Controversial Dialectic is the art of disputing, and of disputing in such a way as to hold one's own, whether one is in the right or the wrong - per fas et nefas. A man may be objectively in the right, and nevertheless in the eyes of bystanders, and sometimes in his own, he may come off worst. For example, I may advance a proof of some assertion, and my adversary may refute the proof, and thus appear to have refuted the assertion, for which there may, nevertheless, be other proofs. In this case, of course, my adversary and I change places: he comes off best, although, as a matter of fact, he is in the wrong.
If the reader asks how this is, I reply that it is simply the natural baseness of human nature. If human nature were not base, but thoroughly honourable, we should in every debate have no other aim than the discovery of truth; we should not in the least care whether the truth proved to be in favour of the opinion which we had begun by expressing, or of the opinion of our adversary. That we should regard as a matter of no moment, or, at any rate, of very secondary consequence; but, as things are, it is the main concern. Our innate vanity, which is particularly sensitive in reference to our intellectual powers, will not suffer us to allow that our first position was wrong and our adversary's right. The way out of this difficulty would be simply to take the trouble always to form a correct judgment. For this a man would have to think before he spoke. But, with most men, innate vanity is accompanied by loquacity and innate dishonesty. They speak before they think; and even though they may afterwards perceive that they are wrong, and that what they assert is false, they want it to seem the contrary. The interest in truth, which may be presumed to have been their only motive when they stated the proposition alleged to be true, now gives way to the interests of vanity: and so, for the sake of vanity, what is true must seem false, and what is false must seem true.
However, this very dishonesty, this persistence in a proposition which seems false even to ourselves, has something to be said for it. It often happens that we begin with the firm conviction of the truth of our statement; but our opponent's argument appears to refute it. Should we abandon our position at once, we may discover later on that we were right after all: the proof we offered was false, but nevertheless there was a proof for our statement which was true. The argument which would have been our salvation did not occur to us at the moment. Hence we make it a rule to attack a counter-argument, even though to all appearances it is true and forcible, in the belief that its truth is only superficial, and that in the course of the dispute another argument will occur to us by which we may upset it, or succeed in confirming the truth of our statement. In this way we are almost compelled to become dishonest; or, at any rate, the temptation to do so is very great. Thus it is that the weakness of our intellect and the perversity of our will lend each other mutual support; and that, generally, a disputant fights not for truth, but for his proposition, as though it were a battle pro aris et focis. He sets to work per fas et nefas; nay, as we have seen, he cannot easily do otherwise. As a rule, then, every man will insist on maintaining whatever he has said, even though for the moment he may consider it false or doubtful.
To some extent every man is armed against such a procedure by his own cunning and villainy. He learns by daily experience, and thus comes to have his own natural Dialectic, just as he has his own natural Logic. But his Dialectic is by no means as safe a guide as his Logic. It is not so easy for any one to think or draw an inference contrary to the laws of Logic; false judgments are frequent, false conclusions very rare. A man cannot easily be deficient in natural Logic, but he may very easily be deficient in natural Dialectic, which is a gift apportioned in unequal measure. In so far natural Dialectic resembles the faculty of judgment, which differs in degree with every man; while reason, strictly speaking, is the same. For it often happens that in a matter in which a man is really in the right, he is confounded or refuted by merely superficial arguments; and if he emerges victorious from a contest, he owes it very often not so much to the correctness of his judgment in stating his proposition, as to the cunning and address with which he defended it.