1. Our assent ought to be regulated by the grounds of probability. 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 further 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 al 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 inquiry 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.
2. These cannot always be actually in view; and then we must content ourselves with the
remembrance that we once saw ground for such a degree of assent. 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 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 recall. Without this, the greatest part of
men must be either very sceptic; 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. The ill consequence of this, if our former judgments were not rightly made. 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 error and mistake. But the fault is not that they rely on their memories for
what they have 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? that 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 there is no evidence behind, and yet unseen, which may cast the probability on
the other side, and outweigh al that at present seems to preponderate with us. Who almost is there
that hath the leisure, patience, and means to collect together all the proofs concerning most of the
opinions he has, so as safely to conclude that he hath a clear and full view; and that there is no
more to be alleged for his better information? And yet we are forced to determine ourselves on the
one side or other. The conduct of our lives, and the management of our great concerns, will not bear
delay: for those depend, for the most part, on the determination of our judgment in points wherein
we are not capable of certain and demonstrative knowledge, and wherein it is necessary for us to
embrace the one side or the other.
4. The right use of it, mutual charity and forbearance, in a necessary diversity of opinions. Since,
therefore, it is unavoidable to the greatest part of men, if not all, to have several opinions, without
certain and indubitable proofs of their truth; and it carries too great an imputation of ignorance,
lightness, or folly for men to quit and renounce their former tenets presently upon the offer of an
argument which they cannot immediately answer, and show the insufficiency of: it would, methinks,
become all men to maintain peace, and the common offices of humanity, and friendship, in the
diversity of opinions; since we cannot reasonably expect that any one should readily and
obsequiously quit his own opinion, and embrace ours, with a blind resignation to an authority which
the understanding of man acknowledges not. For however it may often mistake, it can own no other
guide but reason, nor blindly submit to the will and dictates of another. If he you would bring over to
your sentiments be one that examines before he assents, you must give him leave at his leisure to
go over the account again, and, recalling what is out of his mind, examine all the particulars, to see
on which side the advantage lies: and if he will not think our arguments of weight enough to engage
him anew in so much pains, it is but what we often do ourselves in the like case; and we should take
it amiss if others should prescribe to us what points we should study. And if he be one who takes his
opinions upon trust, how can we imagine that he should renounce those tenets which time and
custom have so settled in his mind, that he thinks them self-evident, and of an unquestionable
certainty; or which he takes to be impressions he has received from God himself, or from men sent
by him? How can we expect, I say, that opinions thus settled should be given up to the arguments or
authority of a stranger or adversary, especially if there be any suspicion of interest or design, as
there never fails to be, where men find themselves ill treated? We should do well to commiserate
our mutual ignorance, and endeavour to remove it in all the gentle and fair ways of information; and
not instantly treat others ill, as obstinate and perverse, because they will not renounce their own,
and receive our opinions, or at least those we would force upon them, when it is more than probable
that we are no less obstinate in not embracing some of theirs. For where is the man that has
incontestable evidence of the truth of all that he holds, or of the falsehood of all he condemns; or
can say that he has examined to the bottom all his own, or other men's opinions? The necessity of
believing without knowledge, nay often upon very slight grounds, in this fleeting state of action and
blindness we are in, should make us more busy and careful to inform ourselves than constrain
others. At least, those who have not thoroughly examined to the bottom all their own tenets, must
confess they are unfit to prescribe to others; and are unreasonable in imposing that as truth on other
men's belief, which they themselves have not searched into, nor weighed the arguments of
probability, on which they should receive or reject it. Those who have fairly and truly examined, and
are thereby got past doubt in all the doctrines they profess and govern themselves by, would have a
juster pretence to require others to follow them: but these are so few in number, and find so little
reason to be magisterial in their opinions, that nothing insolent and imperious is to be expected from
them: and there is reason to think, that, if men were better instructed themselves, they would be less
imposing on others.
5. Probability is either of sensible matter of fact, capable of human testimony, or of what is beyond
the evidence of our senses. But to return to the grounds of assent, and the several degrees of it, we
are to take notice, that the propositions we receive upon inducements of probability are of two sorts:
either concerning some particular existence, or, as it is usually termed, matter of fact, which, falling
under observation, is capable of human testimony; or else concerning things, which, being beyond
the discovery of our senses, are not capable of any such testimony.
