4 ideas
7791 | The simplest of the logics based on possible worlds is Lewis's S5 [Lewis,CI, by Girle] |
16157 | Insurance on the original ship would hardly be paid out if the plank version was wrecked! [Frede,M] |
11002 | Equating necessity with informal provability is the S4 conception of necessity [Lewis,CI, by Read] |
5960 | When the soul is intelligent and harmonious, it is part of god and derives from god [Plutarch] |