ページの画像
PDF
ePub

interpretation of the moderns; and so far we think Dr. Brown is quite right. We can very well remember (having read Locke very attentively before we read Reid), how astonished we were at what at first appeared to be the perversity with which the Scotch philosopher interpreted many of the obviously metaphorical expressions of our great countryman. When we afterwards understood Reid's character better, we regarded it merely as a singular delusion; but it then appeared, and still appears to us, a most monstrous one.

The section entitled “The Train of Thought and the Mental • Faculties,' is for the most part truly excellent. In this he gives a brief, but very clear account of the controversy respecting the nature of general terms. We are rejoiced to see that he exposes what has always appeared to us the singularly superficial reasoniny of Stuart on this subject, and evidently coincides with the opinion of Dr. Brown, whose lectures upon it form one of the most valuable parts of his voluminous course. The monstrous absurdities of the realists had been long before exposed, but the scarcely less enormous errors of the nominalists still required detection. The following remarks are much to the purpose :

*Mr. Stuart ranks himself with the nominalists, or those who deny we can reason concerning genera without the medium of language. But this is a strange and obvious, though frequent error ; we must reason concerning genera before language is formed, and in order that language may be formed; we cannot name that which we cannot think of; classes must be formed previous to general appellations ; we must determine whether an individual belongs to the class, before we can determine whether the common name of the class can be rightly applied to it.

* The great mistake of Mr. Stuart, and the nominalists, consists in considering language as necessary to a train of thought, whereas it is thought that is necessary to language. Without thought we could have no classification ; without classification, no general terms. The modifying one single word (and this might be applied to many discussions and endless disputes) would have set every thing right. If, instead of affirming that we think solely by means of language, it had been affirmed that we think chiefly by means of language, there would have been no dissentients, and the doctrine and its inferences would have been the more correctly limited. As it is, Mr. Stuart lays far too definite a stress on language as the instrument of thought. If the doctrine of the nominalists were true, the maxim of Condillac would be true likewise, L'art de raisonner se réduit à une langue bien faite.' But though there is much truth in this, there is much more truth in the converse. If to speak well is to reason well, it is still more just, that to think right is to speak right. He, who had the most felicitous choice of words, of all writers, Horace, justly affirms, “Scribendi rectê, sapere est et principium et fons.”

pp. 260, 261.

Mr. Douglas in many parts of his book, but more especially in this section, speaks of a power or faculty which he says has been ! scarcely ever noticed by philosophers,' and to which he gives the name of the constructive faculty; or the power which the mind possesses of combining its perceptions, thoughts, and feelings; which combinations are, to the mental philosopher, the subjects of analysis. We much doubt whether there was any necessity for this new term, and still more whether it indicates any power of the mind which has not been often noticed, or involves any phenomena which are not resolvable into a combination of those principles which had already been subjected to a pretty close analysis, and received appropriate names. But as Mr. Douglas has not fully developed his views on this point, nor precisely explained the nature and limits of this faculty or power, we abstain from any further remarks. In a future edition, we hope Mr. Douglas will say more upon it.

One of the least satisfactory sections to us is that on Reasoning and Logic.' Our author still insists on the old-fashioned objections of Campbell

, Reid, and Stuart against logic (founded principally on the follies of those who exorbitantly magnified its province and its utility), without paying sufficient attention to the replies of Whately; replies founded on a more correct investigation of its nature, and on a more distinct and modest statement of its objects. It is true that Mr. Douglas has read Dr. Whately's Treatise, for he speaks of it as an admirable' one; though how a treatise can be an admirable one on a subject on which Mr. Douglas expresses himself in such terms as follows, is to us a matter of surprise. He says: • It has been doubted whether logic is an art or a science. Dr. • Whately decides that it is both. It is, indeed, as much the one as the other,-it is the science of a self-evident truism; and • the art, without understanding any subject, of disputing upon 6 all.'

We are far from being disposed to over-estimate the utility of logic, even when its objects and purposes are ever so strictly and carefully defined. Within the narrow limits, however, to which a correct investigation of its nature will ever restrict it, we believe it is of considerable value, and that so far as its proper objects are concerned, no other department of science can supply its place. We would illustrate our meaning thus :

It is quite true, as the opponents of logic contend, that by far the greater number of fallacies are owing to the ambiguities, or various and indeterminate meanings of terms.

But still there are fallacies--say one in ten, one in twenty, one in thirty, or in any other proportion, (we care not what,) which do not arise at all from the meaning of the terms, but from false inference; from haste and inaccuracy in deducing the conclusion from the premises. Now, of all such fallacies, logic, undoubtedly, gives us

an effectual test; a test which will enable us to detect logical inaccuracies, whether in our own reasonings, or in those of others. Now we contend that, if this were the sole benefit which logic conferred, it would be well worth the very moderate pains and industry necessary to secure such a knowledge of it as should be practically useful. And, by the bye, we must observe, that even in Dr. Whately's book, much, in our estimation, might have been dispensed with. The old technical system, in all its completeness, was far too cumbersome and artificial, and justified the objection that, to learn it thoroughly, would cost more time and trouble than would be repaid by any occasional benefits the knowledge would confer. Not so with a knowledge of the general structure of the syllogism; of the only valid forms of it; and of the most usual species of fallacy.

