Human teftimony, the third caufe, produces beFief, more or lefs ftrong, according to circumftances. In general, nature leads us to rely upon the veracity of each other; and commonly the degree of reliance is proportioned to the degree of veracity. Sometimes belief approaches to a certainty, as when it is founded on the evidence of perfons above exception as to veracity. Sometimes it finks to the loweft degree of probability, as when a fact is told by one who has no great reputation for truth. The nature of the fact, common or uncommon, has likewife an influence: an ordinary incident gains credit upon very flight evidence; but it requires the ftrongest evidence to overcome the improbability of an event that deviates from the ordinary courfe of nature, At the fame time, it must be observed, that belief is not always founded upon rational principles. There are biaffes and weakneffes in human nature that fometimes difturb the operation, and produce belief without fufficient or proper evidence: we are difpofed to believe on very flight evidence, an interefting event, however rare or fingular, that alarms and agitates the mind; becaufe the mind in agitation is remarkably fufceptible of impreffions for which reafon ftories of ghofts and apparitions pafs current with the vulgar. Eloquence alfo has great power over the mind; and, by making deep impreffions, enforces the belief of facts upon evidence that would not be regarded in a cool moment.

The dependence that our perception of real exiftence, and confequently belief, hath upon oral evidence, enlivens focial intercourfe, and promotes fociety. But the perception of real existence has a ftill more extenfive influence; for from that perception is derived a great part of the entertainment we find in hiftory, and in historical fables (a).

(a) Elements of Criticism, ch. 2. part 1. § 7.

At

At the fame time, a perception that may be raised by fiction as well as by truth, would often miflead were we abandoned to its impulfe: but the God of nature hath provided a remedy for that evil, by erecting within the mind a tribunal, to which there lies an appeal from the rafh impreffions of fenfe. When the delufion of eloquence or of dread fubfides, the perplexed mind is uncertain what to believe. A regular procefs commences, counfel is heard, evidence produced, and a final judgement pronounced, fometimes confirming, fometimes varying, the belief impreffed upon. us by the lively perception of reality. Thus, by a wife appointment of nature, intuitive belief is fubjected to rational difcuffion: when confirmed by reason, it turns more vigorous and authoritative: when contradicted by reafon, it disappears among fenfible people. In fome inftances, it is too headftrong for reafon; as in the cafe of hobgoblins and apparitions, which pafs current among the vulgar in fpite of reason.

We proceed to the other kind of belief, that which is founded on reafoning; to which, when intuition fails us, we must have recourfe for afcertaining facts. Thus, from known effects, we infer the existence of unknown caufes. That an effect must have a caufe, is an intuitive propofition; but to afcertain what particular thing is the cause, requires commonly a procefs of reafoning. This is one of the means by which the Deity, the primary caufe, is made known to us, as mentioned above. Realon, in tracing caufes from known effects, produces different degrees of conviction. It fometimes produces certainty, as in proving the existence of the Deity; which on that account is handled above, under the head of knowledge. For the most part it produces belief only, which, according to the ftrength of the reafoning, fometimes approaches to certainty fometimes is

fo

fo weak as barely to turn the fcale on the fide of probability. Take the following examples of different degrees of belief founded on probable reafoning. When Inigo Jones flourished and was the only architect of note in England; let it be fupposed, that his model of the palace of Whitehall had been prefented to a' ftranger, without mentioning the author. The ftranger, in the firft place, would be intuitively certain, that this was the work of fome Being, intelligent and fkilful. Secondly, He would have a conviction approaching to certainty, that the operator was a man. And, thirdly, He would have a conviction that the man was. Inigo Jones; but lefs firm than the former. Let us next fuppofe another English architect little inferior in reputation to Jones: the ftranger would ftill pronounce in favour of the latter; but his belief would be in the lowest degree.

When we inveftigate the caufes of certain effects, the reafoning is often founded upon the known nature of man. In the high country, for example, between Edinburgh and Glasgow, the people lay their coals at the end of their houfes, without any fence to fecure them from theft: whence it is rationally inferred, that coals are there in plenty. In the weft of Scotland, the corn-ftacks are covered with great care and nicety: whence it is inferred, that the climate is rainy. Placentia is the capital town of Biscay: the only town in Newfoundland bears the fame name; from which circumftance it is conjectured, that the Bifcayners were the first Europeans who made a fettlement in that island.

Analogical reafoning, founded upon the uniformity of nature, is frequently employed in the inveftigation of facts; and we infer, that facts of which we are uncertain, muft refemble those of the fame kind that are known. The reasonings in natural philosophy are mostly of that kind. Take

Take the following examples. We learn from experience, that proceeding from the humblest vege table to man, there are numberless claffes of beings rifing one above another by differences fcarce perceptible, and leaving no where a fingle gap or interval and from conviction of the uniformity of nature we infer, that the line is not broken off here, but is carried on in other worlds, till it end in the Deity. I proceed to another example. Every man is confcious of a felf-motive power in himself; and from the uniformity of nature, we infer the fame power in every one of our own fpecies. The argument here from analogy carries great weight, because we entertain no doubt of the uniformity of nature with respect to beings of our own kind. We apply the fame argument to other animals; though their refemblance to man appears not fo certain, as that of one man to another. But why not also apply the fame argument to infer a felf-motive power in matter? When we fee matter in motion without an external mover, we naturally infer, that, like us, it moves itself. Another example is borrowed from Maupertuis." As there is no known fpace of the "earth covered with water fo large as the Terra Auftralis incognita, we may reasonably infer, that "fo great a part of the earth is not altogether fea, "but that there must be fome portion of land." The uniformity of nature with refpect to the intermixture of fea and land, is an argument that affords but a very flender degree of conviction; and from late voyages it is discovered, that the argument holds not in fact. The following argument of the fame kind, though it cannot be much relied on, feems however better founded. The inhabitants of the "northern hemifphere, have, in arts and fciences, "excelled fuch of the fouthern as we have any "knowledge of: and therefore among the latter "we ought not to expect many arts, nor much cul"tivation." VOL. II.

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After

After a fatiguing investigation of numberless particulars which divide and scatter the thought, it may not be unpleasant to bring all under one view by a fuccinct recapitulation.

We have two means for discovering truth and acquiring knowledge, viz. intuition and reafoning. By intuition we difcover fubjects and their attributes, paffions, internal action, and in fhort every thing that is matter of fact. By intuition we alfo difcover feveral relations. There are fome facts and many relations, that cannot be difcovered by a fingle act of intuition, but require feveral fuch acts linked together in a chain of reafoning.

Knowledge acquired by intution, includes for the most part certainty: in fome inftances it includes probability only. Knowledge acquired by reafoning, frequently includes certainty; but more frequently includes probability only.

Probable knowledge, whether founded on intuition or on reasoning, is termed opinion when it concerns relations; and is termed belief when it concerns facts. Where knowledge includes certainty, it retains its proper name.

Reafoning that produces certainty, is termed demonftrative; and is termed probable, when it only produces probability.

Demonstrative reafoning is of two kinds. The firft is, where the conclufion is derived from the nature and inherent properties of the fubject: mathematical reasoning is of that kind; and perhaps the only inftance. The fecond is, where the conclufion is derived from fome propofition, of which we are certain by intuition.

Probable reafoning is endless in its varieties; and affords different degrees of conviction, depending on the nature of the fabject upon which it is employed.

SECT.