17 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] |
18933 | Not-Being obviously doesn't exist, and the five modes of Being are all impossible [Gorgias, by Diog. Laertius] |
14974 | A relation is 'Euclidean' if aRb and aRc imply bRc [Cresswell] |
13804 | A property is essential iff the object would not exist if it lacked that property [Forbes,G] |
13805 | Properties are trivially essential if they are not grounded in a thing's specific nature [Forbes,G] |
13808 | A relation is essential to two items if it holds in every world where they exist [Forbes,G] |
13806 | Trivially essential properties are existence, self-identity, and de dicto necessities [Forbes,G] |
13807 | A property is 'extraneously essential' if it is had only because of the properties of other objects [Forbes,G] |
13809 | One might be essentialist about the original bronze from which a statue was made [Forbes,G] |
14975 | A de dicto necessity is true in all worlds, but not necessarily of the same thing in each world [Cresswell] |
13810 | The source of de dicto necessity is not concepts, but the actual properties of the thing [Forbes,G] |
9866 | Gorgias says rhetoric is the best of arts, because it enslaves without using force [Gorgias, by Plato] |
5864 | Destroy seriousness with laughter, and laughter with seriousness [Gorgias] |