Kripke's Worlds

Possible worlds models were introduced by Saul Kripke in the early 1960s. Basically, a possible world''s model is nothing but a graph with labelled nodes and labelled edges. Such graphs provide semantics for various modal logics (alethic, temporal, epistemic and doxastic, dynamic, deontic, description logics) and also turned out useful for other nonclassical logics (intuitionistic, conditional, se...