Proof theory – Set theory – Formal system – Predicate logic – Predicate – Higher-order logic – Propositional calculus – Proposition – Boolean algebra – Boolean logic – Truth value – Venn diagram – Pierce's law – Aristotelian logic – Non-Aristotelian logic – Informal logic – Fuzzy logic – Infinitary logic – Infinity – Categorical logic – College logic – Linear logic – Metalogic – order – Ordered logic – Temporal logic – Sequential logic – Provability logic – Interpretability logic – Interpretability – Quantum logic – Relevant logic – Consequent – Affirming the consequent – Antecedent – Denying the antecedent – Theorem – Axiom – Axiomatic system – Axiomatization – Conditional proof – Invalid proof – Degree of truth – Truth – Truth condition – Truth function – Double negative – Double negative elimination – Fallacy – Existential fallacy – Logical fallacy – Syllogistic fallacy – Type theory – Game theory – Game semantics – Rule of inference – Inference procedure – Inference rule –Quantification Introduction rule – Law of excluded middle – Law of non-contradiction – Logical constant – Logical connective – Quantifier – Logic gate – Boolean Function – Tautology – Logical assertion – Logical conditional – Logical biconditional – Logical equivalence – Logical AND – Negation – Logical OR – Logical NAND – Logical NOR – Contradiction – Logicism – Polysyllogism – Syllogism – Hypothetical syllogism – Major premise – Minor premise – Term – Singular term – Major term – Middle term – Quantification – Plural quantification – Logical argument – Validity – Soundness – Inverse (logic) – Non sequitur – Tolerance – Satisfiability – Logical language – Paradox – Polish notation – Principia Mathematica – Quod erat demonstrandum – Reductio ad absurdum – Rhetoric – Self-reference – Necessary and sufficient – Sufficient condition – Nonfirstorderizability – Occam's Razor – Socratic dialoge – Socratic method – Argument form – Logic programming – Unification –