6. The concurrent experience of all other men with ours, produces assurance approaching to
knowledge. Concerning the first of these, viz., Particular matter of fact.
I. Where any particular thing, consonant to the constant observation of ourselves and others in the
like case, comes attested by the concurrent reports of all that mention it, we receive it as easily, and
build as firmly upon it, as if it were certain knowledge; and we reason and act thereupon with as little
doubt as if it were perfect demonstration. Thus, if all Englishmen, who have occasion to mention it,
should affirm that it froze in England the last winter, or that there were swallows seen there in the
summer, I think a man could almost as little doubt of it as that seven and four are eleven. The first,
therefore, and highest degree of probability, is, when the general consent of all men, in all ages, as
far as it can be known, concurs with a man's constant and never-failing experience in like cases, to
confirm the truth of any particular matter of fact attested by fair witnesses: such are all the stated
constitutions and properties of bodies, and the regular proceedings of causes and effects in the
ordinary course of nature. This we call an argument from the nature of things themselves. For what
our own and other men's constant observation has found always to be after the same manner, that
we with reason conclude to be the effect of steady and regular causes; though they come not within
the reach of our knowledge. Thus, That fire warmed a man, made lead fluid, and changes the colour
or consistency in wood or charcoal; that iron sunk in water, and swam in quicksilver: these and the
like propositions about particular facts, being agreeable to our constant experience, as often as we
have to do with these matters; and being generally spoke of (when mentioned by others) as things
found constantly to be so, and therefore not so much as controverted by anybody--we are put past
doubt that a relation affirming any such thing to have been, or any prediction that it will happen
again in the same manner, is very true. These probabilities rise so near to certainty, that they govern
our thoughts as absolutely, and influence all our actions as fully, as the most evident demonstration;
and in what concerns us we make little or no difference between them and certain knowledge. Our
belief, thus grounded, rises to assurance.
7. II. Unquestionable testimony, and our own experience that a thing is for the most part so, produce
confidence. The next degree of probability is, when I find by my own experience, and the agreement
of all others that mention it, a thing to be for the most part so, and that the particular instance of it is
attested by many and undoubted witnesses: v.g. history giving us such an account of men in all
ages, and my own experience, as far as I had an opportunity to observe, confirming it, that most
men prefer their private advantage to the public: if all historians that write of Tiberius, say that
Tiberius did so, it is extremely probable. And in this case, our assent has a sufficient foundation to
raise itself to a degree which we may call confidence.
8. III. Fair testimony, and the nature of the thing indifferent, produce unavoidable assent. In things
that happen indifferently, as that a bird should fly this or that way; that it should thunder on a man's
right or left hand, etc., when any particular matter of fact is vouched by the concurrent testimony of
unsuspected witnesses, there our assent is also unavoidable. Thus: that there is such a city in Italy
as Rome: that about one thousand seven hundred years ago, there lived in it a man, called Julius
Caesar; that he was a general, and that he won a battle against another, called Pompey. This,
though in the nature of the thing there be nothing for nor against it, yet being related by historians of
credit, and contradicted by no one writer, a man cannot avoid believing it, and can as little doubt of it
as he does of the being and actions of his own acquaintance, whereof he himself is a witness.
9. Experience and testimonies clashing infinitely vary the degrees of probability. Thus far the matter
goes easy enough. Probability upon such grounds carries so much evidence with it, that it naturally
determines the judgment, and leaves us as little liberty to believe or disbelieve, as a demonstration
does, whether we will know, or be ignorant. The difficulty is, when testimonies contradict common
experience, and the reports of history and witnesses clash with the ordinary course of nature, or with
one another; there it is, where diligence, attention, and exactness are required, to form a right
judgment, and to proportion the assent to the different evidence and probability of the thing: which
rises and falls, according as those two foundations of credibility, viz., common observation in like
cases, and particular testimonies in that particular instance, favour or contradict it. These are liable
to so great variety of contrary observations, circumstances, reports, different qualifications, tempers,
designs, oversights, etc., of the reporters, that it is impossible to reduce to precise rules the various
degrees wherein men give their assent. This only may be said in general, That as the arguments
and proofs pro and con, upon due examination, nicely weighing every particular circumstance, shall
to any one appear, upon the whole matter, in a greater or less degree to preponderate on either
side; so they are fitted to produce in the mind such different entertainments, as we call belief,
conjecture, guess, doubt, wavering, distrust, disbelief, etc.
