under consideration;-after which, we may proceed safely, in determining a priori what the result will be of any hypothetical combination of them, whether total or partial.*

These observations have led us to the same conclusion with that which forms the great outline of Bacon's plan of philosophizing; and which Newton has so successfully exemplified in his inquiries concerning gravitation and the properties of light. While they point out, too, the respective provinces and uses of the analytic and the synthetic methods, they illustrate the etymological propriety of the names by which, in the Newtonian School, they are contradistinguished from each other.

In fact, the meaning of the words analysis and synthesis, when applied to the two opposite modes of investigation in physics, is extremely analogous to their use in the practice of chemistry. The chief difference lies in this, that, in the former case, they refer to the logical processes of the understanding in the study of physical laws; in the latter, to the operative processes of the laboratory in the examination of material substances.

If the foregoing remarks are well founded, they lead to the correction of an oversight which occurs in the ingenious and elegant sketch of the History of Astronomy, lately published among the posthumous works of Mr. Smith; and which seems calculated to keep out of view, if not entirely to explode that essential distinction which I have been endeavouring to establish, between the inductive logic of Bacon's followers, and the hypothetical theories of their prede

cessors.

"Philosophy" (says Mr. Smith)" is the science of the connecting "principles of nature. Nature, after the largest experience that "common observation can acquire, seems to abound with events "which appear solitary and incoherent with all that go before them; "which therefore disturb the easy movement of the imagination; "which make its ideas succeed each other, if one may say so, by "irregular starts and sallies; and which thus tend, in some measure, "to introduce a confusion and distraction and giddiness of mind. "Philosophy, by representing the invisible chains which bind to"gether all these disjointed objects, endeavours to introduce order

“Itaque naturae facienda est prorsus solutio et separatio: non per ignem certe, sed per mentem tanquam ignem divinum "+ Nov. Organ. Lib II Aphor. xvi. The remainder of the aphorism is equally worthy of attention; in reading which, however, as well as the rest of Bacon's philosophical works, I must request, for a reason afterwards to be mentioned, that the word law may be substituted for form, wherever it may occur.-An at tention to this circumstance will be found of much use in studying the Novum Organon. A similar idea, under other metaphorical disguises, often occurs in Bacon. Considering the circumstances in which he wrote, logical precision was altogether impossible: yet it is astonishing with what force he conveys the spirit of the soundest philosophy of the eightteenth century "Neque enim in plano via sita est, sed ascendendo et descendendo; ascen dendo primo ad axiomata, descendendo ad opera." Nov. Org. Lib. i. Aphor. ciii.

[Therefore a solution and separation of nature is to be attempted, not certainly by fire, but by means of the understanding as a divine fire.]

[Neither is the path upon a plain surface but ascends and descends. Ascends to Axioms and descends to conclusions.]

"into this chaos of jarring and discordant appearances; to allay this "tumult of the imagination; and to restore it, when it surveys the "great revolutions of the universe, to that tone of tranquillity and composure, which is both most agreeable in itself, and most suita"ble to its nature. Philosophy, therefore, may be regarded as one "of those arts which address themselves to the imagination, by ren"dering the theatre of nature a more coherent, and, therefore, a 66 more magnificent spectacle, than otherwise it would have appear"ed to be."

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That this is one of the objects of philosophy, and one of the advantages resulting from it, I very readily admit. But, surely, it is not the leading object of that plan of inductive investigation which was recommended by Bacon, and which has been so skilfully pursued by Newton. Of all philosophical systems, indeed, hypothetical or legitimate, it must be allowed, that, to a certain degree, they both please the imagination and assist the memory, by introducing order and arrangement among facts, which had the appearance, before, of being altogether unconnected and isolated. But it is the peculiar and exclusive prerogative of a system fairly obtained by the method of induction, that, while it enables us to arrange facts already known, it furnishes the means of ascertaining, by synthetic reasoning, those which we have no access to examine by direct observation. The difference, besides, among hypothetical theories, is merely a difference of degree, arising from the greater or less ingenuity of their authors; whereas legitimate theories are distinguished from all others radically and essentially; and, accordingly, while the former are liable to perpetual vicissitudes, the latter are as permanent as the laws which regulate the order of the uni

verse.

