Full Idea
Kripke's modal semantics presupposes that worlds are maximal and consistent, that there is a unique actual world, and that worlds are coherent (e.g. lack contradiction, obey conjunction).
Gist of Idea
Kripke's modal semantics presupposes certain facts about possible worlds
Source
report of Saul A. Kripke (Naming and Necessity lectures [1970]) by Edward N. Zalta - Deriving Kripkean Claims with Abstract Objects
Book Reference
-: 'Nous' [-], p.4