If this, then, were the only benefit as it is the only direct benefit which logic secures, we think it would be well worthy of some attention. But it is not the only one. Though it is not the proper office of any science effectually to guard us against the ambiguity or indeterminate meaning of every term, logic is indirectly, even in this respect, of considerable use; and that not merely by habituating the mind to pay particular attention to the meaning of terms, whether the fallacy be in the premises or in illogical inference from them, but still more by disclosing the source of the fallacy, which can hardly fail to appear upon the very attempt to throw the argument into the form of syllogism. Whatever the nature of the fallacy, whether it be purely in the premises or in the reasoning, it almost always arises from the abridged forms in which, in ordinary discourse and writing, we express our reasonings. Commonly one of the premises is suppressed; or the order of conclusion and premiss is frequently inverted; in that case a totally different set of particles being employed to mark the connexion. Often one of the propositions of an argument shall itself be a long conditional proposition, involving in itself an abridged syllogism, and requiring distinct analysis. The involution becomes still greater in the more complex forms of dilemma, and in that form of argument called · Sorites.' The disguises of fallacy are still further increased by the mere varieties of grammatical construction, into which the different propositions may be thrown. Sometimes the conclusion, or the premiss, may be expressed in a bold apostrophe or a startling interrogatory, prefaced with, Who can deny it?' Lastly, the premises and the conclusion are very generally separated, the interval being filled up by one or more parenthetical sentences or clauses, all tending, however, to give the fallacy an additional chance of concealment. Now it is, in such cases, that the test which logic supplies becomes principally of value; and indeed, fallacies when thus tested, become so transparent, that the

illustrations introduced into logical books, (which, by the bye, have generally been exceedingly ill-selected,) have often raised a laugh at logic as the art of discovering what every body already knows. But as fallacies meet us in books, they assume a much more formidable appearance; and the principal use of the syllogism as a test, is to enable us to detect them, and to throw them into that very form in which they are laughed at as arguments so plainly illogical, that nobody could possibly be deceived by them. Nor is it uncommon to see a somewhat muddle-headed man-who would certainly be one of the first to admit an artfully disguised fallacy—contemptuously proclaiming, when once expressed in full, the absurdiiy of supposing that any body could be deluded by it. Such conduct reminds one of Hogarth's picture of Columbus breaking the egg.

As Whately well observes, the chief danger of fallacy lies in the abridged form in which ordinary reasoning is necessarily carried on. Mr. De Morgan has also afforded some good illustrations of this point in his . First Notions of Logic preparatory to the Study of Geometry. It is in such propositions,' says he, that the greatest danger of error lies. It is also in such proposi• tions that men convey opinions which they would not willingly

express. Thus, the honest witness who said, 'I always thought • him a respectable man-he kept his gig !-would probably not

have admitted, in direct terms, · Every man who keeps a gig must be respectable.

• I shall now give a few detached illustrations of what precedes. “ His imbecility of character might have been inferred from his "proneness to favorites; for all weak princes have this failing.” • The preceding would stand very well in history, and many would 'pass it over as containing very good inference. Written, how. “ever, in the form of a syllogism, it is, 'All weak princes are prone

to favorites--he was prone to favorites; therefore, he was a weak 'prince, which is palpably wrong. The writer of such a sentence • as the preceding might have meant to say, 'For all who have this · failing are weak princes;' in which case he would have inferred ' rightly. Every one should be aware that there is much false in• ference arising out of badness of style, which is just as injurious 6 to the habits of the untrained reader, as if the errors were mis"takes of logic in the mind of the writer.'

Mr. Douglas triumphantly adduces the admissions of Whately; that Logic does not obviate difficulties in the use of language;' that it is not an engine for the investigation of nature;' that it does

not furnish a peculiar method of reasoning, &c.'- all which constituted the fallacious arguments of Campbell, Reid, and Stuart; and the supposition that they should have any weight affords, in fact, a good instance of our liability to be deceived by abridged forms of reasoning, and of the value of the syllogistic test. For

when such arguments as the above are examined, it is found that their conclusiveness rests on a suppressed premiss, which we are inclined to think few would be disposed to admit. That no science or art is useful but such as is a means of investigating nature;' that .no science or art is useful but what obviates the ambiguities and equivocations of language;' that “no science or art is useful but what furnishes us with a peculiar method of reasoning,' are propositions which, though essential to the soundness of the above arguments against logic, are propositions which would not find favor in Mr. Douglas's eyes, nor in those of any one else. Logic may be useful or not, but if useless, it is not to be proved so by showing that it does not do what lies out of its province; what it never pretends to do; what belongs to other arts and sciences, or, perhaps, to no art or science whatever ; but by distinctly showing that it does not tend to effect the specific object which it professes to effect, or that that object is a useless one. If, indeed, we were instituting a comparison between the utility of logic and that of some other art or science, such arguments as the above might find place, but not otherwise. The logic of Aristotle, even if it had been never abused, could never do for the world what the inductive philosophy of Bacon has done. But it by no means follows from this that it is useless. A spade is not so useful as a plough, but it is impossible, so far as the spade is useful, that the plough should supply its place.

As to the section on · Freedom and the Will,' though we believe we fully agree with the sentiments of Mr. Douglas, we think it is far too brief and trenchant for so important a subject; that standing on the vantage ground, which a very prolonged discussion of the subject by so many master minds has given us, he has not done sufficient justice to previous writers; that, admitting with him, as we fully do, that much needless obscurity has arisen from the terms ' necessary, necessity,' &c., and that the words

certain and certainty' would have been far better, we cannot see that the substitution of these latter terms would have made the matter so very plain and simple as he apprehends; and that if these terms were uniformly substituted, this great question would still involve a mystery which will for a long time, and perhaps for ever, (at least in this world) overshadow and perplex it. We must beg leave to explain ourselves; and we will endeavor to do it in as few sentences as possible.

We quite agree with Mr. Douglas that the very question as to the freedom of the will, is an improper one; since freedom properly belongs to action. Freedom can only mean, properly, a power of acting or not acting according to the decisions of the will; and as our author properly remarks, the question of the 'freedom of the will can only be interpreted, whether the will wills "as it wills. He also quotes with deserved approbation the words

« 前へ次へ »