Theory, Stable theory, Set theory, Superstring theory, Critical theory, Theory of computation, Theory X and Theory Y, Grounded theory, Computability theory, Type theory, M-theory, Theory-theory, Scientific theory, Theory (mathematical logic), String theory, Game theory, Model theory, Number theory, Twistor theory, Theory of everything, Decision theory, Gauge theory, Intuitionistic type theory, Probability theory, Naive set theory, Information theory, Negotiation theory, Economic Theory, Systems theory, Germ theory denialism, Descriptivist theory of names, Götaland theory, Group theory, Unified field theory, Communication theory, Queer theory, Nordström's theory of gravitation, Practice theory, Cannon–Bard theory, Fringe theory, Theory of relativity

Molecular orbital theory, Morse–Kelley set theory, Circumscription theory, Dynamical systems theory, Organizational theory, Scalar–tensor theory, International relations theory, Theory of mind, C-K theory, Complexity theory and organizations, Lie theory, Statistical theory, Drive theory, Labeling theory, Theory (clothing retailer), Inter-universal Teichmüller theory, BCS theory, Vapnik–Chervonenkis theory, Social theory, Strain theory (sociology), Continuity theory, Psychoanalytic theory, Cell theory, Lawvere theory, Emission theory (relativity), Combinatorial game theory, Seiberg–Witten theory, Quare theory, Coding theory, Outline of critical theory, Interpolation theory, Caloric theory, F-theory, Labor theory of value, Type II string theory, Path–goal theory, Evolution as fact and theory, Literary theory, Causal theory of reference, Germ theory of disease, Conspiracy theory, Twisted K-theory, Quantum field theory, Sociological theory, Bisexual theory, Yang–Mills theory, Heterotic string theory, Equity theory, Temporal theory (hearing), Actor–network theory

Theory, Stable theory, Set theory, Superstring theory, Critical theory, Theory of computation, Theory X and Theory Y, Grounded theory, Computability theory, Type theory, M-theory, Theory-theory, Scientific theory, Theory (mathematical logic), String theory, Game theory, Model theory, Number theory, Twistor theory, Theory of everything, Decision theory, Gauge theory, Intuitionistic type theory, Probability theory, Naive set theory, Information theory, Negotiation theory, Economic Theory, Systems theory, Germ theory denialism, Descriptivist theory of names, Götaland theory, Group theory, Unified field theory, Communication theory, Queer theory, Nordström's theory of gravitation, Practice theory, Cannon–Bard theory, Fringe theory, Theory of relativity, Molecular orbital theory, Morse–Kelley set theory, Circumscription theory, Dynamical systems theory, Organizational theory, Scalar–tensor theory, International relations theory, Theory of mind, C-K theory, Complexity theory and organizations, Lie theory, Statistical theory, Drive theory, Labeling theory, Theory (clothing retailer), Inter-universal Teichmüller theory, BCS theory, Vapnik–Chervonenkis theory, Social theory, Strain theory (sociology), Continuity theory, Psychoanalytic theory, Cell theory, Lawvere theory, Emission theory (relativity), Combinatorial game theory, Seiberg–Witten theory, Quare theory, Coding theory, Outline of critical theory, Interpolation theory, Caloric theory, F-theory, Labor theory of value, Type II string theory, Path–goal theory, Evolution as fact and theory, Literary theory, Causal theory of reference, Germ theory of disease, Conspiracy theory, Twisted K-theory, Quantum field theory, Sociological theory, Bisexual theory, Yang–Mills theory, Heterotic string theory, Equity theory, Temporal theory (hearing), Actor–network theory, Chern–Simons theory, Theory of Colours, Two-factor theory, Set theory (music), Theory of a Deadman, Zermelo set theory, Valence bond theory, Regality theory, Theory of art, Contract theory, Dual-coding theory, Matrix string theory, Miasma theory, Theory of forms, Bow-wow theory, K-theory, Postdevelopment theory, Representation theory, Control theory, Graph theory, Algorithmic learning theory, Pattern theory, Subjective theory of value, Transition state theory, Introduction to M-theory, Development theory, Singularity theory, Transformational theory, Potential theory, Liouville field theory, Dependency theory, Perturbation theory, Power transition theory, A Theory of Justice, Grand Unified Theory, Brans–Dicke theory, Ginzburg–Landau theory, Constructive set theory, Kripke–Platek set theory, Kaluza–Klein theory, Journal of Approximation Theory, Supersymmetric theory of stochastic dynamics, Ring theory, Empathising–systemising theory, Journal of Combinatorial Theory, Feminist theory, Theories of humor, ∞-Chern–Weil theory, Automata theory, Film theory, Dempster–Shafer theory, Optimality theory, Einstein–Cartan theory, Free-radical theory of aging, Structuration theory, World-systems theory, Elastica theory, Identity theory, Homotopy type theory, Normalization process theory