deduction

deduction, in logic, form of inference such that the conclusion must be true if the premises are true. For example, if we know that all men have two legs and that John is a man, it is then logical to deduce that John has two legs. Logicians contrast deduction with induction, in which the conclusion might be false even when the premises are true. Deduction has to do with necessity; induction has to do with probability. The famous Aristotelian syllogism is one species of deductive reasoning, which was greatly extended by the development of symbolic logic.

See R. J. Ackermann, Modern Deductive Logic (1971); P. J. Hurley A Concise Introduction to Logic (1985).

Questia, a part of Gale, Cengage Learning. www.questia.com
Publication information: Article title: deduction. Encyclopedia title: The Columbia Encyclopedia, 6th ed.. © 2012 The Columbia Electronic Encyclopedia © 2012, Columbia University Press. Licensed from Columbia University Press. Used with the permission of Columbia University Press. All Rights Reserved. Publisher: The Columbia University Press. Place of publication: Not available. Publication year: 2013.

This material is protected by copyright and, with the exception of fair use, may not be further copied, distributed or transmitted in any form or by any means.