18 ideas
| 9456 | Modal logic is multiple systems, shown in the variety of accessibility relations between worlds [Jacquette] |
| 15544 | If what is actual might have been impossible, we need S4 modal logic [Armstrong, by Lewis] |
| 18823 | To say there could have been people who don't exist, but deny those possible things, rejects Barcan [Stalnaker, by Rumfitt] |
| 9457 | The two main views in philosophy of logic are extensionalism and intensionalism [Jacquette] |
| 9458 | Extensionalists say that quantifiers presuppose the existence of their objects [Jacquette] |
| 9461 | Intensionalists say meaning is determined by the possession of properties [Jacquette] |
| 7024 | Properties are universals, which are always instantiated [Armstrong, by Heil] |
| 9478 | Even if all properties are categorical, they may be denoted by dispositional predicates [Armstrong, by Bird] |
| 10729 | Universals explain resemblance and causal power [Armstrong, by Oliver] |
| 4031 | It doesn't follow that because there is a predicate there must therefore exist a property [Armstrong] |
| 10024 | The type-token distinction is the universal-particular distinction [Armstrong, by Hodes] |
| 10728 | A thing's self-identity can't be a universal, since we can know it a priori [Armstrong, by Oliver] |
| 16409 | Unlike Lewis, I defend an actualist version of counterpart theory [Stalnaker] |
| 16411 | If possible worlds really differ, I can't be in more than one at a time [Stalnaker] |
| 16412 | If counterparts exist strictly in one world only, this seems to be extreme invariant essentialism [Stalnaker] |
| 9460 | Extensionalist semantics forbids reference to nonexistent objects [Jacquette] |
| 9459 | Extensionalist semantics is circular, as we must know the extension before assessing 'Fa' [Jacquette] |
| 16410 | Extensional semantics has individuals and sets; modal semantics has intensions, functions of world to extension [Stalnaker] |