ANTINOMIA. — From the Greek ἀντινομία (ἀντί, against; νόμος, law), it is the contradiction or inconsistency of a law, which gives rise to interpretations in opposite senses; or else the real or apparent conflict between two different laws (Quintilian, VII, 7, 1; ibid., 10, 2). In its derived, and today common, sense, a. generally means contradiction, conflict, or inconsistency arising from situations, principles, or lines of reasoning that present themselves as equally legitimate (practical, social, historical a., etc.).
In Kant, a. are the contradictions into which human reason becomes entangled when it considers the contents of its ideas (which have validity only as unifying representations of experience) as possible objects of science (metaphysics). They concern in particular the cosmological idea and are formulated by Kant in the form of thesis and antithesis, both equally susceptible of proof. Kant enumerates four, which together constitute « the a. of pure reason » (cf. Kr. der V. Vernunft, Die Trans. Dial., II, chap. 2; Italian trans., Bari 1940, part 2, p. 335 ff.). Kant also admits an a. of practical reason (for the concept of the highest good, the indissoluble agreement between virtue and happiness is essential; in the natural world, however, the realization of virtue is not joined to happiness: cf. Kr. der prakt. Vernunft, part 1, II, chap. 2; Italian trans., Bari 1942, pp. 136–37); an a.
of teleological judgment, concerning mechanism and purposiveness, and finally an a. of aesthetic taste (cf. Kr. der Urtheilkraft, § 56 ff. and 69 ff.; Italian trans., Bari 1938, pp. 193 ff. and 246 ff.). V. KANT.