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

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

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