See also: List of logicians.
A System of Logic --A priori and a posteriori --Abacus logic --Abduction (logic) --Abductive validation --Academia Analitica --Accuracy and precision --Ad captandum --Ad hoc hypothesis --Ad hominem --Affine logic --Affirming the antecedent --Affirming the consequent --Algebraic logic --Ambiguity --Analysis --Analysis (journal) --Analytic reasoning --Analytic–synthetic distinction --Anangeon --Anecdotal evidence --Antecedent (logic) --Antepredicament --Anti-psychologism --Antinomy --Apophasis --Appeal to probability --Appeal to ridicule --Archive for Mathematical Logic --Arché --Argument --Argument by example --Argument form --Argument from authority --Argument map --Argumentation theory --Argumentum ad baculum --Argumentum e contrario --Ariadne's thread (logic) --Aristotelian logic --Aristotle --Association for Informal Logic and Critical Thinking --Association for Logic, Language and Information --Association for Symbolic Logic --Attacking Faulty Reasoning --Australasian Association for Logic --Axiom --Axiom independence --Axiom of reducibility --Axiomatic system --Axiomatization --
Backward chaining --Barcan formula --Begging the question --Begriffsschrift --Belief --Belief bias --Belief revision --Benson Mates --Bertrand Russell Society --Biconditional elimination --Biconditional introduction --Bivalence and related laws --Blue and Brown Books --Boole's syllogistic --Boolean algebra (logic) --Boolean algebra (structure) --Boolean network --
Canonical form --Canonical form (Boolean algebra) --Cartesian circle --Case-based reasoning --Categorical logic --Categories (Aristotle) --Categories (Peirce) --Category mistake --Catuṣkoṭi --Circular definition --Circular reasoning --Circular reference --Circular reporting --Circumscription (logic) --Circumscription (taxonomy) --Classical logic --Clocked logic --Cognitive bias --Cointerpretability --Colorless green ideas sleep furiously --Combinational logic --Combinatory logic --Combs method --Common knowledge (logic) --Commutativity of conjunction --Completeness (logic) --Composition of Causes --Compossibility --Comprehension (logic) --Computability logic --Concept --Conceptualism --Condensed detachment --Conditional disjunction --Conditional probability --Conditional proof --Conditional quantifier --Confirmation bias --Conflation --Confusion of the inverse --Conjunction elimination --Conjunction fallacy --Conjunction introduction --Conjunctive normal form --Connexive logic --Connotation --Consequent --Consistency --Constructive dilemma --Contra principia negantem non est disputandum --Contradiction --Contrapositive --Control logic --Conventionalism --Converse (logic) --Converse Barcan formula --Correlative-based fallacies --Counterexample --Counterfactual conditional --Counterintuitive --Cratylism --Credibility --Criteria of truth --Critical-Creative Thinking and Behavioral Research Laboratory --Critical pedagogy --Critical reading --Critical thinking --Critique of Pure Reason --Curry's paradox --Cyclic negation --
Dagfinn Føllesdal --De Interpretatione --De Morgan's laws --Decidability (logic) --Decidophobia --Decision making --Decisional balance sheet --Deductive closure --Deduction theorem --Deductive fallacy --Deductive reasoning --Default logic --Defeasible logic --Defeasible reasoning --Definable set --Definist fallacy --Definition --Definitions of logic --Degree of truth --Denying the antecedent --Denying the correlative --Deontic logic --Description --Description logic --Descriptive fallacy --Deviant logic --Dharmakirti --Diagrammatic reasoning --Dialectica --Dialectica space --Dialetheism --Dichotomy --Difference (philosophy) --Digital timing diagram --Dignāga --Dilemma --Disjunction elimination --Disjunction introduction --Disjunctive normal form --Disjunctive syllogism --Dispositional and occurrent belief --Disquotational principle --Dissoi logoi --Division of Logic, Methodology, and Philosophy of Science --Don't-care term --Donald Davidson (philosopher) --Double counting (fallacy) --Double negation --Double negative --Double negation elimination --Doxa --Drinking the Kool-Aid --
