Aristotle defined syllogism as, "a discourse in which, certain things having been supposed, something different from the things' supposed results of necessity because these things are so."
A propositional calculus or logic (also a sentential calculus) is a formal system in which formulae representing propositions can be formed by combining atomic propositions using logical connectives, and a system of formal proof rules allows certain formulae to be established as "theorems."
A generic term for symbolic formal systems with formulas containing quantifiable variables.
Deals with the application of logic to mathematics as well as the application of mathematics to logical analysis.
A formal system of logic that deals with the three modalities of possibility, probability, and necessity.
A term used to describe logic before the invention of mathematical logic.
A type of logic that deals with multiple values. Derived from fuzzy set theory, it deals with approximate rather than exact reasoning.