21 ideas
18806 | Frege thought traditional categories had psychological and linguistic impurities [Frege, by Rumfitt] |
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] |
8490 | First-level functions have objects as arguments; second-level functions take functions as arguments [Frege] |
8492 | Relations are functions with two arguments [Frege] |
8487 | Arithmetic is a development of logic, so arithmetical symbolism must expand into logical symbolism [Frege] |
18899 | Frege takes the existence of horses to be part of their concept [Frege, by Sommers] |
4028 | Frege allows either too few properties (as extensions) or too many (as predicates) [Mellor/Oliver on Frege] |
8489 | The concept 'object' is too simple for analysis; unlike a function, it is an expression with no empty place [Frege] |
9947 | Concepts are the ontological counterparts of predicative expressions [Frege, by George/Velleman] |
10319 | An assertion about the concept 'horse' must indirectly speak of an object [Frege, by Hale] |
8488 | A concept is a function whose value is always a truth-value [Frege] |
9948 | Unlike objects, concepts are inherently incomplete [Frege, by George/Velleman] |
4972 | I may regard a thought about Phosphorus as true, and the same thought about Hesperus as false [Frege] |
3236 | Equality of opportunity without equality of respect would create a very inhuman society [Williams,B] |
3233 | Equality implies that people are alike in potential as well as in needs [Williams,B] |
3234 | Equality seems to require that each person be acknowledged as having a significant point of view [Williams,B] |
3235 | It is a mark of extreme exploitation that the sufferers do not realise their plight [Williams,B] |
8491 | The Ontological Argument fallaciously treats existence as a first-level concept [Frege] |