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would not chuse to recommend it, except in a desperate case; and would then consider its success as a thing rather to be wished than expected. An equal number of favourable and unfavourable instances leave the mind in a state of suspense, without exciting the smallest degree of assurance on either side, except, perhaps, what may arise from our being more interested on the one side than on the other. A physician influenced by such evidence would say, "My patient may recover, and he may "die I am sorry to say, that the former event is "not one whit more probable than the latter." When the favourable instances exceed the unfavourable in number, we begin to think the future event in some degree probable; and more or less so, according to the surplus of favourable instances. A few favourable instances, without any mixture of unfavourable ones, render an event probable in a pretty high degree: but the favourable experience must be at once extensive and uniform, before it can produce moral certainty.

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A man brought into being at maturity, and placed in a desert island, would abandon himself to despair, when he first saw the sun set, and the night come on; for he could have no expectation that ever the day would be renewed. But he is transported with joy, when he again beholds the glorious orb appearing in the east, and the heavens and the earth illuminated as before. He again views the declining sun with apprehension, yet not without hope; the second night is less dismal than the first, but is still very uncomfortable on account of the weakness the probability produced by one favourable ins. nce. As the instances grow more numerous, the probabili

ty becomes stronger and stronger; yet it may be questioned, whether a man in these circumstances would ever arrive at so high a degree of moral certainty in this matter, as we experience; who know, not only that the sun has risen every day since we began to exist, but also that the same phenomenon has happened regularly for more than five thousand years, without failing in a single instance. The judgment of our great epic poet appears no where to more advantage than in his eighth book; where Adam relates to the angel what passed in his mind immediately after his awaking into life. The following passage is at once transcendently beautiful, and philosophically just :

"While thus I call'd, and stray'd I knew not whither,
"From where I first drew air, and first beheld
"This happy light, when answer none return'd,
"On a green shady bank, profuse of flowers,
"Pensive I sat me down; there gentle sleep
"First found me, and with soft oppression seiz'd
"My droused sense; untroubled, though I thought
"I then was passing to my former state
"Insensible, and forthwith to dissolve *""

Paradise Lost, b. viii. 1. 283.

Adam at this time had no experience of sleep, and therefore could not, with any probability, expect that he was to recover from it. Its approaches were attended with feelings similar to those he had experienced when awaking from non-existence, and would naturally suggest that idea to his mind; and as he had no reason to expect that his life was to continue, would intimate the probability that he was again upon the verge of an insensible state.

*The beauty of these lines did not escape the elegant and judicious Addison; but that author does not assign the reason of his approbation. Spect. No 345.

Now it is evident, from what has been already said, that the degree of probability must be intuitively perceived, or the degree of assurance spontaneously and instinctively excited in the mind, upon the bare consideration of the instances on either side; and that without any medium of argument to connect the future event with the past experience. Reasoning may be employed in bringing the instances into view; but when that is done, it is no longer necessary. And if you were to argue with a man, in order to convince him that a certain future event is not so improbable as he seems to think, you would only make him take notice of some favourable instance which he had overlooked, or endeavour to render him. suspicious of the reality of some of the unfavourable instances; leaving it to himself to estimate the degree of probability. If he continue refractory, notwithstanding that his view of the subject is the same with yours, he can be reasoned with in no other way, than by your appealing to the common sense of mankind.

SECT. VII.

Of Analogical Reasoning.

EASONING from analogy, when traced up to its source, will be found in like manner to terminate in a certain instinctive propensity, implanted in us by our Maker, which leads us to expect, that similar causes in similar circumstances, do probably produce, or will probably produce, similar effects. The probability which this kind of evidence is fitted to illustrate, does, like the former, admit of a vast variety of degrees, from absolute doubting, up to moral certainty. When the ancient philosopher

who was shipwrecked in a strange country, discovered certain geometrical figures drawn upon the sand by the sea-shore, he was naturally led to believe, with a degree of assurance not inferior to moral certainty, that the country was inhabited by men, some of whom were men of study and science, like himself. Had these figures been less regular and liker the appearance of chance-work; the presumption from analogy, of the country being inhabited, would have been weaker; and had they been of such a nature as left it altogether dubious, whether they were the work of accident or of design, the evidence would have been too ambiguous to serve as a foundation for any opinion.

In reasoning from analogy, we argue from a fact, or thing experienced to something similar not experienced; and from our view of the former arises an opinion with regard to the latter; which opinion will be found to imply a greater or less degree of assurance, according as the instance from which we argue is more or less similar to the instance to which we argue. Why the degree of our assurance is determined by the degree of likeness, we cannot tell; but we know by experience, that this is the case: and by experience also we know, that our assurance, such as it is, arises immediately in the mind, whenever we fix our attention on the circumstances in which the probable event is expected, so as to trace their resemblance to those circumstances in which we have known a similar event to take place. A child who has been burnt with a red-hot coal, is careful to avoid touching the flame of a candle; for as the visible qualities of the latter are like to those of the former, he expects, with a very high degree of assurance, that

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the effects produced by the candle operating on his fingers, will be similar to those produced by the burning coal. And it deserves to be remarked, that the judgment a child forms on these occasions may arise, and often doth arise, previous to education and reasoning, and while experience is very limited. Knowing that a lighted candle is a dangerous object, he will be shy of touching a glow-worm, or a piece of wet fish shining in the dark, because of their resemblance to the flame of a candle; but as this resemblance is but imperfect, his judgment, with regard to the consequences of touching these objects, will probably be more inclined to doubt, than in the former case, where the instances were more similar.

Those who are acquainted with astronomy, think it extremely probable, that the planets are inhabited by living creatures, on account of their being in all other respects so like to our earth. A man who thinks them not much bigger than they appear to the eye, never dreams of such a notion; for to him they seem in every respect unlike to our earth and there is no other way of bringing him over to the astronomer's opinion, than by explaining to him those par ticulars in which the planets and our earth resemble one another. As soon as he comprehends these particulars, and this resemblance, his mind of its own accord admits of the probability of the new opinion, without being led to it by any medium of proof, connecting the facts he hath experienced with other similar and probable facts lying beyond the reach of his experience. Such a proof indeed, could not be given. If he were not convinced of the probability by the bare view of the facts, you would impute his perseverance in his old opinion, either to obstinacy, or to

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