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_.[1] 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. [Footnote 1: According to Diogenes Laertius, v., 28, Aristotle put Rhetoric and Dialectic together, as aiming at persuasion, [Greek: to pithanon]; and Analytic and Philosophy as aiming at truth. Aristotle does, indeed, distinguish between (1) _Logic_, or Analytic, as the theory or method of arriving at true or apodeictic conclusions; and (2) _Dialectic_ as the method of arriving at conclusions that are accepted or pass current as true, [Greek: endoxa] _probabilia_; conclusions in regard to which it is not taken for granted that they are false, and also not taken for granted that they are true in themselves, since that is not the point. What is this but the art of being in the right, whether one has any reason for being so or not, in other words, the art of attaining the appearance of truth, regardless of its substance? That is, then, as I put it above. Aristotle divides all conclusions into logical and dialectical, in the manner described, and then into eristical. (3) _Eristic_ is the method by which the form of the conclusion is correct, but the premisses, the materials from which it is drawn, are not true, but only appear to be true. Finally (4) _Sophistic_ is the method in which the form of the conclusion is false, although it seems correct. These three last properly belong to the art of Controversial Dialectic, as they have no objective truth in view, but only the appearance of it, and pay no regard to truth itself; that is to say, they aim at victory. Aristotle's book on _Sophistic Conclusions_ was edited apart from the others, and at a later date. It was the last book of his _Dialectic_.]