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

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

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