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It may

chievously false Conclusion, does not at once
become harmless, and too insignificant to be
worth refuting, as soon as that conclusion is
given up, and the false Principle is no longer
employed for that particular use.
equally well lead to some other no less mis-
chievous result. “A false premiss, according
as it is combined with this, or with that, true
one, will lead to two different false conclu-
sions. Thus, if the principle be admitted,
that any important religious errors ought to
be forcibly suppressed, this may lead either
to persecution on the one side, or to latitudi-
narian indifference on the other. Some may
be led to justify the suppression of heresies by
the civil sword; and others, whose feelings
revolt at such a procedure, and who see per-
secution reprobated and discountenanced by
those around them, may be led by the same
principle to regard religious errors as of little
or no importance, and all religious persuasions
as equally acceptable in the sight of God.” *

Thus much, as to the extensive practical influence of Fallacies, and the consequent high importance of detecting and exposing them.

Difficulty of detecting Fallacies.

$ 6. 2dly. The second remark is, that while sound reasoning is ever the more readily

* The Errors of Romanism, Ch. v. § 2. p. 228.

admitted, the more clearly it is perceived to be such, Fallacy, on the contrary, being rejected as soon as perceived, will, of course, be the more likely to obtain reception, the more it is obscured and disguised by obliquity and complexity of expression: it is thus that it is the most likely either to slip accidentally from the careless reasoner, or to be brought forward deliberately by the Sophist. Not that he ever wishes this obscurity and complexity to be perceived; on the contrary, it is for his purpose that the expression should appear as clear and simple as possible, while in reality it is the most tangled net he can contrive. Thus, whereas it is usual to express our reasoning, elliptically, so that a Premiss (or even two or three entire steps in a course of argument) which may be readily supplied, as being perfectly obvious, shall be left to be understood, the Sophist in like manner suppresses what is not obvious, but is in reality the weakest part of the argument: and uses every other contrivance to withdraw our attention (his art closely resembling the juggler's) from the quarter where the Fallacy lies. Hence the uncertainty before mentioned, to which class any individual Fallacy is to be referred : and hence it is that the difficulty of detecting and exposing Fallacy, is so much greater than that of comprehending and developing a process of

sound argument. It is like the detection and apprehension of a criminal in spite of all his arts of concealment and disguise; when this is accomplished, and he is brought to trial with all the evidence of his guilt produced, his conviction and punishment are easy; and this is precisely the case with those Fallacies which are given as examples in Logical treatises; they are in fact already detected, by being stated in a plain and regular form, and are, as it were, only brought up to receive sentence. Or again, fallacious reasoning may be compared to a perplexed and entangled mass of accounts, which it requires much sagacity and close attention to clear up, and display in a regular and intelligible form; though when this is once accomplished, the whole appears so perfectly simple, that the unthinking are apt to undervalue the skill and pains which have been employed upon it.

Moreover, it should be remembered that a very long discussion is one of the most effectual veils of Fallacy. Sophistry, like poison, is at once detected, and nauseated, when presented to us in a concentrated form ; but a Fallacy which when stated barely, in a few sentences, would not deceive a child, may deceive half the world, if diluted in a quarto volume. For, as in a calculation, one single figure incorrectly stated will enable us to


arrive at any result whatever, though every other figure, and the whole of the operations, be correct, so, a single false assumption in any process of reasoning, though every other be true, will enable us to draw what conclusion we please ; and the greater the number of true assumptions, the more likely it is that the false one will pass unnoticed.* But when you single out one step in the course of the reasoning, and exhibit it as a Syllogism with one Premiss true and the other false, the sophistry is easily perceived. To use another illustration, it is true in a course of argument, as in Mechanics, that “ nothing is stronger than its weakest part;" and consequently a

* I have seen a long argument to prove that the potato is not a cheap article of food ; in which there was an elaborate, and perhaps correct, calculation of the produce per acre of potatoes, and of wheat,- the quantity lost in branexpense of grinding, dressing, 8c. and an assumption slipped in, as it were incidentally, that a given quantity of potatoes contains but one-tenth part of nutritive matter equal to bread: from all which (and there is probably but one groundless assertion in the whole) a most triumphant result was deduced. This, however, gained the undoubting assent of a Review by no means friendly to the author, and usually noted more for scepticism than for ready assent ! “ All things,” says an apocryphal writer, “ are double, one against another, and nothing is made in vain :" unblushing assertors of falsehood seem to have a race of easy believers provided on purpose for their use : men who will not indeed believe the best-established truths of religion, but are ready to believe any thing else.

chain which has one faulty link will break : but though the number of the sound links adds nothing to the strength of the chain, it adds much to the chance of the faulty one's escaping observation.

To speak, therefore, of all the Fallacies that have ever been enumerated as too glaring and obvious to need even being mentioned, because the simple instances given in logical treatises, and there stated in the plainest and consequently most easily detected form, are such as would (in that form) deceive no one;—this, surely, shows extreme weakness, or else unfairness. It may readily be allowed, indeed, that to detect individual Fallacies, and bring them under the general rules, is a harder task than to lay down those general rules; but this does not prove that the latter office is trifling or useless, or that it does not essentially conduce to the performance of the other : there may be more ingenuity shown in detecting and arresting a malefactor, and convicting him of the fact, than in laying down a law for the trial and punishment of such persons; but the latter office, i.e. that of a legislator, is surely neither unnecessary nor trifling.

It should be added that a close observation and Logical analysis of Fallacious arguments, as it tends (according to what has been already

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