for the future they remain satisfied with the testimony of their memories, that this is the opinion, that by the proofs they have once seen of it deserves such a degree of their assent as they afford it.

These cannot always be actually in view, and

then we must

§. 2. This is all that the greatest part of men are capable of doing, in regulating their opinions and judgments; unless a man will exact of them, either to retain distinctly in their memories all the proofs concerning

content ourselves with brance that

the remem

we once saw

ground for such a degree of assent.

any probable truth, and that too in the same order, and regular deduction of consequences in which they have formerly placed or seen them; which sometimes is enough to fill a large volume on one single question or else they must require a man, for every opinion that he embraces, every day to examine the proofs: both which are impossible. It is unavoidable therefore that the memory be relied on in the case, and that men be persuaded of several opinions, whereof the proofs are not actually in their thoughts; nay, which perhaps they are not able actually to recal. Without this the greatest part of men must be either very sceptics, or change every moment, and yield themselves up to whoever, having lately studied the question, offers them arguments; which, for want of memory, they are not able presently to answer. §. 3. I cannot but own, that men's sticking to their past judgment, and adhering firmly to conclusions formerly made, is often the cause of great obstinacy in errour and mistake. But the fault is not that

they

The ill consequence of

this, if our former judg

ments were

made.

rely on their memories for what they have not rightly before well judged; but because they judged before they had well examined. May we not find a great number (not to say the greatest part) of men that think they have formed right judgments of several matters; and that for no other reason, but because they never thought otherwise? who imagine themselves to have judged right, only because they never questioned, never examined their own opinions? Which is indeed to think they judged right, because they never judged at all: and yet these of all men hold their opinions with the greatest stiffness; those being generally the most fierce and firm in their tenets, who have least examined them. What we once know, we are certain is so; and we may be secure, that there are no latent proofs undiscovered, which may overturn our knowledge, or bring it in doubt. But, in matters of probability, it is not in every case we can be sure that we have all the particulars before us, that any way concern the question; and that