14 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] |
| 304 | Beautiful things must be different from beauty itself, but beauty itself must be present in each of them [Plato] |
| 14975 | A de dicto necessity is true in all worlds, but not necessarily of the same thing in each world [Cresswell] |
| 16120 | Knowing how to achieve immortality is pointless without the knowledge how to use immortality [Plato] |
| 303 | Say how many teeth the other has, then count them. If you are right, we will trust your other claims [Plato] |
| 302 | What knowledge is required to live well? [Plato] |
| 301 | Only knowledge of some sort is good [Plato] |
| 305 | Something which lies midway between two evils is better than either of them [Plato] |
| 7903 | The six perfections are giving, morality, patience, vigour, meditation, and wisdom [Nagarjuna] |