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

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

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