Traditional or BooleanLogic treats purely binary logical states: a statement can only be either 100% true or 100% false. ---- BooleanLogic connectives are defined by truth tables where 1 is '''true''' and 0 is '''false''', i.e., For "and" symbolized as "&" or "^" or "∧" (or "&&" in CeeLanguage/CeePlusPlus/JavaLanguage, etc.) ^ | A B ---+------ 0 | 0 0 0 | 1 0 0 | 0 1 1 | 1 1 For "or" symbolized as "|" or "v" or "∨" (or "||" in the languages above) v | A B ---+------ 0 | 0 0 1 | 1 0 1 | 0 1 1 | 1 1 "Not" is "~" (or "!" or "¬") ~ | A ---+--- 1 | 0 0 | 1 and "implication" (see LogicalImplication) or "If..then.." is "->" or "⇒" (conditional) -> | A B ----+------ 1 | 0 0 0 | 1 0 1 | 0 1 1 | 1 1 "Iff" or "If and only if" is "<->" or "⇔" (biconditional) is the same as (A -> B) ^ (B -> A) There are many axioms of BooleanLogic, including DeMorgansLaws, and some deduction rule, such as A^(A->B) -> B This means, when doing proofs in logic or mathematics, in any step if A (which can be a complex expression) is true (or an assumption) and there is a definition, assumption, axiom or previously proved theorem of the form A->B, then B can be introduced into the proof chain. For more truth tables, see * http://whyslopes.com/volume1a/ch23_Truth_Tables_From_Occurence_Tables.html It should be noted that implication in BooleanLogic does not model the way the human mind does implication; it's a rather forced fit. This continues to cause theoretical and pragmatic issues that motivate a continuing search for a more suitable model. ---- See also FuzzyLogic, FirstOrderLogic, SymbolicLogic, TheoremProving, ThreeValuedLogic, TetralemmicLogic, MultiValuedLogic ---- CategoryLogic