Definition of "logic" []

• The study of the principles of reasoning, especially of the structure of propositions as distinguished from their content and of method and validity in deductive reasoning. (noun)
• A system of reasoning: Aristotle's logic. (noun)
• A mode of reasoning: By that logic, we should sell the company tomorrow. (noun)
• The formal, guiding principles of a discipline, school, or science. (noun)
• Valid reasoning: Your paper lacks the logic to prove your thesis. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "In some things it may be well that emotion is greater than logic; but emotion _in logic_ is sad to contend with, sad even to contemplate -- and such is too often the reasoning of the untrained woman."
• "That branch of logic which deals with _the advance from individual instances to general principles_, is called _inductive logic_."
• "I certainly would have never used the term "logic" - Logic doesn't apply."