EL++ --Ecological fallacy --Effective method --Elimination rule --Emotional reasoning --Emotions in decision-making --Empty name --Encyclopedia of the Philosophical Sciences --End term --Engineered language --Entailment --Entitative graph --Enumerative definition --Epicureanism --Epilogism --Epistemic closure --Equisatisfiability --Erotetics --Eternal statement --Etymological fallacy --European Summer School in Logic, Language and Information --Evidence --Exclusive nor --Exclusive or --Existential fallacy --Existential graph --Existential quantification --Expert --Explanandum --Explanation --Explanatory power --Extension (semantics) --Extensional context --Extensional definition --
Fa (concept) --Fact --Fallacies of definition --Fallacy --Fallacy of distribution --Fallacy of four terms --Fallacy of quoting out of context --Fallacy of the four terms --False attribution --False dilemma --False equivalence --False premise --Fictionalism --Finitary relation --Finite model property --First-order logic --First-order predicate --First-order predicate calculus --First-order resolution --Fitch-style calculus --Fluidic logic --Fluidics --Formal fallacy --Formal ontology --Formal system --Formalism (philosophy) --Forward chaining --Free logic --Free variables and bound variables --Function and Concept --Fuzzy logic --
Game semantics --Ganto's Ax --Geometry of interaction --Gilles-Gaston Granger --Gongsun Long --Grammaticality --Greedy reductionism --Grundlagen der Mathematik --
HPO formalism --Halo effect --Handbook of Automated Reasoning --Hanlon's razor --Hasty generalization --Herbrandization --Hetucakra --Heyting algebra --Higher-order predicate --Higher-order thinking --Historian's fallacy --Historical fallacy --History of logic --History of the function concept --Hold come what may --Homunculus argument --Horn clause --Hume's fork --Hume's principle --Hypothetical syllogism --
Identity (philosophy) --Identity of indiscernibles --Idola fori --Idola specus --Idola theatri --Idola tribus --If-by-whiskey --Iff --Illicit major --Illicit minor --Illuminationism --Immutable truth --Imperative logic --Implicant --Inclusion (logic) --Incomplete comparison --Inconsistent comparison --Inconsistent triad --Independence-friendly logic --Indian logic --Inductive logic --Inductive logic programming --Inference --Inference procedure --Inference rule --Inferential role semantics --Infinitary logic --Infinite regress --Infinity --Informal fallacy --Informal logic --Inquiry --Inquiry (philosophy journal) --Insolubilia --Institute for Logic, Language and Computation --Intellectual responsibility --Intended interpretation --Intension --Intensional fallacy --Intensional logic --Intensional statement --Intentional Logic --Intermediate logic --Interpretability --Interpretability logic --Interpretive discussion --Introduction rule --Introduction to Mathematical Philosophy --Intuitionistic linear logic --Intuitionistic logic --Invalid proof --Inventor's paradox --Inverse (logic) --Inverse consequences --Irreducibility --Is Logic Empirical? --Isagoge --Ivor Grattan-Guinness --
Jacobus Naveros --Jayanta Bhatta --Jingle-jangle fallacies --John Corcoran (logician) --John W. Dawson, Jr --Journal of Applied Non-Classical Logics --Journal of Automated Reasoning --Journal of Logic, Language and Information --Journal of Logic and Computation --Journal of Mathematical Logic --Journal of Philosophical Logic --Journal of Symbolic Logic --Judgment (mathematical logic) --Judgmental language --Just-so story --
Karnaugh map --Kinetic logic --Knowing and the Known --Kripke semantics --Kurt Gödel Society --
