12 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] |
14975 | A de dicto necessity is true in all worlds, but not necessarily of the same thing in each world [Cresswell] |
22480 | Possessing the virtue of justice disposes a person to good practical rationality [Foot] |
22477 | Calling a knife or farmer or speech or root good does not involve attitudes or feelings [Foot] |
467 | A virtue is a combination of intelligence, strength and luck [Ion] |
22478 | The essential thing is the 'needs' of plants and animals, and their operative parts [Foot] |
22479 | Observing justice is necessary to humans, like hunting to wolves or dancing to bees [Foot] |