Logic, traditional
Logic, traditional
the name given to those parts and that method of treatment of formal logic which have come down substantially unchanged from classical and medieval times. Traditional logic emphasizes the analysis of propositions into subject and predicate and the associated classification into the four forms, A, E, I, O; and it is concerned chiefly with topics immediately related to these, including opposition, immediate inference, and the syllogism (see logic, formal). Associated with traditional logic are also the three so-called laws of thought — the laws of identity (q. v.), contradiction (q. v.) — and excluded middle (q. v.) — and the doctrine that these laws are in a special sense fundamental presuppositions of reasoning, or even (by some) that all other principles of logic can be derived from them or are mere elaborations of them. Induction (q. v.) has been added in comparatively modern times (dating from Bacon’s Novum Organum) to the subject matter of traditional logic. — A. C.
A. Arnauld and others,
La Logique ou l’Art de Penser, better known as the Port-Royal Logic, 1st edn., Paris, 1662 ; reprinted, Paris, 1878; English translation by T. S. Baynes, 2nd edn., London, 1851.
F. Ueberweg,
System der Logik und Geschichte der logischen Lehren, 1st edn., Bonn, 1857; 4th edn., Bonn, 1874.
C. Prantl,
Gescbichte der Logik im Abendlande, 4 vols., Leipzig, 1855-1870; reprinted, Leipzig, 1927.
H. W. B. Joseph,
An Introduction to Logic, 2nd edn., Oxford, 1916.
F. Enriques,
Per la Storia della Logica, Bologna, 1922 ; English translation by J. Rosenthal, New York, 1929.
H. Scholz,
Geschichte der Logik, Berlin, 1931.