Dialectic, it may be added, is no novelty in philosophy. Among the ancients Plato is termed the inventor of Dialectic; and his right to the name rests on the fact, that the Platonic philosophy first gave the free scientific, and thus at the same time the objective, form to Dialectic. Socrates, as we should expect from the general character of his philosophising, has the dialectical element in a predominantly subjective shape, that of Irony. He used to turn his Dialectic, first against ordinary consciousness, and then especially against the Sophists. In his conversations he used to simulate the wish for some clearer knowledge about the subject under discussion, and after putting all sorts of questions with that intent, he drew on those with whom he conversed to the opposite of what their first impressions had pronounced correct. If, for instance, the Sophists claimed to be teachers, Socrates by a series of questions forced the Sophist Protagoras to confess that all learning is only recollection. In his more strictly scientific dialogues Plato employs the dialectical method to show the finitude of all hard and fast terms of understanding. Thus in the Parmenides he deduces the many from the one, and shows nevertheless that the many cannot but define itself as the one. In this grand style did Plato treat Dialectic. In modern times it was, more than any other, Kant who resuscitated the name of Dialectic, and restored it to its post of honour. He did it, as we have seen (§ 48), by working out the Antinomies of the reason. The problem of these Antinomies is no mere subjective piece of work oscillating between one set of grounds and another; it really serves to show that every abstract proposition of understanding, taken precisely as it is given, naturally veers round into its opposite.