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tending to prove positions which cannot be both true, the mind must decide on the comparative strength of the opposite evidences, before it yield to either.
But is this the case in the supposition first made ? By no means. The two thousand instances formerly known, and the single instance attested, as they relate to different facts, though of a contrary nature, are not contradictory. There is no inconsistency in believing both. There is no inconsistency in receiving the last on weaker evidence, (if it be sufficient evidence) not only than all the former together, but even than any of them singlv. Will it be said, that though the former instances are not themselves contradictory to the fact recently attested, they lead to a conclusion that is contradictory? I answer, It is true, that the experienced frequency of the conjunction of any two events, leads the mind to infer a similar conjunction in time to come. But let it at the same time be remarked, that no man considers this inference, as having equal evidence with any one of those past events, on which it is founded, and for the belief of which we have had sufficient testimony. Before then the method recommended by this author can turn to any account, it will be necessary for him to compute and determine with precision, how many hundreds, how many thousands, I might say how many myriads of instances, will confer such evidence on the conclusion founded on them, as will prove an equipoise for the testimony of one ocular witness, a man of probity, in a case of which he is allowed to be a competent judge.
There is in arithmetick a rule called REDUCTION, by which numbers of different denominations are brought to the same denomination. If this ingenious author shall invent a rule in logick, analogous to this, for reducing different classes of evidence to the same class, he will bless the world with a most important discovery. Then indeed he will have the honour to establish an everlasting peace in the republick of letters ; then we shall have the happiness to see controversy of every kind, theological, historical, philosophical, receive its mortal wound : for though, in every question, we could not even then determine with certainty, on which side the trutn lay, we could always determine (and that is the utmost the nature of the thing admits) with as much accuracy as geometry and algebra can afford, on which side the probability lav, and in what degree. But till this metaphysical reduction is discovered, it will be impossible where the evidences are of different orders, to ascertain by subtraction the superiour evidence. We could not but esteem him a novice in arithmetick, who being asked, whether seven pounds or eleven pence make the greater sum, and what is the difference? should, by attende ing solely to the numbers, and overlooking the value, conclude that eleven pence were the greater, and that it exceeded the other by four. Must we not be equal novices in reasoning, if we follow the same absurd method ? Must we not fall into as great blunders ? Of as little significancy do we find the balance. Is the value of things heterogeneal to be detera mined merely by weight ? Shall silver be weighed against lead, or copper against iron ? If in exchange for a piece of gold, I were offered some counters of baser metal, is it not obvious, that till I know the comparative value of the metals, in vain shall I attempt to find what is equivalent, by the assistance either of scales or arithmetick?
It is an excellent observation, and much to the purpose, which the late learned and pious bishop of Durham, in his admirable performance on the analogy of religion to the course of nature, hath made on this subject. “ There is a very strong presumption,” says he, “ against the most
ordinary facts, before the proof of them, which yet is over"come by almost any proof. There is a presumption of $ millions to one against the story of Cæsar, or of any other & man. For suppose a number of common facts, so and so « circumstanced, of which one had no kind of proof, should “happen to come into one's thoughts every one would, with« out any possible doubt, conclude them to be false. The « like may be said of a single common fact*.? What then, I may subjoin, shall be said of an uncommon fact ? And that an uncommon fact may be proved by testimony, hath not yet been made a question. But in order to illustrate the obser. vation above cited, suppose, first, one at random mentions, that at such an hour, of such a day, in such a part of the heavens, a comet will appear; the conclusion from experience would not be as millions, but as infinite to one, that the proposition is false. Instead of this, suppose you have the testimony of but one ocular witness, a man of integrity, and skilled in astronomy, that at such an hour, of such a day, in such a part of the heavens, a comet did appear; you will not hesitate one moment to give him credit. Yet all the presumption that was against the truth of the first supposition, though almost as strong evidence as experience can afford, was also against the truth of the second, before it was thus attested.
It is necessary to urge further, in support of this doctrine, that as the water in the canal cannot be made to rise higher than the fountain whence it flows ; so it is impossible, that the evidence of testimony, if it proceeded from experience,
• Part 2. chap. 2. $ 3.
should ever exceed that of experience, which is its sources Yet that it greatly exceeds this evidence, appears not only from what hath been observed already, but still more, from what I shall have occasion to observe in the sequel. One may safely affirm, that no conceivable conclusion from experience, can possess stronger evidence, than that which ascertains us of the regular succession and duration of day and night. The reason is, the instances on which this experience is founded, are both without number and without exception. Yet even this conclusion, the author admits, as we shall see in the third section, may, in a particular instance, not only be surmounted, but even annihilated by testimony.