Mr. Smith himself has been led by this view of the object of philosophy, into expressions concerning the Newtonian discoveries, which seem to intimate, that, although he thought them far superiour, in point of ingenuity, to any thing the world had seen before, yet, that he did not consider them as so completely exclusive of a still happier system in time to come, as the Newtonians are apt to imagine. "The system of Newton" (he observes) "now prevails " over all opposition, and has advanced to the acquisition of the "most universal empire that was ever established in philosophy. "His principles, it must be acknowledged, have a degree of firm66 ness and solidity that we should in vain look for in any other "system. The most sceptical cannot avoid feeling this. They "not only connect together most perfectly all the phenomena of the "heavens which had been observed before his time; but those "also which the persevering industry and more perfect instruments "of later astronomers have made known to us, have been either "easily and immediately explained by the application of his princi"ples, or have been explained in consequence of more laborious "and accurate calculations from these principles, than had been "instituted before. And even we, while we have been endeavour

"ing to represent all philosophical systems as mere inventions of the "imagination, to connect together the otherwise disjointed and dis"cordant phenomena of nature, have insensibly been drawn in to "make use of language expressing the connecting principles of "this one, as if they were the real chains which nature makes use "of, to bind together her several operations.

If the view which I have given of Lord Bacon's plan of investigation be just, it will follow, That the Newtonian theory of gravitation can, in no respect whatever admit of a comparison with those systems which are, in the slightest degree, the offspring of imagination; in as much as the principle employed to explain the phenomena is not a hypothesis, but a general fact established by induction; for which fact we have the very same evidence as for the various particulars comprehended under it. The Newtonian theory of gravitation, therefore, and every other theory which rests on a similar basis, is as little liable to be supplanted by the labours of future ages, as the mathematical conclusions of Euclid and Archimedes. The doctrines which it involves may be delivered in different, and perhaps less exceptionable forms; but, till the order of the universe shall be regulated by new physical laws, their substance must forever remain essentially the same. On the chains, indeed, which nature makes use of to bind together her several operations, Newton has thrown no light whatever; nor was it the aim of his researches to do so. The subjects of his reasonings were not occult connexions, but particular phenomena, and general laws; -both of them possessing all the evidence which can belong to facts ascertained by observation and experiment. From the one or the other of these all his inferences, whether analytical or synthetical, are deduced: Nor is a single hypothesis involved in his data, excepting the authority of that Law of Belief which it tacitly and necessarily assumed in all our physical conclusions,--The stability of the order of nature.

SECTION II.

Continuation of the Subject.-The Induction of Aristotle compared with that of Bacon.

In this section I intend to offer a few slight remarks upon an assertion which has been hazarded with some confidence in various late publications, that the method of investigation, so much extolled by the admirers of Lord Bacon, was not unknown to Aristotle.-It is thus very strongly stated by the ingenious author of a memoir in the Asiatic Researches.*

"From some of the extracts contained in this paper, it will appear, "1st, That the mode of reasoning by induction, illustrated and improved by the great Lord Verulam, in his Organum Novum, and

* Asiatic Researches, Vol. VIII. p. 89, 90. London Edition.

"generally considered as the cause of the rapid progress of science "in later times, was perfectly known to Aristotle, and was distinctly "delineated by him, as a method of investigation that leads to cer"tainty or truth: and 2dly, That Aristotle was likewise perfectly "acquainted, not merely with the form of induction, but with the pro66 per materials to be employed in carrying it on-facts and experi❝ments. We are therefore led to conclude, that all the blame of "confining the human mind for so long a time in chains, by the "force of syllogism, cannot be fairly imputed to Aristotle; nor all "the merit of enlarging it, and setting it free, ascribed to Lord "Verulam."

The memoir from which this passage is copied, consists of extracts translated (through the medium of the Persian) from an Arabic treatise entitled the Essence of Logic. When it was first presented to the Asiatic Society, the author informs us, that he was altogether ignorant of the coincidence of his own conclusions with those of Dr. Gillies; and he seems to have received much satisfaction from the subsequent perusal of the proofs alleged in support of their common opinion by that learned writer. "From the perusal "of this wonderful book (Dr. Gillies's exposition of the ethics and "politics of Aristotle) I have now the satisfaction to discover, that the "conjectures I had been led to draw from these scanty materials, "are completely confirmed by the opinion of an author, who is pro"bably better qualified than any preceding commentator on Aris"totle's works, to decide on this subject.'

