nLab
S5 modal logic

The modal logic obtained from S4 modal logic by adding the axiom that there is the implication

pp. \lozenge p \to \Box \lozenge p \,.

In the Kripke frame semantics for modal logic, the accessibility relation for worlds is an equivalence relation.

References

Last revised on December 1, 2014 at 12:24:17. See the history of this page for a list of all contributions to it.