13 ideas
| 7791 | The simplest of the logics based on possible worlds is Lewis's S5 [Lewis,CI, by Girle] |
| 15567 | Some events involve no change; they must, because causal histories involve unchanges [Lewis] |
| 15561 | The events that suit semantics may not be the events that suit causation [Lewis] |
| 15565 | Events have inbuilt essences, as necessary conditions for their occurrence [Lewis] |
| 15566 | Events are classes, and so there is a mereology of their parts [Lewis] |
| 15564 | An event is a property of a unique space-time region [Lewis] |
| 15563 | Properties are very abundant (unlike universals), and are used for semantics and higher-order variables [Lewis] |
| 11002 | Equating necessity with informal provability is the S4 conception of necessity [Lewis,CI, by Read] |
| 1554 | Contradiction is impossible, since only one side of the argument refers to the true facts [Prodicus, by Didymus the Blind] |
| 15562 | Causation is a general relation derived from instances of causal dependence [Lewis] |
| 1555 | People used to think anything helpful to life was a god, as the Egyptians think the Nile a god [Prodicus] |
| 535 | The gods are just personified human benefits [Prodicus] |
| 1543 | He denied the existence of the gods, saying they are just exaltations of things useful for life [Prodicus] |