hand, it must be acknowledged, that this part of Aristotle's works contains some intrinsic evidence of aid borrowrd from a more ancient school. Besides that imposing appearance which it exhibits of systematical completeness in its innumerable details; and which we can scarcely suppose that it could have received from the original inventor of the art, there is a want of harmony or unity in some of its fundamental principles, which seems to betray a combination of different and of discordant theories. I allude more particularly to the view which it gives of the nature of science and of demonstration, compared with Aristotle's well-known opinions concerning the natural progress of the mind in the acquisition of knowledge. That the author of the Organon was fully aware of an incongruity so obvious, there can be little doubt; and it was not improbably with a view to disguise or to conceal it, that he was induced to avoid, as much as possible, every reference to examples; and to adopt that abstract and symbolical language, which might divert the attention from the inanity of his demonstrations, by occupying it in a perpetual effort to unriddle the terms in which they are expressed.

Nor does there seem to be any thing in these suggestions (which I hazard with much diffidence) inconsistent with Aristotle's own statement, in the concluding chapter of the book of sophisms. This chapter has indeed (as far as I know) been universally understood as advancing a claim to the whole art of syllogism; but I must acknowledge, that it appears to me to admit of a very fair construction, without supposing the claim to comprehend all the conformément aux principes du Lycée, auxquels ils s'attachent si fort, qu' Averroes, Alfarabius, Albumassar, et assez d'autres philosophes Arabes se sont souvent éloignés des sentiments de leur prophête, pour ne pas contredire ceux d'Aristote, que les Turcs ont en leur idiome Turquesque et en Arabe, comme Belon la rapporte."-La Motte le Vayer; quoted by Bayle, art. Aristote.

"L'Auteur, dont j'emprunte ces paroles, dit dans un autre volume, que, selon la relation d'Olearius, les Perses ont toutes les œuvres d'Aristote, expliquées par beaucoup de commentaires Arabes. Bergeron (dit il) remarque, dans son Traité des Tartares, qu'ils possedent les livres d'Aristote, traduits en leur langue, enseignant, avec autant de soumission qu'on peut faire ici, sa doctrine à Samarcand, université du Grande Mogol, et à présent ville capitale du royaume d'Usbec.'

In the eight volume of the Asiatic Researches, there is a paper by Dr. Balfour, containing some curious extracts (accompanied with an English version) from a Persian translation of an Arabic treatise, entitled the "Essence of Logic." In the introduction to these extracts, Dr. Balfour mentions it as an indisputable fact that "the system of logic, generally ascribed to Aristotle, constitutes, at this time, the logic of all the nations of Asia who profess the Mahomedan faith; and it seems to have been with a view of rendering this fact still more palpable to comnon readers, that the author has taken the trouble to translate, through the medium of the Persian, the Arabic original; from which language the knowledge of Aristotle's logic, possessed by the orientals, is supposed to have been derived. * "The conclusion of this treatise," the book of Sophisms, "ought not to be overlooked; it manifestly relates, not to the present treatise only, but also to the whole Analytics and Topics of the author."-Reid's Analysis, &c. chap. v.

sec. iii.

If I were satisfied that this observation is just, I should think that nothing short of the most irresistible evidence could be reasonably opposed to the direct assertion of Aristotle. It is quite inconceivable, that he should have wilfully concealed or misrepresented the truth, at a period when there could not fail to be many philosophers in Greece, both able and willing to expose the deception.

doctrines delivered in the books of Analytics. In support of this idea, it may be remarked, that while Aristotle strongly contrasts the dialectical art, as taught in the preceding treatise, with the art of disputation as previously practised in Greece, he does not make the slightest reference to the distinction between demonstrative and dialectical syllogisms, or to those doctrines with respect to demonstration and science, which accord so ill with the general spirit of his philosophy. It does not seem, therefore, to be a very unreasonable supposition, that to these doctrines, (with which for many rea sons he might judge it expedient to incorporate his own inventions and innovations,) he only gave that systematical and technical form, which, by its peculiar phraseology and other imposing appendages, was calculated at once to veil their imperfections, and to gratify the vanity of those who should make them objects of study. It is surely not impossible, that the syllogistic theory may have existed as a subject of abstract speculation, long before any attempt was made to introduce the syllogism into the schools as a weapon of controversy, or to prescribe rules for the skillful and scientific ma nagement of a vivá voce dispute.

It is true that Aristotle's language, upon this occasion, is somewhat loose and equivocal; but it must be remembered, that it was addressed to his contemporaries, who were perfectly acquainted with the real extent of his merits as an inventor; and to whom, accordingly, it was not necessary to state his pretensions in terms more definite and explicit.

