13 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] |
| 14974 | A relation is 'Euclidean' if aRb and aRc imply bRc [Cresswell] |
| 9295 | Not only substances have attributes; events, actions, states and qualities can have them [Teichmann] |
| 14975 | A de dicto necessity is true in all worlds, but not necessarily of the same thing in each world [Cresswell] |
| 19729 | 'Modal epistemology' demands a connection between the belief and facts in possible worlds [Black,T] |
| 19728 | Gettier and lottery cases seem to involve luck, meaning bad connection of beliefs to facts [Black,T] |
| 9293 | Body-spirit interaction ought to result in losses and increases of energy in the material world [Teichmann] |
| 9294 | No individuating marks distinguish between Souls [Teichmann] |
| 9292 | The Soul has no particular capacity (in the way thinking belongs to the mind) [Teichmann] |