Language --Language, Proof and Logic --Lateral thinking --Law of excluded middle --Law of identity --Law of non-contradiction --Law of noncontradiction --Law of thought --Laws of Form --Laws of logic --Leap of faith --Lemma (logic) --Lexical definition --Linear logic --Linguistic and Philosophical Investigations --Linguistics and Philosophy --List of fallacies --List of incomplete proofs --List of logic journals --List of paradoxes --Logic --Logic Lane --Logic Spectacles --Logic gate --Logic in China --Logic in Islamic philosophy --Logic of class --Logic of information --Logic programming --Logica Universalis --Logica nova --Logical Analysis and History of Philosophy --Logical Investigations (Husserl) --Logical Methods in Computer Science --Logical abacus --Logical argument --Logical assertion --Logical atomism --Logical biconditional --Logical conditional --Logical conjunction --Logical constant --Logical disjunction --Logical equality --Logical equivalence --Logical extreme --Logical form --Logical harmony --Logical holism --Logical NAND --Logical NOR --Logical operator --Logical quality --Logical truth --Logicism --Logico-linguistic modeling --Logos --Loosely associated statements --Łoś–Tarski preservation theorem --Ludic fallacy --Lwów–Warsaw school of logic --
Main contention --Major term --Markov's principle --Martin Gardner bibliography --Masked-man fallacy --Material conditional --Mathematical fallacy --Mathematical logic --Meaning (linguistics) --Meaning (non-linguistic) --Meaning (philosophy of language) --Meaningless statement --Megarian school --Mental model theory of reasoning --Mereology --Meta-communication --Metalanguage --Metalogic --Metamathematics --Metasyntactic variable --Metatheorem --Metavariable --Middle term --Minimal axioms for Boolean algebra --Minimal logic --Minor premise --Miscellanea Logica --Missing dollar riddle --Modal fallacy --Modal fictionalism --Modal logic --Model theory --Modus ponens --Modus tollens --Moral reasoning --Motivated reasoning --Moving the goalposts --Multigrade predicate --Multi-valued logic --Multiple-conclusion logic --Mutatis mutandis --Mutual knowledge (logic) --Mutually exclusive events --Münchhausen trilemma --
Naive set theory --Name --Narrative logic --Natural deduction --Natural kind --Natural language --Necessary and sufficient --Necessity and sufficiency --Negation --Neutrality (philosophy) --Nirvana fallacy --Nixon diamond --No true Scotsman --Nominal identity --Non-Aristotelian logic --Non-classical logic --Non-monotonic logic --Non-rigid designator --Non sequitur (logic) --Noneism --Nonfirstorderizability --Nordic Journal of Philosophical Logic --Normal form (natural deduction) --Novum Organum --Nyaya --Nyāya Sūtras --
Object of the mind --Occam's razor --On Formally Undecidable Propositions of Principia Mathematica and Related Systems --One-sided argument --Ontological commitment --Open sentence --Opinion --Opposing Viewpoints series --Ordered logic --Organon --Original proof of Gödel's completeness theorem --Osmund Lewry --Ostensive definition --Outline of logic --Overbelief --
Package-deal fallacy --Panlogism --Paraconsistent logic --Paraconsistent logics --Parade of horribles --Paradox --Pars destruens/pars construens --Pathetic fallacy --Persuasive definition --Peter Simons (academic) --Philosophia Mathematica --Philosophical logic --Philosophy of logic --Peirce's law --Plural quantification --Poisoning the well --Polarity item --Polish Logic --Polish notation --Politician's syllogism --Polychotomous key --Polylogism --Polysyllogism --Port-Royal Logic --Possible world --Post's lattice --Post disputation argument --Post hoc ergo propter hoc --Posterior Analytics --Practical syllogism --Pragmatic mapping --Pragmatic maxim --Pragmatic theory of truth --Pramāṇa --Pramāṇa-samuccaya --Precising definition --Precision questioning --Predicable --Predicate (logic) --Predicate abstraction --Predicate logic --Preferential entailment --Preintuitionism --Prescriptivity --Presentism (historical analysis) --Presupposition --Principia Mathematica --Principle of bivalence --Principle of explosion --Principle of nonvacuous contrast --Principle of sufficient reason --Principles of Mathematical Logic --Prior Analytics --Private Eye Project --Pro hominem --Probabilistic logic --Probabilistic logic network --Problem of future contingents --Problem of induction --Process of elimination --Project Reason --Proof-theoretic semantics --Proof (truth) --Proof by assertion --Proof theory --Propaganda techniques --Proposition --Propositional calculus --Propositional function --Propositional representation --Propositional variable --Prosecutor's fallacy --Provability logic --Proving too much --Prudence --Pseudophilosophy --Psychologism --Psychologist's fallacy --
