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philosophy: and something extremely analogous to it in all our conclusions concerning human affairs. They relate, in both cases, not to necessary connexions, but to probable or contingent events; of which, how confidently soever we may expect them to take place, the failure is by no means perceived to be impossible. Such conclusions, therefore differ essentially from those to which we are led by the demonstrations of pure mathematics, which not only command our assent to the theorems they establish, but satisfy us that the contrary suppositions are absurd.

These examples may suffice to convey a general idea of the distinction between demonstrative and probable evidence; and I purposely borrowed them froin sciences where the two are brought into immediate contrast with each other, and where the authority of both has hitherto been equally undisputed.

Before prosecuting any farther the subject of probable evidence, some attention seems to be due, in the first place, to the grounds of that fundamental supposition on which it proceeds,—the stability of the order of nature. of this important subject, accordingly, I propose to treat at some length. II.- Continuation of the Subject. Of the Permanence or Stability

in the Order of Nature, which is presupposed in our Reasonings concerning Contingent Truths.

I have already taken notice of a remarkable principle of the mind, (whether coeval with the first exercise of its powers, or the gradual result of habit, it is not at present material to inquire,) in consequence of which we are irresistibly led to apply to future events, the results of our past experience. In again resuming the subject, I do not mean to add any thing to what was then stated concerning the origin or the nature of this principle ; but shall confine myself I to a few reflections on that established order in the succession of events, which it unconsciously assumes as a fact; and which, if it were not real, would render human life a continued series of errors and disappointments. In any incidental remarks that may occur on the principle itself, I shall consider its existence as a thing universally acknowledged, and shall direct my attention chiefly 10 jis practical effects ;-effects which will be found to extend equally to the theories of the learned, and to the prejudices of the vulgar. The question with regard to its origin is, in truth, a problem of mere curiosity; for of its actual influence on our belief and on our conduct, no doubts have been suggested by the most sceptical writers.

Before entering, however, upon the following argument, it may not be superfluous to observe, with respect to this expectation, that in whatever manner it at first arises, it cannot fail to be mightily confirmed and strengthened by habits of scientific research ; the tendency of which is to familiarise us more and more with the simplicity and the uniformity of physical laws by gradually reconciling with them, as our knowledge extends, those phenoinena which we had previously been disposed to consider in the light of exceptions. It is thus that, when due allowances are made for the different cir cumstances of the two events, the ascent of smoke appears to be no less a proof of the law of gravitation than the fall of a stone. This simplification and generalization of the laws of nature is one of the greatest pleasures which philosophy yields ; and the growing confidence with which it is anticipated, forms one of the chief incentives to philosophical pursuits. Few experiments, perhaps, in physics, afford more exquisite delight to the novice, or throw a stronger light on the nature and object of that science, than when he sees, for the first time, the guinea and the feather drop together in the exhausted receiver.

In the language of modern science, the established order in the succession of physical events is commonly referred (by a sort of figure or metaphor) to the general laws of nature. It is a mode of speaking extremely convenient from its conciseness, but is apt to suggest to the fancy a groundless, and indeed absurd analogy between the material and the moral words. As the order of society results from the laws prescribed by the legislator, so the order of the universe is conceived to result from certain laws established by the Deity. Thus, it is customary to say, that the fall of heavy bodies towards the earth's surface, the ebbing and flowing of the sea, and the motions of the planets in their orbits, are consequences of the law of gravitation. But although, in one sense, this may be abundantly accurate, it ought always to be kept in view, that it is not a literal but a metaphorical statement of the truth ; a statement somewhat analogous to that poetical expression in the sacred writings, in which God is said “to have given his decree to the seas, that they should not pass his commandment.” In those political associations from which the metaphor is borrowed, the laws are addressed to rational and voluntary agents, who are able to comprehend their meaning, and to regulate their conduct accordingly ; whereas, in the material universe, the subjects of our observation are understood by all men to be unconscious and passive, (that is, are understood to be unchangeable in their state, without the influence of some foreign and external force,) and consequently the order so admirably maintained, amidst all the various changes which they actually undergo, not only implies intelligence in its first con- ? ception, but implies, in its continued existence, the incessant agency of power, executing the purposes of wise design. If the word law, therefore, be, in such instances, literally interpreted, it must mean a uniform mode of operation, prescribed by the Deity to himself ; and it has accordingly been explained in this sense by some of our best philosophical writers, particularly by Dr. Clarke.* In employSo likewise Halley in his Latin verses prefixed to Newton's Principia ;

