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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 strength of the reasoning, sometimes approaches to certainty, sometimes is 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 reasoning. When Inigo Jones flourished and was the only architect of note in England ; let it be supposed, that his model of the palace of Whitehall 'had been presented to a stranger, without mentioning the author. The stranger, in the first place, would be intuitively certain, that this was the work of some Being, intelligent and skilful. 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 less firm than the former. Let us next suppose another English architect little inferior in reputation to Jones ; the stranger would still pranounce in favour of the latter ; but his belief would be in the lowest degree.



When we investigate the causes of certain effects, the reasoning 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 houses, without any fence to secure them from theft : whence it is rationally inferred, that coals are there in plenty. In the west of Scotland, the corn-stacks 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 circumstance it is conjectured, that the Biscayners were the first Europeans who made a settlement in that illand.

Analogical reasoning, founded uniformity of nature, is frequently employ'd in the investigation of facts; and we infer, that facts of which we are uncertain, must resemble those of the same kind that are known. The reasonings in natural philosophy are mostly of that kind. Take the following examples. We learn from experience, that proceeding from the humbleft vegetable to man, there are nun



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berless classes of beings rifing one above another by differences fcarce perceptible, and leaving no where a single 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 Every man: is confcious of a self-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 same argument to other animals; tha’ their resemblance to man appears not so certain, as that of one man to another. But why not also apply the same 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 boru rod'd from Maupertuis. As there is no "known space of the earth covered with $ water so large as the Terra Australis in16. cognita, we may reasonably infer, thay

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" so great a part of the earth is not alto

gether fea, but that there must be some proportion of land. The uniformity

90 of nature with respect to the intermixture of sealand land, is an argument that affords but a very slender degree of conviction ; land from late voyages it is discovered, that the argument holds not in fact, The following argument of the fame kind, tho' it cannot be much rely'd on, seems however better founded. 1.“ The inhabi"tants of the northern hemifphere, have,

in arts and sciences, excelled such of the “ fouthern as we have any knowledge of: and therefore among

the latter we ought not to expect many arts, nor much cultivation."

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 succinct recapitulation.

We have two means for discovering truth and acquiring knowledge, viz. intuition and reasoning. By intuition we difcover subjects and their attributes, paslions, internal action, and in short every thing that is matter of fact. By intuition we also discover several relations. There are some facts and many relations, that cannot be discovered by a single act of intuition, but require several such acts linked together in a chain of reasoning.


Knowledge acquired by intuition, includes for the most part certainty : in some instances it includes probability only. Knowledge acquired by reasoning, 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.

Reasoning that produces certainty, is termed denonstrative; and is termed probable, when it only produces probability.

Demonstrative reasoning is of two kinds. The first is, where the conclusion is derived from the nature and inherent properties of the subject: mathematical reason• ing is of that kind ; and perhaps the only inítance. The second is, where the conclusion is derived from some proposition, of which we are certain by intuition.


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