ANTITHESIS (ἀντίθεσις). — Opposition in meaning between two concepts or judgments. The terminology is from Aristotle, in whom *a.* has a generic scope, including under it both contradictory and contrary opposition (cf. *De Interpretatione*, ch. 7, 17 b 16; ibid., ch. 6, 17 a 33). In Kant it has assumed a more concrete meaning, denoting a proposition contradictorily opposed to the thesis, and of equal poetic value, whence the origin of the antinomies of pure reason (cf. *Critique of Pure Reason*, Bari 1940, part 2, p. 344 ff.). In Fichte, Hegel, and in general in idealism, it is the second dialectical moment of the Spirit (10, Idea), by which the negation or contradictory opposition is posited, to be resolved and surpassed in the synthesis.
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