“En tibi norma poli, et divæ libramina molis,

ing, however, the word with an exclusive reference to experimental philosophy, it is more correctly logical to consider it as merely a statement of some general fact with respect to the order of nature; a fact which has been found to hold uniformly in our past experience, and of the continuance of which, in future, the constitution of our mind determines us confidently to rely.

After what has been already said, it is hardly necessary to take notice of the absurdity of that opinion, or rather of that mode of speaking, which seems to refer the order of the universe to general laws operating as efficient causes. Absurd, however, as it is, there is reason to suspect, that it has, with many, had the effect of keeping the Deity out of view, while they were studying his works. To an incautious use of the same very equivocal phrase, may be traced the bewildering obscurity in the speculations of some eminent French writers, concerning its metaphysical import. Even the great Montesquieu, in the very first chapter of his principal work, bas lost himself in a fruitless attempt to explain its meaning, when, by a simple statement of the essential distinction between its literal and its metaphorical acceptations, he might have at once cleared up the mystery. After telling us that “ laws, in their most extensive signification, are the necessary relations (les rapports nécessaires) which arise from the nature of things, and that, in this sense, all beings have their laws ;—that the Deity has his laws; the material world its laws; intelligences superior to man their laws; the brutes their laws; man his laws;" he proceeds to remark, “ That the moral world is far from being so well governed as the material ; for the former, although it has its laws, which are invariable, does not observe these laws so constantly as the latter.” It is evident that this remark derives whatever plausibility it possesses from a play upon words ; from confounding moral laws with physical; or, in plainer terms, froin confounding laws which are addressed by a legislator to intelligent beings, with those general conclusions concerning the established order of the universe, to which, when legitimately inferred from an induction sufficiently extensive, philosophers have metaphorically applied the title of Laws of Nature. In the one case, the conformity of the law with the nature of things, does not at all depend on its being observed or not, but on the reasonableness and moral obligation of the law. In the other case, the very definition of the word law supposes that it applies universally; inasmuch that, if it failed in one single instance, it would cease to be a law. It is, therefore, a mere quibble to say, that the laws of the material world are better observed than those of the moral; the meaning of the word law, in the two cases to which it is here applied, being so totally different, as to render the comparison or contrast, in the statement of which it is involved, altoge

Computus en Jovis; et quas, dum primordia rerum
Pangeret, omniparens leges violare Creator

ther illusory and sophistical. Indeed, nothing more is necessary to strip the proposition of every semblance of plausibility, but an attention to this verbal ambiguity.*

This metaphorical employment of the word law, to express a general fact, although it does not appear to have been adopted in the technical phraseology of ancient philosophy, is not unusual among the classical writers, when speaking of those physical arrangements, whether on the earth or in the heavens, which continue to exhibit the same appearance from age to age.

“ Hic segetes, illic veniunt felicius uvæ :

Arborei fetus alibi, atque injussa virescunt
Gramina. Nonne vides, croceos ut Tmolus odores,
India mittit ebur, molles sui thura Sabæi?
At Chalybes nudi ferruin, virosaque Pontus
Castorea, Eliadum palmas Epiros equarum?
Continuo has leges, æternaque fædera certis
Imposuit natura locis.”— Virg. i. Georg. 60.

The same metaphor occurs in another passage of the Georgics, where the poet describes the regularity which is exhibited in the economy of the bees:

“ Solæ communes natos, consortia tecta
Urbis habent, magnisque agitant sub legibus ævum."

Georg. iv. 153.

