Category:Modal logic

• Modal logic
• Necessity of identity

A

• Accessibility relation
• Accident (philosophy)
• Actualism
• Admissible rule
• Alethic modality
• Alternating-time Temporal Logic
• Apodicticity
• Assertoric
• Autoepistemic logic

B

• Barcan formula
• Buridan formula

C

• Classical modal logic
• Conceptual necessity
• Contingency (philosophy)

D

• Deontic logic
• Doxastic logic
• Dynamic epistemic logic
• Dynamic logic (modal logic)

E

• Epistemic closure
• Epistemic modal logic
• Epistemic possibility
• Essence

F

• Fiction theory
• Finite model property
• Formal ethics
• Frege–Church ontology

G

• Gabbay's separation theorem
• General frame
• Gödel's ontological proof
• Guarded logic

H

• Hennessy–Milner logic
• Hybrid logic

I

• Imperative logic
• Impossible world
• Interior algebra
• Interpretability logic

J

• Japaridze's polymodal logic

K

• KK thesis
• Kripke semantics

L

• Löb's theorem
• Logical possibility
• Logico-linguistic modeling

M

• Meaning and Necessity
• Modal algebra
• Modal companion
• Modal depth
• Modal μ-calculus
• Modal operator
• Multimodal logic

N

• Neighborhood semantics
• Non-rigid designator
• Normal modal logic

O

• Ontic

P

• Possible world
• Predicate abstraction
• Problem of future contingents
• Provability logic

R

• Regular modal logic
• Rigid designator

S

• S5 (modal logic)
• Sahlqvist formula
• Standard translation
• Strict conditional
• Subjunctive possibility

T

• Two-dimensionalism

V

• Vivid designator

W

• Window operator