20 ideas
10163 | Propositional modal logic has been proved to be complete [Kripke, by Feferman/Feferman] |
10760 | With possible worlds, S4 and S5 are sound and complete, but S1-S3 are not even sound [Kripke, by Rossberg] |
16189 | The variable domain approach to quantified modal logic invalidates the Barcan Formula [Kripke, by Simchen] |
15132 | The Barcan formulas fail in models with varying domains [Kripke, by Williamson] |
11115 | 'All horses' either picks out the horses, or the things which are horses [Jubien] |
11116 | Being a physical object is our most fundamental category [Jubien] |
11117 | Haecceities implausibly have no qualities [Jubien] |
11119 | De re necessity is just de dicto necessity about object-essences [Jubien] |
11118 | Modal propositions transcend the concrete, but not the actual [Jubien] |
11108 | Your properties, not some other world, decide your possibilities [Jubien] |
11111 | Modal truths are facts about parts of this world, not about remote maximal entities [Jubien] |
11109 | If other worlds exist, then they are scattered parts of the actual world [Jubien] |
11106 | If all possible worlds just happened to include stars, their existence would be necessary [Jubien] |
11112 | Possible worlds just give parallel contingencies, with no explanation at all of necessity [Jubien] |
11113 | Worlds don't explain necessity; we use necessity to decide on possible worlds [Jubien] |
11105 | We have no idea how many 'possible worlds' there might be [Jubien] |
11107 | If there are no other possible worlds, do we then exist necessarily? [Jubien] |
11110 | We mustn't confuse a similar person with the same person [Jubien] |
2605 | If everything uses mentalese, ALL concepts must be innate! [Putnam] |
2606 | No machine language can express generalisations [Putnam] |