5 ideas
7791 | The simplest of the logics based on possible worlds is Lewis's S5 [Lewis,CI, by Girle] |
9987 | An aggregate in which order does not matter I call a 'set' [Bolzano] |
10856 | A truly infinite quantity does not need to be a variable [Bolzano] |
11002 | Equating necessity with informal provability is the S4 conception of necessity [Lewis,CI, by Read] |
5994 | Is the cosmos open or closed, mechanical or teleological, alive or inanimate, and created or eternal? [Robinson,TM, by PG] |