22 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] |
12056 | An ancestral relation is either direct or transitively indirect [Wiggins] |
12050 | Substances contain a source of change or principle of activity [Wiggins] |
12052 | We never single out just 'this', but always 'this something-or-other' [Wiggins] |
12055 | Sortal predications are answers to the question 'what is x?' [Wiggins] |
12059 | A river may change constantly, but not in respect of being a river [Wiggins] |
12063 | Sortal classification becomes science, with cross reference clarifying individuals [Wiggins] |
12051 | If the kinds are divided realistically, they fall into substances [Wiggins] |
12053 | 'Human being' is a better answer to 'what is it?' than 'poet', as the latter comes in degrees [Wiggins] |
12054 | Secondary substances correctly divide primary substances by activity-principles and relations [Wiggins] |
12047 | We refer to persisting substances, in perception and in thought, and they aid understanding [Wiggins] |
12057 | Matter underlies things, composes things, and brings them to be [Wiggins] |
14975 | A de dicto necessity is true in all worlds, but not necessarily of the same thing in each world [Cresswell] |
12064 | The category of substance is more important for epistemology than for ontology [Wiggins] |
12049 | Naming the secondary substance provides a mass of general information [Wiggins] |
12065 | Seeing a group of soldiers as an army is irresistible, in ontology and explanation [Wiggins] |
4375 | Evaluations are not disguised emotions; instead, emotion is a type of evaluation [Achtenberg] |