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METHODIST QUARTERLY REVIEW.
EDITED BY GEORGE PECK, D. D.
Art. I.-A System of Logic, ratiocinative and inductive; being
a Connected View of the Principles of Evidence, and the Method of Scientific Investigation. By John STUART MIll. First American, from the London Edition. New-York: Harper & Brothers, 82 Cliff-street.
All science, all knowledge is directly relative to, and deeply rooted in, the human understanding. The celebrated inscription of the Delphic temple, Ivád geavtóv, (Know thyself,) was worthy of a god, not only as a precept of moral conduct, but also as a principle of philosophical inquiry. In reference to the former of these grand objects, however, the maxim has always been but too little practiced. Its applicability to the other is scarcely yet recognized. Of the various sciences and arts of our day, there is not one that has been based directly, or distinctly, upon that which is the centre and soul of them all—the human mind. The science of number does not tell us what number is, how our idea of it is formed, or how we came by this and the other abstract notions. The science of extension leaves us equally in the dark concerning our knowledge—its nature and origin-of this property of bodies, upon which the science is built. The sciences conversant about the action and operations of these bodies and their several modes of existence, do not begin with explaining what these laws of material objects consist in with relation to our means of apprehending them, nor how far, or if at all, we may be assured of the reality of their existence. But that description of our knowledge which has more immediately for its subject the moral and political "sciences,” (as we call them,) is still more defective in this particular, still more distant from the source of light, than even the mathematical, or the physical departments. Instead of having been grounded upon an analysis of the mental operations in the acquisition of knowledge, these sciences all begin with a set of assumptions—whether, as in some subjects, axioms and definitions, which are termed self-evident, or, as in others, loose traditional prejudices and popular impressions, which are dignified into “laws of belief,” or “principles of common sense.”
But, verily, this is no better, logically viewed, than the Indian cosmography; which, setting the elephant that props the earth on the back of a tortoise, leaves the latter unhappy wight to find footing as it may. The questions, of course, recur :-What is our evidence for these laws of belief?-How came we to know the attributes denoted by the definitions ?-Might there not be some illusion in our assurance of the axioms? For to silence all such inquiries by the word “self-evident,” is both improper and unphilosophical: improper, for, in strictness, the term evident applies but to what is made known through a medium subjective or objective; whereas, the pretension here is, that these “truths” are apprehended intuitively: it is unphilosophical, because nothing of a general nature is, in fact, ever so apprehended. All our perceptions, whether of facts or objects, are necessarily particular: all generalities, that have any real foundation, are the results of induction, and, as such, susceptible of, and subject to, analysis and evidence.
No doubt, those sciences—even the most crude of them-have always contained truths of great positive value. But they were debarred, by the notions described, from all systematic progress. They had accordingly remained for ages in a state of stagnancy. They had been under the doom of barrenness, like the vestal virgins, (to borrow a favorite simile of Lord Bacon) for want of the proper instrument and method of cultivation. This want was to be supplied by first discrediting the mysterious efficacy ascribed to fundamental principles, decomposing them into their elements, tracing them back to their sources in the human mind, and by then observing the synthetic processes of nature in their formation and deduction. Such was the grand idea of the celebrated inductive logic or method of philosophizing, the promulgation of which, opportunely, (for really he has contributed little more than the direction,) has insured the proudest, perhaps, of earthly immortalities to the philosopher just named. That this logical reform was, in fact, the essential condition and clew to any advancement of the sciences, is strikingly visible in the immediate and rapid progress of such of them as have already been brought under its rule. We have a negative example, also, in the state of political and moral doctrine, which-partly, indeed, from the greater difficulty of the application-remains still unrescued from the chaos of empiricism, and is now merely emerging from that "outer darkness" wherein astronomy, medicine, and chemistry were wrapped, in the days of alchemy, magic, and judicial astrology.
