11 ideas
9879 | NF has no models, but just blocks the comprehension axiom, to avoid contradictions [Quine, by Dummett] |
9390 | Logic guides thinking, but it isn't a substitute for it [Rumfitt] |
9389 | Vague membership of sets is possible if the set is defined by its concept, not its members [Rumfitt] |
15086 | Absolute necessity might be achievable either logically or metaphysically [Hale] |
8261 | Maybe not-p is logically possible, but p is metaphysically necessary, so the latter is not absolute [Hale] |
15080 | 'Relative' necessity is just a logical consequence of some statements ('strong' if they are all true) [Hale] |
15081 | A strong necessity entails a weaker one, but not conversely; possibilities go the other way [Hale] |
15082 | Metaphysical necessity says there is no possibility of falsehood [Hale] |
15085 | 'Broadly' logical necessities are derived (in a structure) entirely from the concepts [Hale] |
15088 | Logical necessities are true in virtue of the nature of all logical concepts [Hale] |
15087 | Conceptual necessities are made true by all concepts [Hale] |