10. Traditional testimonies, the further removed the less their proof becomes. This is what concerns
assent in matters wherein testimony is made use of: concerning which, I think, it may not be amiss
to take notice of a rule observed in the law of England; which is, That though the attested copy of a
record be good proof, yet the copy of a copy, ever so well attested, and by ever so credible
witnesses, will not be admitted as a proof in judicature. This is so generally approved as reasonable,
and suited to the wisdom and caution to be used in our inquiry after material truths, that I never yet
heard of any one that blamed it. This practice, if it be allowable in the decisions of right and wrong,
carries this observation along with it, viz., That any testimony, the further off it is from the original
truth, the less force and proof it has. The being and existence of the thing itself, is what I call the
original truth. A credible man vouching his knowledge of it is a good proof; but if another equally
credible do witness it from his report, the testimony is weaker: and a third that attests the hearsay of
an hearsay is yet less considerable. So that in traditional truths, each remove weakens the force of
the proof: and the more hands the tradition has successively passed through, the less strength and
evidence does it receive from them. This I thought necessary to be taken notice of: because I find
amongst some men the quite contrary commonly practised, who look on opinions to gain force by
growing older; and what a thousand years since would not, to a rational man contemporary with the
first voucher, have appeared at all probable, is now urged as certain beyond all question, only
because several have since, from him, said it one after another. Upon this ground propositions,
evidently false or doubtful enough in their first beginning, come, by an inverted rule of probability, to
pass for authentic truths; and those which found or deserved little credit from the mouths of their first
authors, are thought to grow venerable by age, are urged as undeniable.
11. Yet history is of great use. I would not be thought here to lessen the credit and use of history: it
is all the light we have in many cases, and we have in many cases, and we receive from it a great
part of the useful truths we have, with a convincing evidence. I think nothing more valuable than the
records of antiquity: I wish we had more of them, and more uncorrupted. But this truth itself forces
me to say, That no probability can rise higher than its first original. What has no other evidence than
the single testimony of one only witness must stand or fall by his only testimony, whether good, bad,
or indifferent; and though cited afterwards by hundreds of others, one after another, is so far from
receiving any strength thereby, that it is only the weaker. Passion, interest, inadvertency, mistake of
his meaning, and a thousand odd reasons, or capricios, men's minds are acted by, (impossible to be
discovered,) may make one man quote another man's words or meaning wrong. He that has but
ever so little examined the citations of writers, cannot doubt how little credit the quotations deserve,
where the originals are wanting; and consequently how much less quotations of quotations can be
relied on. This is certain, that what in one age was affirmed upon slight grounds, can never after
come to be more valid in future ages by being often repeated. But the further still it is from the
original, the less valid it is, and has always less force in the mouth or writing of him that last made
use of it than in his from whom he received it.
12. In things which sense cannot discover, analogy is the great rule of probability. [Secondly], The
probabilities we have hitherto mentioned are only such as concern matter of fact, and such things as
are capable of observation and testimony. There remains that other sort, concerning which men
entertain opinions with variety of assent, though the things be such, that falling not under the reach
of our senses, they are not capable of testimony. Such are, 1. The existence, nature and operations
of finite immaterial beings without us; as spirits, angels, devils, etc. Or the existence of material
beings which, either for their smallness in themselves or remoteness from us, our senses cannot
take notice of--as, whether there be any plants, animals, and intelligent inhabitants in the planets,
and other mansions of the vast universe. 2. Concerning the manner of operation in most parts of the
works of nature: wherein, though we see the sensible effects, yet their causes are unknown, and we
perceive not the ways and manner how they are produced. We see animals are generated,
nourished, and move; the loadstone draws iron; and the parts of a candle, successively melting, turn
into flame, and give us both light and heat. These and the like effects we see and know: but the
causes that operate, and the manner they are produced in, we can only guess and probably
conjecture. For these and the like, coming not within the scrutiny of human senses, cannot be
examined by them, or be attested by anybody; and therefore can appear more or less probable, only
as they more or less agree to truths that are established in our minds, and as they hold proportion to
other parts of our knowledge and observation. Analogy in these matters is the only help we have,