I shall only add, that this conjecture, supposing it for a moment to be sanctioned by the judgment of the learned, would still leave Aristotle in complete possession of by far the most ingenious and practical part of the scholastic logic; while, at the same time,should future researches verify the suspicions of Sir William Jones and others, that the first rudiments of the art were imported into Greece from the East, it would contribute to vindicate his character against the charge of plagiarism, and of unfairness towards his predecessors, which has been admitted even by some who

This was plainly the opinion of Cicero: "In hac arte," he observes, speaking of the dialectical art, as it was cultivated by the Stoics," in hac arte, si modo est hæc ars, nullum est præceptum quomodo verum inveniatur, sed tantum est quomodo judicetur." And a few sentences after; "Quare istam artem totam dimittamus, quæ in excogitandis argumentis muta nimium est, in judicandis nimium loquax.' (De Orat. lib. ii. 86, $7.) The first sentence is literally applicable to the doctrine of syllogism considered theoretically: the second contrasts the inutility of this doctrine with the importance of such subjects as are treated of in Aristotle's Topics.

Whether Cicero and Quinctilian did not overrate the advantages to be derived from the study of the Loci as an organ of invention, is a question altogether foreign to our present inquiries. That it was admirably adapted for those argumentative and rhetorical displays which were so highly valued in ancient times, there can be no doubt, after what these great masters of oratory have written on the subject; but it does not follow, that, in the present state of society, it would reward the labors of those who wish to cultivate either the eloquence of the bar, or that which leads to distinction in our popular assemblies.

speak with the most unbounded reverence of his intellectual endowments.

From the logic of Aristotle, I now proceed to that of Lord Bacon; a logic which professes to guide us systematically in investigating the laws of nature, and in applying the knowledge thus acquired, to the enlargement of human power, and the augmentation of human happiness.

Of some of the fundamental rules by which this mode of philosophizing is more peculiarly distinguished, I intend to treat at considerable length;-directing my attention chiefly to such questions as are connected with the theory of our intellectual faculties. In this point of view, the author has left much to be supplied by his successors; the bent of his own genius having fortunately determined him rather to seize, by a sort of intuitive penetration, great practical results, than to indulge a comparatively sterile curiosity, by remounting to the first sources of experimental knowledge in the principles and laws of the human frame. It is to this humbler task that I propose to confine myself in the sequel. To follow him through the details of his Method, would be inconsistent with the nature of my present undertaking.

CHAPTER IV.

OF THE METHOD OF INQUIRY POINTED OUT IN THE EXPERIMENTAL OR INDUCTIVE LOGIC.

SECTION I.

Mistakes of the Ancients concerning the proper objects of Philosophy. Ideas of Bacon on the same subject.--Inductive Reasoning. Analysis and Synthesis.-Essential difference between Legitimate and Hypothetical Theories.

I HAVE had occasion to observe more than once, in the course of the foregoing speculations, that the object of physical science is not to trace necessary connexions, but to ascertain constant conjunctions; not to investigate the nature of those efficient causes on which the phenomena of the universe ultimately depend, but to examine with accuracy what the phenomena are, and what the general laws by which they are regulated.

In order to save repetitions, I here beg leave to refer to some observations on this subject in the First Part. I request more particularly the reader's attention to what I have said in the second section of the first chapter, on the distinction between physical and efficient causes; and on the origin of that bias of the imagination

which leads us to confound them under one common name. That when we see two events constantly conjoined as antecedent and consequent, our natural apprehensions dispose us to associate the idea of causation or efficiency with the former, and to ascribe to it that power or energy by which the change was produced, is a fact obvious and unquestionable; and hence it is, that in all languages, the series of physical causes and effects is metaphorically likened to a chain, the links of which are supposed to be indissolubly and necessarily connected. The slighest reflection, at the same time. must satisfy us that these apprehensions are inconsistent, and even absurd; our knowledge of physical events reaching no farther than to the laws which regulate their succession; and the words power and energy expressing attributes not of matter but of mind. It is by a natural bias or association somewhat similar (as I have remarked in the section above-mentioned) that we connect our sensations of color, with the primary qualities of body."

This idea of the object of physical science (which may be justly regarded as the ground-work of Bacon's Novum Organon) differs essentially from that which was entertained by the ancients; according to whom "Philosophy is the science of causes." If, indeed, by causes they had meant merely the constant forerunners or antecedents of events, the definition would have coincided nearly with the statement which I have given. But it is evident, that by causes they meant such antecedents as were necessarily connected with the effects, and from a knowledge of which the effects might be foreseen and demonstrated; and it was owing to this confusion between the proper objects of physics and of metaphysics, that, neglecting the observation of facts exposed to the examination of their senses, they vainly attempted, by synthetical reasoning, to deduce, as necessary consequences from their supposed causes, the phenomena and laws of nature.-"Causa ea est," says Cicero. 66 quæ id efficit cujus est causa. Non sic causa intelligi debet, ut quod cuique antecedat, id ei causa sit; sed quod cuique efficienter antecedat.-Itaque dicebat Carneades ne Apollinem quidem posse dicere futura, nisi ea quorum causas natura ita contineret, ut ea

