Part I. Scientific and moral, with the principal distinctions between them,

eminence, denominated science; and the evidence itself is termed scientific; the result of this is frequently (not always) entitled to no higher denomination than opinion. Now, in the mathematical sciences, no mention is ever made of opinions.

THE third difference is, that in the one there never can be any contrariety of proofs; in the other, there not only may be, but almost always is. If one de. monstration were ever capable of being refuted, it could be solely by another demonstration, this being the only sort of evidence adapted to the subject, and the only sort by which the former could be matched. But, to suppose that contrarities are demonstrable, is to suppose that the same proposition is both true and false, which is a manifest contradiction. Consequently, if there should ever be the appearance of demonstration on opposite sides, that on one side must be fallacious and sophistical. It is not so with moral evidence, for unless in a few singular instances, there is always real, not apparent evidence on both sides. There are contrary experiences, contrary presumptions, contrary testimonies, to balance against one another. In this case, the probability, upon the whole, is in the proportion which the evidence on the side that preponderates bears to its opposite. We usually say, indeed, that the evidence lies on such a side of the question, and not on the reverse; but by this expression is only meant the overplus of evidence, on comparing both sides. In like manner, when we affirm of an event, that it is probable, we say the contrary is only

possible, although, when they are severally considered, we do not scruple to say, This is more probable than that; or, The probabilities on one side, outweigh those on the other.

THE fourth and last difference I shall observe is, that scientific evidence is simple, consisting of only one coherent series, every part of which depends on the preceding, and, as it were, suspends the following: moral evidence is generally complicated, being in reality a bundle of independent proofs. The longest demonstration is but one uniform chain, the links whereof, taken severally, are not to be regarded as so many arguments, and consequently, when thus taken, they conclude nothing; but, taken together, and in their proper order, they form one argument, which is perfectly conclusive. It is true, the same theorem may be demonstrable in different ways, and by different mediums; but as a single demonstration clearly understood, commands the fullest conviction, every other is superfluous. After one demonstrative proof, a man máy try a second, purely as an excercise of ingenuity, or the better to assure himself that he hath not committed an oversight in the first. Thus it may serve to warrant the regular procedure of his faculties, but not to make an addition to the former proof, or suply any deficiency perceived in it. So far is it from answering this end, that he is no sooner sensible of a defect in an attempt of this nature, than the whole is rejected as good for nothing, and carrying with it no degree of evidence whatever. In moral reasoning, on the con

Part I.....Scientific and moral, with the principal distinctions betweer, them.

trary, there is often a combination of many distinct topics of argument, noway dependent on one another. Each hath a certain portion of evidence belonging to itself, each bestows on the conclusion a particular degree of likelihood, of all which accumulated, the credibility of the fact is compounded. The former may be compared to an arch, no part of which can subsist independently of the rest. If you make any breach in it, you destroy the whole. The latter may be compared to a tower, the height whereof is but the aggregate of the heights of the several parts reared above one another, and so may be gradually diminished, as it was gradually raised.

So much for the respective natures of scientific and of moral evidence, and those characteristical qualities which discriminate them from each other. On a survey or the whole, it seems indubitable, that if the former is infinitely superior in point of authority, the latter no less excels in point of importance. Abstract truth, as far as it is the object of our faculties, is almost entirely confined to quantity, concrete or discrete. The sphere of Demonstration is narrow, but within her sphere she is a despotic sovereign, her sway, is uncontroulable, Her rival, on the contrary, hath less power, but wider empire. Her forces, in deed, are not always irresistable; but the whole world is comprised in her dominions. Reality or fact comprehends the laws and the works of nature, as well as the arts and the institutions of men; in brief, all the beings which fall under the cognizance of the human

mind, with all their modifications, operations, and effects. By the first, we must acknowledge, when applied to things, and combined with the discoveries of the second, our researches into nature in a certain line are facilitated, the understanding is enlightened, and many of the arts, both elegant and useful, are improved and perfected. Without the aid of the second, society must not only suffer, but perish. Human nature itself could not subsist. This organ of knowledge, which extends its influence to every precinct of philosophy, and governs in most, serves also to regulate all the ordinary, but indispensable concernments of life. To these it is admirably adapted, notwithstanding its inferiority in respect of dignity, accuracy, and perspicuity. For it is principally to the acquisitions procured by experience, that we owe the use of language, and the knowledge of almost every thing that makes the soul of a man differ from that of a new-born infant. On the other hand, there is no despot so absolute, as not be liable to a check on some side or other, and that the prerogatives of demonstration are not so very considerable, as on a cursory view one is apt to imagine; that this, as well as every other operation of the intellect, must partake in the weakness incident to all our mental faculties, and inseparable from our nature, I shall afterwards take an opportunity particulary to evince.

PART II...The nature and origin of Experience.

I SHOULD NOW consider the principal tribes compre,

Part II.

The nature and origin of experience.

hended under the general name of moral evidence: but, that every difficulty may be removed, which might retard our progress in the proposed discussion, it will be necessary, in the first place, to explore more accurately those sources in our nature, which give being to experience, and, consequently, to all those attainments, moral and intellectual, that are derived from it. These sources are two, sense and memory. The senses, both external and internal, are the original inlets of perception. They inform the mind of the facts which, in the present instant, are situated within the sphere of their activity, and no sooner discharge their office in any particular instance, than the articles of information exhibited by them, are devolved on the memory. Remembrance instantly succeeds sensation, insomuch that the memory becomes the sole repository of the knowledge received from sense; knowledge which, without this repository, would be as instantaneously lost as it is gotten, and could be of no service to the mind. Our sensations would be no better than the fleeting pictures of a moving object on a camera obscura, which leave not the least vestige behind them. Memory, therefore, is the original voucher extant, of those past realities for which we had once the evidence of sense. Her ideas are, as it were, the prints that have been left by sensible impressions. But, from these two faculties, considered in themselves, there results to us the knowledge only of individual facts, and only of such facts as either heretofore have come, or, at present, do come, under the notice of our senses.

VOL. I.