and it is from that alone we draw all our grounds of probability. Thus, observing that the bare
rubbing of two bodies violently one upon another, produces heat, and very often fire itself, we have
reason to think, that what we call heat and fire consists in a violent agitation of the imperceptible
minute parts of the burning matter. Observing likewise that the different refractions of pellucid
bodies produce in our eyes the different appearances of several colours; and also, that the different
ranging and laying the superficial parts of several bodies, as of velvet, watered silk, etc., does the
like, we think it probable that the colour and shining of bodies is in them nothing but the different
arrangement and refraction of their minute and insensible parts. Thus, finding in all parts of the
creation, that fall under human observation, that there is a gradual connexion of one with another,
without any great or discernible gaps between, in all that great variety of things we see in the world,
which are so closely linked together, that, in the several ranks of beings, it is not easy to discover
the bounds betwixt them; we have reason to be persuaded that, by such gentle steps, things ascend
upwards in degrees of perfection. It is a hard matter to say where sensible and rational begin, and
where insensible and irrational end: and who is there quick-sighted enough to determine precisely
which is the lowest species of living things, and which the first of those which have no life? Things,
as far as we can observe, lessen and augment, as the quantity does in a regular cone; where,
though there be a manifest odds betwixt the bigness of the diameter at a remote distance, yet the
difference between the upper and under, where they touch one another, is hardly discernible. The
difference is exceeding great between some men and some animals: but if we will compare the
understanding and abilities of some men and some brutes, we shall find so little difference, that it
will be hard to say, that that of the man is either clearer or larger. Observing, I say, such gradual and
gentle descents downwards in those parts of the creation that are beneath man, the rule of analogy
may make it probable, that it is so also in things above us and our observation; and that there are
several ranks of intelligent beings, excelling us in several degrees of perfection, ascending upwards
towards the infinite perfection of the Creator, by gentle steps and differences, that are every one at
no great distance from the next to it. This sort of probability, which is the best conduct of rational
experiments, and the rise of hypothesis, has also its use and influence; and a wary reasoning from
analogy leads us often into the discovery of truths and useful productions, which would otherwise lie
concealed.
13. One case where contrary experience lessens not the testimony. Though the common
experience and the ordinary course of things have justly a mighty influence on the minds of men, to
make them give or refuse credit to anything proposed to their belief; yet there is one case, wherein
the strangeness of the fact lessens not the assent to a fair testimony given of it. For where such
supernatural events are suitable to ends aimed at by Him who has the power to change the course
of nature, there, under such circumstances, that may be the fitter to procure belief, by how much the
more they are beyond or contrary to ordinary observation. This is the proper case of miracles, which,
well attested, do not only find credit themselves, but give it also to other truths, which need such
confirmation.
14. The bare testimony of divine revelation is the highest certainty. Besides those we have hitherto
mentioned, there is one sort of propositions that challenge the highest degree of our assent, upon
bare testimony, whether the thing proposed agree or disagree with common experience, and the
ordinary course of things, or no. The reason whereof is, because the testimony is of such an one as
cannot deceive nor be deceived: and that is of God himself. This carries with it an assurance
beyond doubt, evidence beyond exception. This is called by a peculiar name, revelation, and our
assent to it, faith, which as absolutely determines our minds, and as perfectly excludes all wavering,
as our knowledge itself; and we may as well doubt of our own being, as we can whether any
revelation from God be true. So that faith is a settled and sure principle of assent and assurance,
and leaves no manner of room for doubt or hesitation. Only we must be sure that it be a divine
revelation, and that we understand it right: else we shall expose ourselves to all the extravagancy of
enthusiasm, and all the error of wrong principles, if we have faith and assurance in what is not divine
revelation. And therefore, in those cases, our assent can be rationally no higher than the evidence
of its being a revelation, and that this is the meaning of the expressions it is delivered in. If the
evidence of its being a revelation, or that this is its true sense, be only on probable proofs, our
assent can reach no higher than an assurance or diffidence, arising from the more or less apparent
probability of the proofs. But of faith, and the precedency it ought to have before other arguments of
persuasion, I shall speak more hereafter; where I treat of it as it is ordinarily placed, in
contradistinction to reason; though in truth it be nothing else but an assent founded