The following lines from Ovid's account of the Pythagorean philosophy, are still more in point :

“ Et rerum causas, et quid natura docebat;

Quid Deus : Unde nives : quæ fulminis esset origo :
Jupiter, an venti, discussa nude tonarent:
Quid quateret terras, quâ sidera lege mearent,
Et quodcunque latet."'1-Ovid. Met. xv. 68.

* I do not recollect any instance in the writings of Montesquieu, where he has reasoned more vaguely than in this chapter; and yet I am inclined to believe, that few chapters in the Spirit of Laws have been more admired. “Montesquieu, says a French writer, “ paroissoit à Thomas le premier des écrivans, pour la force et l'étendue des idées, pour la multitude, la profondeur, la nouveauté des rapports. Il est incroyable (disoit-il) tout ce que Montesquieu a fait apperçevoir dans ce mot si court, le mot Loi.”—Nouveau Diction. Historique, Art. Thomas. Lyon, 1804.

For some important remarks on the distinction between moral and physical laws, see Dr. Ferguson's Institutes of Moral Philosophy, last edit.

+ I shall only add to these quotations the epigram of Claudian on the instrument said to be invented by Archimedes for representing the movements of the heavenly bodies, in which various expressions occur coinciding remarkably with the scope of the foregoing observations.

“ Jupiter in parvo cum cerneret æthera vitro

Risit, et ad superos talia dicta dedit.
Huccine mortalis progressa potentia curæ;

Jam meus in fragili luditur orde labor.
Jura Poli, rerumque fidem, legesque Deorum

Ecce Syracusius transtulit arte senex.
Inclusus variis famulatur spiritus astris,

Et vivum certis motibus urget opus.

I have quoted these different passages from ancient authors, chiefly as an illustration of the strength and of the similarity of the impression which the order of nature has made on the minds of reflecting men, in all ages of the world. Nor is this wonderful; for, were things differently constituted, it would be impossible for man to derive benefit from experience; and the powers of observation and memory would be subservient only to the gratification of an idle curiosity. Io consequence of those uniform laws by which the succession of events is actually regulated, every fact collected with respect to the past is a foundation of sagacity and of skill with respect to the future ; and, in truth, it is chiefly this application of experience to anticipate what is yet to happen, which forms the intellectual superiority of one individual over another. The remark holds equally in all the various pursuits of mankind, whether speculative or active. As an astronomer is able, by reasonings founded on past observations, to predict those phenomena of the heavens which astonish or terrify the savage:-as the chemist, from his previous familiarity with the changes operated upon bodies by heat or by mixture, can predict the result of innumerable experiments, which to others furnish only matter of amusement and wonder ;-—so a studious observer of human affairs acquires a prophetic foresight (still more incomprehensible to the multitude) with respect to the future fortunes of mankind ;—a foresight which, if it does not reach, like our anticipations in physical science, to particular and definite events, amply compensates for what it wants in

precision, by the extent and variety of the prospects which it opens. ? It is from this apprehended analogy between the future and the

past, that historical knowledge derives the whole of its value; and were the analogy completely to fail, the records of former ages would, in point of utility, rank with the fictions of poetry. Nor is the case different in the business of common life. Upon what does the success of men in their private concerns so essentially depend as on their own prudence: and what else does this word

Percurrit proprium mentitus signifer annum,

Et simulata novo Cynthia mense redit.
Jamque suum volvens audax industria mundum

Gaudet, et humana Sydera mente regit.
Quid falso insontem tonitru Salmonea miror ?
Æmula naturæ parva reperta manus."

In the progress of philosophical refinement at Rome, this metaphorical applica. tion of the word law seems to have been attended with the same consequences which, as I already observed, have resulted from an incautious use of it among some philosophers of modern Europe. Pliny tells us, that, in his time, these consequences extended both to the lettered, and to the unlettered multitude. " Pars alia astro suo eventus assignat, et nascendi legibus; semelque in omnes futuros unquam Deo decretum, in reliquum vero otium datum. Sedere cæpit sententia hæc, pariterque et eruditum vulgus et rude in eam cursu vadit.”—Plin. Nat, Hist. Lib. ii.

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