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

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

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