14 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] |
16129 | Evans argues (falsely!) that a contradiction follows from treating objects as vague [Evans, by Lowe] |
16459 | Is it coherent that reality is vague, identities can be vague, and objects can have fuzzy boundaries? [Evans] |
16460 | Evans assumes there can be vague identity statements, and that his proof cannot be right [Evans, by Lewis] |
16457 | There clearly are vague identity statements, and Evans's argument has a false conclusion [Evans, by Lewis] |
14974 | A relation is 'Euclidean' if aRb and aRc imply bRc [Cresswell] |
14484 | If a=b is indeterminate, then a=/=b, and so there cannot be indeterminate identity [Evans, by Thomasson] |
16224 | There can't be vague identity; a and b must differ, since a, unlike b, is only vaguely the same as b [Evans, by PG] |
14975 | A de dicto necessity is true in all worlds, but not necessarily of the same thing in each world [Cresswell] |
8066 | Butler exalts conscience, but it may be horribly misleading [Anscombe on Butler] |