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It is observed by Bailly in his History of Astronomy, that, although frequent mention is made of attraction in the writings of the ancients, we must not therefore "conclude that they had any pre"cise or just idea of that law into which Newton has resolved the "phenomena of the planetary revolutions. To their conceptions, "this word presented the notion of an occult sympathy between "different objects; and if any of them extended it from the de"scent of terrestrial bodies to explain the manner in which the moon was retained in her orbit, it was only an exhibition upon a "larger scale of the popular errour." The same author has remarked, on a different occasion, that, in order to judge of the philosophical ideas entertained at a particular period, it would be necessary to possess the dictionary of the age,-exhibiting the various shades of meaning derived from fashion or from tradition. "The import of words (he adds) changes with the times: their sig"nification enlarging with the progress of knowledge. Languages "are every moment perishing in detail from the variations intro"duced by custom: they grow old like those that speak them "and like them gradually alter their features and their form."‡

If this observation be just, with respect to the attraction of the ancients, when compared with the attraction of Newton, it will be found to apply with still greater force to the induction of Aristotle,* considered in contrast with the induction of Bacon.

It is well known to those who are at all conversant with Bacon's writings, that, although he borrowed many expressions from the scholastic phraseology then in vogue, he has, in general, not only employed them in new acceptations, consonant to the general spirit of his own logic, but has, by definitions or explanations, endeavoured to guard his readers against the mistakes to which they might be exposed, from a want of attention to the innovations thus introduced in the use of consecrated terms. How far he judged wisely in adopting this plan, (which has certainly much injured his style in point of perspicuity) I do not presume to decide; I wish only to state the fact:-his motives may be judged of from his own words.

"(1) Nobis vero ex altera parte (quibus, quantum calamo valemus, "inter vetera et nova in literis foedus et commercium contrahere, "cordi est) decretum manet, antiquitatem comitari usque ad aras; 66 atque vocabula antiqua retinere, quanquam sensum eorum et "definitiones saepius immutemus; secundum moderatum illum et “laudatum, in Civilibus, novandi modum, quo rerum statu novato "verborum tamen solennia durent; quod notat Tacitus; eadem "magistratuum vocabula."†

Of these double significations, so common in Bacon's phraseology, a remarkable instance occurs in the use which he makes of the scholastic word forms. In one passage, he approves of the opinion of Plato, that the investigation of forms is the proper object of science; adding, however, that this is not true of the forms which Plato had in view, but of a different sort of forms, more suited to the grasp of our faculties. In another passage, he observes, that when

Translated Inductio by Cicero.

De Aug. Scient. Lib. iii. Cap. iv.

The necessity under which the anti-Aristotelians found themselves, in the earlier part of the 17th century, of disguising their attack on the prevailing tenets, is strongly illustrated in a letter from Des Cartes to Regius. "Pourquoi rejettez-vous publiquement les qualités réelles et les formes substantielles, si cheres aux scholastiques: J'ai déclaré, que je ne prétendois pas les nier, mais que je n'en avois pas besoin pour expliquer mes pensées."

(Why do you publicly reject real qualities and "substantial forms? so dear to the disciples of the schools. I have declared that I do not pretend to deny them, but that I have no need of them to explain my thoughts.]

Manifestum est, Platonem, virum sublimis ingenii (quique veluti ex rupe excelsa omnia circumspiciebat) in sua de ideis doctrina, formas esse verum scientiae objectum, vidisse ; utcunque sententiae hujus verissimae fructum amiserit, formas penitus à materia abstractas,

(1) [But for myself, as I am desirous, as far as lies within the ability of my pen, to make a treaty of alliance and commerce between the old and new schools of philosophy and letters, I have determined to accompany antiquity even to the altar, and to retain terms of estab lished usage, although I should often vary them in sense and definition; according to that moderate and laudable custom of innovation by Civilians, that when a new state of affairs is introduced, the accustomed terms should remain. So Tacitus, The offices were distinguished by the same names.]

VOL. II.

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