Q.E.D. --Quantification --Quantization (linguistics) --Quantum logic --
Ramism --Rationality --Razor (philosophy) --Reason --Reductio ad absurdum --Reference --Reflective equilibrium --Regression fallacy --Regular modal logic --Reification (fallacy) --Relativist fallacy --Relevance --Relevance logic --Relevant logic --Remarks on the Foundations of Mathematics --Retroduction --Retrospective determinism --Revolutions in Mathematics --Rhetoric --Rigour --Rolandas Pavilionis --Round square copula --Rudolf Carnap --Rule of inference --Rvachev function --
SEE-I --Salva congruitate --Salva veritate --Satisfiability --Scholastic logic --School of Names --Science of Logic --Scientific temper --Second-order predicate --Segment addition postulate --Self-reference --Self-refuting idea --Self-verifying theories --Semantic theory of truth --Semantics --Sense and reference --Sequent --Sequent calculus --Sequential logic --Set (mathematics) --Seven Types of Ambiguity (Empson) --Sheffer stroke --Ship of Theseus --Simple non-inferential passage --Singular term --Situation --Situational analysis --Skeptic's Toolbox --Slingshot argument --Social software (social procedure) --Socratic questioning --Soku hi --Some Remarks on Logical Form --Sophism --Sophistical Refutations --Soundness --Source credibility --Source criticism --Special case --Specialization (logic) --Speculative reason --Spurious relationship --Square of opposition --State of affairs (philosophy) --Statement (logic) --Straight and Crooked Thinking --Straight face test --Straw man --Strength (mathematical logic) --Strict conditional --Strict implication --Strict logic --Structural rule --Studia Logica --Studies in Logic, Grammar and Rhetoric --Subjective logic --Substitution (logic) --Substructural logic --Sufficient condition --Sum of Logic --Sunk costs --Supertask --Supervaluationism --Supposition theory --Survivorship bias --Syllogism --Syllogistic fallacy --Symbol (formal) --Syntactic Structures --Syntax (logic) --Synthese --Systems of Logic Based on Ordinals --
T-schema --Tacit assumption --Tarski's undefinability theorem --Tautology (logic) --Temporal logic --Temporal parts --Teorema (journal) --Term (argumentation) --Term logic --Ternary logic --Testability --Tetralemma --Textual case based reasoning --The False Subtlety of the Four Syllogistic Figures --The Foundations of Arithmetic --The Geography of Thought --The Laws of Thought --The Paradoxes of the Infinite --Theorem --Theoretical definition --Theory and Decision --Theory of justification --Theory of obligationes --Third-cause fallacy --Three men make a tiger --Tolerance (in logic) --Topical logic --Topics (Aristotle) --Tractatus Logico-Philosophicus --Train of thought --Trairūpya --Transferable belief model --Transparent Intensional Logic --TregoED --Trikonic --Trilemma --Trivial objections --Trivialism --Truth --Truth-bearer --Truth condition --Truth function --Truth value --Truthiness --Truthmaker --Type (model theory) --Type theory --Type–token distinction --
Ultrafinitism --Unification (computer science) --Unifying theories in mathematics --Uniqueness quantification --Universal logic --Universal quantification --Univocity --Unspoken rule --Use–mention distinction --
Vacuous truth --Vagrant predicate --Vagueness --Validity --Valuation-based system --Van Gogh fallacy --Venn diagram --Vicious circle principle --
Warnier/Orr diagram --Well-formed formula --What the Tortoise Said to Achilles --Willard Van Orman Quine --William Kneale --Window operator --Wisdom of repugnance --Witness (mathematics) --Word sense --