A Logic of Facts; Or, Every-day Reasoning. George Jacob Holyoake
It is a humiliating reflection that mankind never reasoned so ill as when they most professed to cultivate the art of reasoning.—Life of Galileo, p. 1. society for the Diffusion of Useful Knowledge.
Common sense—the foundation of logic—first received (to a limited extent) the regularity of an art and the certainty of a science, from the master hand of Aristotle. Impartial scholars, familiar with his writings on logic, allow them to have not only ingenuity but real merit; and his admirers contend that he has been misunderstood by some and abused by others. This is highly probable, as we are certain that when his works were interpreted by the schools, and his logic proclaimed the great text-book of knowledge and the only weapon of truth, 'men's minds, instead of studying nature, were in an endless ferment about occult qualities and imaginary essences; little was talked of but intention and remission, proportion and degree, infinity, formality, quiddity and individuality.'* Logic then was jargon, controversy chicane, and truth a shuttlecock, with which the disputants respectively played, or the object which they mutually disguised. Logic was a labyrinth in which the subtlest lost their Way—a bourne from which the traveller after truth seldom returned.
* Account of Lord Bacon's Novum Organon Scientiarum, Lib. of
Useful Knowledge, p. 4.
A striking illustration of this has been furnished by a candid and distinguished writer—Dr. Reid. 'Of the analytics and of the topics of Aristotle, ingenuousness requires me to confess, that though I have often purposed to read the whole with care, and to understand what is intelligible, yet my courage and patience always failed me before I had done. Why should I throw away so much time and painful attention upon a thing of so little real use? If I had lived in those ages when the knowledge of Aristotle's Organon entitled a man to the highest rank in philosophy, ambition might have Induced me to employ upon it some years of painful study; and, less, I conceive, would not be sufficient. Such reflections as these always got the better of my resolution.'*
Dr. Whately, who has for many years occupied the throne of Logic and whose work maybe taken, from its currency in our colleges and academies, as the representative of the logic of the schools, seems to obviate all objections to the abstruseness of this subject by a counter charge, to the effect that logic is now underrated only because it has been overrated. But it is not the complexity found in it, but the laudations bestowed upon it which have brought it into neglect. Dr. Whately contends that certain writers, 'by representing logic as furnishing the sole instrument for the discovery of truth in all subjects, and as teaching the use of the intellectual faculties in general, raised expectations which could not be realised, and which naturally led to a reaction—to logic being regarded as utterly futile and empty.'** Deeply deploring this kind of injury, from which many important arts have suffered, I am neither disposed to defend such a course, nor to imitate it. But I demur to the truth of this representation with regard to logic. If logic be not the 'sole instrument for the discovery of truth in all subjects,' it is certainly the principal one. Instead of charging scholastic logicians with having unduly 'raised,' it would be nearer the truth, in my opinion, to say that they have confused 'expectations' by intricate machinery and extreme elaborations.
* Lord Kamet's Sketches vol. 8, chap. S. Aristotle's
Logic.
** Dr. Whately: Elements of Logic, preface, p. vii. Second
edition.
Intricacy and minuteness of detail might be a trifling disqualification did they lead to something immediately practical. But Dr. Whately contends that logic, in the most extensive sense which the name can, with propriety, be made to bear, is that of the science, and also the art of reasonings 'Inasmuch as logic institutes an analysis of the process of the mind in reasoning, it is strictly a science, while considered in reference to the practical rules it furnishes it is an art.'* He confines the province of logic, as an art, to 'employing language properly for the purpose of reasoning,' and restricts the logician to the use of the syllogism as the sole test of argument. Mr. Augustus de Morgan thus exhibits the spirit of Whately's restriction:—
Logic has nothing to do with the truth of the facts, opinions, or presumptions, from which an inference is derived; but simply takes care that the inference shall certainly be true if the premises be true.'
It has been, and is to be, objected, that logic, thus confined, 'leaves untouched the greatest difficulties, and those which are the sources of the greatest errors in reasoning.' To this powerful objection Dr. Whately thinks it sufficient to reply, that 'no art is to be censured for not teaching more than falls within its province, and, indeed, more than can be taught by any conceivable art. Such a system of universal knowledge as should instruct us in the full meaning or meanings of every term, and the truth or falsity, certainty or uncertainty of every proposition, thus superseding all other studies, it is most unphilosophical to expect, or even to imagine. And to find fault with logic for not performing this, is as if one should object to optics for not giving sight to the blind—or complain of a reading glass for being of no service to a person who had never learnt to read.'*** This would be a most conclusive answer if confident assertion could be accepted in lieu of proof. The objection still remains to be removed. We may still demand, does it not fall within the legitimate province of logic to provide means of encountering the 'greatest difficulties' with which it is confessed logic is beset? True, there is no art can teach everything, but is that a reason why logic should teach nothing, or next to nothing, compared with what seems essentially necessary?
* Intro., p. 1.
** Klein. of Logic, Synthetical Compendium, chap. 2, part
1, sec. 9.
*** Elem. of Logic, Intro., pp. 12, 13.
Dr. Whately contends that the 'difficulties' and 'errors' in the objection adduced, are in the subject matter about which logic is employed, and not in the process of reasoning—which alone is the appropriate province of logic. But it seems to me that Dr. Whately has found it impossible to keep within the bounds of the restriction he thus endeavours to establish.
In treating upon 'apprehension,' he introduces, as indeed he was obliged to do, from the department of metaphysics, several speculations on 'generalisation' and 'abstractions,' and from ontology (the science which explains the most general conceptions respecting the phenomena of nature) he borrows the leading principles of definition. Because he thus goes so far, it is not to be contended that therefore he should have gone further; but when he found he must depart from his rule and borrow from other branches of knowledge (no matter for what end), why did he not depart from it to some purpose, and borrow from natural philosophy such rules as would have guarded the logician from the 'chief errors' into which he may fall?
Dr. Whately informs us, indeed, that logic furnishes certain syllogistic forms to which all sound arguments may be reduced, and thus establishes universal tests for the detection of fallacy—but it is to be observed that it is only such fallacy as may creep in between the premises and the conclusion of an argument. It is to this narrow and Aristotelian object that logic is restricted. 'The process of reasoning itself is alone the appropriate province of logic. This process will have been correctly conducted if it have conformed to the logical rules, which preclude the possibility of any error creeping in between the principles from which we are arguing, and the conclusions we deduce from them.'* We learn from our authority, that as arithmetic does not profess to introduce any notice of the things, whether coins, persons, or dimensions, respecting which calculations are made; neither does logic undertake 'the ascertainment of facts, or the degree of evidence of doubtful propositions.' And just as an arithmetical result will be useless if the data of the calculation be incorrect, so a logical conclusion is liable to be false if the premises are so. Neither does the logic, now under consideration, concern itself with the 'discovery of truth,' excepting so far as that may be said to be implied by the detection of error in a false inference.** Logic thus, confined to the actual process of reasoning, however important its functions there, evidently leaves us in the dark as to the value of what we reason about. For the information