11 ideas
14970 | Normal system K has five axioms and rules [Cresswell] |
14971 | D is valid on every serial frame, but not where there are dead ends [Cresswell] |
14972 | S4 has 14 modalities, and always reduces to a maximum of three modal operators [Cresswell] |
14973 | In S5 all the long complex modalities reduce to just three, and their negations [Cresswell] |
14976 | Reject the Barcan if quantifiers are confined to worlds, and different things exist in other worlds [Cresswell] |
21563 | The 'no classes' theory says the propositions just refer to the members [Russell] |
21565 | Richard's puzzle uses the notion of 'definition' - but that cannot be defined [Russell] |
21564 | Vicious Circle: what involves ALL must not be one of those ALL [Russell] |
18198 | Mathematics is part of science; transfinite mathematics I take as mostly uninterpreted [Quine] |
14974 | A relation is 'Euclidean' if aRb and aRc imply bRc [Cresswell] |
14975 | A de dicto necessity is true in all worlds, but not necessarily of the same thing in each world [Cresswell] |