It is not to be hence supposed, that this empress of human knowledge, this "science of sciences,” (as it has been well termed by Bacon,) had remained entirely unconceived, or even uncultivated. It was dimly included in the metaphysics of the ancients. It was indicated, though but implicitly, in the philosophia prima" of Bacona circumstance, by the by, which showed him not yet quite rid himself of the “idol" worship he sapped so successfully. In its scientific character it is substantially the same as what the Scotch philosophers have followed up under the name of mental philosophy. But in the several systems, as far as it has been developed at all, it was either mystified by wild imaginations, or confused with foreign matters, or biased by philosophical theory. There had been nowhere attempted a thorough and exclusive investigation of the mode of formation, expression, and generation, of human knowledge, together with a system of rules to correspond, for its extension and application. Writers on logic seem even still to comprehend it with some difficulty, in this its proper compass and twofold quality of science and art. Most of them continue partisans either of the syllogistic or of the inductive method; as if these were things mutually exclusive. A consequence of the career, now in its subsiding oscillations, which logic has had to run, like the other systems based upon the “first principles" above alluded to: a proof that here too the fluctuations of hypothesis are not yet quite fixed into science.
A sketch of this career will best illustrate the subject and ascertain its actual condition. But what is still more pertinent to our purpose as reviewer, it will enable us to judge exactly how far Mr. Mill, in the work before us, has supplied the defects of his predecessors, and responded to the exigences of the present posture of intelligence and of science.
Aristotle, with whom logic may be said to have commenced as a system, has treated the subject chiefly in its character of art. Not that this great intellect did not comprehend its scientific importance, as is commonly supposed. That he did, there needs no further evidence than his attempt to catalogue ideas under the ten classes, well known as the Categories. Nor has he overlooked that other element of the science, the doctrine of signs or language; which is considered, with the usual acuteness, in the book entitled, On Interpretation. The error was, in the former case, to have begun with general ideas, to have founded his crude classification on the popular notions respecting external objects and their supposed virtues and relations, instead of taking for its basis the facts of the mind and its processes : the error in respect of signs, or words, was no more than consistent, in giving us arbitrary, instead of analytical, definition.
Quite consonant, too, with his theory of these preliminaries, was the method of ratiocination which they had been prepared to subserve; a system so elaborately ingenious, so prodigiously coherent and complete, for a "first concoction,” as to have prevailed throughout the civilized world as the perfection of logic, both science and art, during twenty centuries, and to retain even to this day some respectable adherents to the full latitude of these pretensionspretensions, however, disclaimed by Aristotle's own express declarations. In fact, the syllogism has never been assailed with much success, unless by the mode of argument employed by Diogenes against the sophist who denied motion : that is, it has been supplanted rather than refuted, vanquished, but not subdued. The secret of its strength lay in the weakness of its adversaries, who sought a refutation everywhere, save where alone it was to be found, -in the analysis of the faculties and operations of the mind. Admit the "general ideas” of the Categories, admit the theory of “universal essences,” (subsequently known as the doctrine of Realism,) and the syllogism is impregnable, and must be regarded not only as a legitimate mode of reasoning, but, in the language of Whately, as the type of all reasoning whatever. But take it by the base, question its fundamental assumptions; there resides the error, and there, moreover, it is utterly impotent for its own defense.
This is what was done by Bacon, who, appearing in the fullness of time, proclaimed, that these pretended “first principles” were themselves to be examined, to be elementized; that nature was to be investigated through the medium of particular facts, and the principles deduced from them; that the actual knowledges were incapable of augmenting “human power," and the prevailing logic utterly impotent for the advancement of science. The facts, however, which he designated for elementary study, were the phenomena of matter rather than those of mind. His logical reform, as we have already intimated, consisted more in the inverse direction given to the inquiry, than in the “New Organ," which he provided for its conduct. In fact, this celebrated system, so much lauded and so little known, contains, as left by the author, but three of the six rules, or methods, of investigation now to be found in the book