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

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

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