Lastly, let it be observed, that the immediate conclusion: from experience is always general, and runs thus : « This is • the ordinary course of nature. Such an event may rea
sonably be expected, where all the circumstances are entirely similar.' But when we descend to particulars, the conclusion becomes weaker, being more indirect. For though all the known circumstances be similar, all the actual circumstances may not be similar : nor is it possible in any case to be assured (our knowledge of things being at best but superficial, that all the actual circumstances are known to us. On the contrary, the direct conclusion from testimony is always particular, and runs thus; This is the fact in such an indi. ?vidual instance. The remark now made will serve both to throw light on some of the preceding observations and to indicate the proper sphere of each species of evidence. Exe" perience of the past is the only rule whereby we can judge concerning the future: And as when the sun is below the horizon, we must do the best we can by light of the moon, or even of the stars ; so in all cases where we have no testimony, we are under a necessity of recurring to experience, and of balancing or numbering contrary observations* But
* Wherever such balancing or numbering can take place, the opposite evi.. dences must be entirely similar. It will rarely assist us in judging of facts supported by testimony ; for even where contradictory testimonies come to be considered, you will hardly find that the characters of the witnesses on the opposite sides are so precisely equal, as that an arithmetical operation will evolve the credibility. In matters of pure experience it hath often place. Hence the computations that have been made of the value of annuities, insurances, and several other commercial articles. In calculations concerning chances, the degree of probability may be determined with mathematical exactness. I shall here take the liberty, though the matter be not essential to the design of this tract, to correct an oversight in the essayist, who always supposes, that where contrary evidences must be balanced, the probability lies in the remainder or surplus, when the less number is subtracted from the greater. The probability doth not consist in the surplus, but in the ratio, or geometricai proportion, which the numbers on the opposite sides bear to each other. I explain myself thus. In favour of one sup.
the evidence resulting hence, even in the clearest cases, is acknowledged to be so weak, compared with that which results from testimony, that the strongest conviction built merely on the former, may be overturned by the slightest proof exhibited by the latter. Accordingly the future hath in all ages and nations been denominated the province of conjecture and uncertainty.
From what hath been said, the attentive reader will easily discover, that the author's argument against miracles, hath not the least affinity to the argument used by Dr. Tillotson against transubstantiation, with which Mr. Hume hath introduced his subject. Let us hear the argument, as it is related in the Essay, from the writings of the Archbishop. “ It is « acknowledged on all hands, says that learned prelate, that “ the authority either of the scripture or of tradition, is “ founded merely on the testimony of the apostles, who were « eye-witnesses to those miracles of our Saviour, by which he « proved his divine mission. Our evidence then for the truth « of the Christian religion, is less than the evidence for the " truth of our senses ; because even in the first authors of our « religion, it was no greater ; and it is evident, it must dimi. 66 nish in passing from them to their disciples ; nor can any « one be so certain of the truth of their testimony, as of the “ immediate objects of his senses. But a weaker evidence6 can never destroy a stronger; and therefore, were the doc“ trine of the real presence ever so clearly revealed in scripu ture, it were directly contrary to the rules of just reasoning « to give our assent to it. It contradicts sense, though both " the scripture and tradition, on which it is supposed to be “ built, carry not such evidence with them as sense, when they « are considered merely as external evidences, and are not “ brought home to every one's breast, by the immediate ope“ ration of the Holy Spirit*.” That the evidence of testimony is less than the evidence of sense, is undeniable. Sense is the source of that evidence, which is first transferred to the memory of the individual, as to a general reservoir, and thence transmitted to others by the channel of testimony. That the original evidence can never gain any thing, but must lose, by the transmission, is beyond dispute. What hath been rightly
posed event, there are 100 similar instances, against it 50. Iu another case under consideration, the favourable instances are 60, and only 10 unfavourable. Though the difference, or arithmetical proportion, which is 50, be the same in both cases, the probability is by no means equal, as the author's way of reasoning implies. The probability of the first event is as 100 10 50, or 2 to 1. The probability of the second is as 60 to 10, or 6 to 1. Cor.sequently on comparing the different examples, though both be probable, the second is thrice as probable as the first.
* p. 173, 174.
perceived, may be misremembered; what is rightly remem. bered may, through incapacity, or through ill intention, be misreported; and what is rightly reported may be misundere stood. In any of these four ways therefore, either by defect of memory, of elocution, or of veracity in the relater, or by misapprehension in the hearer, there is a chance, that the truth received by the information of the senses, may be misrepre sented or mistaken; now every such chance occasions a real diminution of the evidence. That the sacramental elements. are bread and wine, not flesh and blood, our sight and touch, and taste, and smell concur in testifying. If these senses are not to be credited, the apostles themselves could not have evi. dence of the mission of their master. For the greatest ex. ternal evidence they had, or could have, of his mission, was that which their senses gave them, of the reality of his miracles. But whatever strength there is in this argument with regard to the apostles, the argument with regard to us, who, for those miracles, have only the evidence, not of our own senses, but of their testimony, is incomparably stronger. In their case, it is sense contradicting sense ; in ours it is sense contradicting testimony. But what relation has this to the author's argument? None at all. Testimony, it is acknow ledged, is a weaker evidence than sense. But it hath been already evinced, that its evidence for particular facts is infinite ly stronger than that which the general conclusion from expes rience can afford us.Testimony holds directly of memory and sense. Whatever is duly attested must be remembered by the witness; whatever is duly remembered must once have been perceived. But nothing similar takes place with regard to experience, nor can testimony, with any appearance of meaning, be said to hold of it.
Thus I have shown, as I proposed, that the author's reasoning proceeds on a false hypothesis. It supposeth testimony to derive its evidence solely from experience, which is: false. It supposeth by consequence, that contrary observations have a weight in opposing testimony, which the first and most acknowledged principles of human reason, or, if you like the term better, common sense, evidently shows that they have not. It assigns a rule for discovering the superiority of contrary evidences, which, in the latitude there given it, tends to mislead the judgment, and which it is imposa sible, by any explication, to render of real use,