Were it not for this bias of the imagination to identify efficient with physical causes, the attention would be continually diverted from the necessary business of life, and the useful exercise of our faculties suspended, in a fruitless astonishment at that hidden machinery, over which nature has drawn an impenetrable veil. To prevent this inconvenient distraction of thought, a farther provision is made in that gradual and imperceptible process by which the changes in the state of the universe are, in general, accomplished. If an animal or a vegetable were brought into being before our eyes, in an instant of time,-the event would not be in itself more wonderful than their slow growth to maturity from an embryo, or from a seed. But, on the former supposition, there is no man who would not perceive and acknowledge the immediate agency of an intelligent cause; whereas, according to the actual order of things, the effect steals so insensibly on the observation, that it excites little or no curiosity, excepting in those who possess a sufficient degree of reflection to contrast the present state of the objects around them, with their first origin, and with the progressive stages of their existence.

fieri necesse esset. Causis enim efficientibus quamque rem cognitis, posse denique sciri quid futurum esset."*

From this disposition to confound efficient with physical causes, may be traced the greater part of the theories recorded in the history of philosophy. It is this which has given rise to the attempts, both in ancient and modern times, to account for all the phenomena of moving bodies by means of impulse; † (see Philosophy of the Human Mind, vol. i. chap. i. sec. 2,) and it is this also which has suggested the simpler expedient of explaining them by the agency of minds united with the particles of matter. As the communication of motion by apparent impulse, and our own power to produce motion by a volition of the mind, are two facts, of which, from our earliest infancy, we have every moment had experience; we are apt to fancy that we understand perfectly the nexus by which De Fato, 48, 49. The language of Aristotle is equally explicit. Extrabat δε οιομεθ ̓ ἕκαστον άπλως, αλλά μη τον σοφιστικόν τρόπον, τον κατα συμβέβηκος, όταν την τ' αιτίαν οιώμεθα γινώσκειν, δι ἦν το πραγμα εστιν, ότι εκείνου αιτία εστι, και μη ενδέχεται τουτ' άλλως έχειν. Sciri autem putamus unamquamque rem simpliciter, non sophistico modo, id est ex accidenti, cum putamus causam cognoscere propter quam res est, ejus rei causam esse, nec posse eam aliter se habere.-Analyt. Poster. lib. i. cap. 2.

Nothing, however, can place in so strong a light Aristotle's idea of the connexion between physical causes and effects, as the analogy which he conceived it to bear to the connexion between the links of a mathematical chain of reasoning. Nor is this mode of speaking abandoned by his modern followers. "To deny a first cause," says Dr Gillies," is to deny all causation to deny axioms is, for the same reason, to deny all demonstration."-(Vol. i. p. 108.) And in another passage: "We know a mathematical proposition, when we know the causes that make it true. In demonstration, the premises are the causes of the conclusion, and therefore prior to it. We can not, therefore, demonstrate things in a circle, supporting the premises by the conclusion; because this would be to suppose, that the one proposition could be both prior and posterior to the other."-(Ibid. p. 96.) (Can one mathematical theorem be said to be prior to another in any other sense, than in respect of the order in which they are first presented to our knowledge?)

With respect to the connexion between impulse and motion, I have the misfortune to ditler from my very learned and highly respected friend M. Prévost of Geneva; whose opinions on this point may be collected from the two following sentences. "La cause diffère du simple signe précurseur, par sa force, ou son energie productive.-L'impulsion est un phénomene si commun, soumis à des lois si bien discutées, et si universelles, que toute cause qui s'y réduit semble former une classe éminente, et meriter seule le nom d'Agent."-Essais de Philosophie, tome ii. p. 174, 175.

I have read with great attention all that M. Prévost has so ingeniously urged in vindication of the theory of his illustrious countryman Le Sage; but without experiencing that conviction which I have in general received from his reasonings. The arguments of Locke and Hume on the other side of the question appear to my judgment, the longer I reflect on them, the more irresistible; not to mention the powerful support which they derive from the subsequent speculations of Boscovich. (See Locke's Essay, b. ii. chap. 23, sec. 28, 29; and Hume's Essay on Necessary Connexion, Part I.)

In employing the word misfortune, on this occasion, I have no wish to pay an unmeaning compliment; but merely to express the painful diffidence which I always feel in my own conclusions, when they happen to be at variance with those of a writer equally distinguished by the depth and by the candor of his philosopical researches.

To this last class of theories may also be referred the explanations of physical phenomena by such causes as sympathies, antipathies, Nature's horror of a void, &c. and other phrases borrowed by analogy from the attributes of animated beings.