33 ideas
| 18806 | Frege thought traditional categories had psychological and linguistic impurities [Frege, by Rumfitt] |
| 9193 | ZF set theory has variables which range over sets, 'equals' and 'member', and extensionality [Dummett] |
| 9194 | The main alternative to ZF is one which includes looser classes as well as sets [Dummett] |
| 21495 | Theoretical and practical politics are both concerned with the best lives for individuals [Russell] |
| 9195 | Intuitionists reject excluded middle, not for a third value, but for possibility of proof [Dummett] |
| 8490 | First-level functions have objects as arguments; second-level functions take functions as arguments [Frege] |
| 8492 | Relations are functions with two arguments [Frege] |
| 9186 | First-order logic concerns objects; second-order adds properties, kinds, relations and functions [Dummett] |
| 9187 | Logical truths and inference are characterized either syntactically or semantically [Dummett] |
| 9191 | Ordinals seem more basic than cardinals, since we count objects in sequence [Dummett] |
| 9192 | The number 4 has different positions in the naturals and the wholes, with the same structure [Dummett] |
| 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] |
| 21517 | Individuals need creativity, reverence for others, and self-respect [Russell] |
| 21523 | We would not want UK affairs to be settled by a world parliament [Russell] |
| 21522 | Democracy is inadequate without a great deal of devolution [Russell] |
| 21521 | Anarchy does not maximise liberty [Russell] |
| 21528 | Groups should be autonomous, with a neutral authority as arbitrator [Russell] |
| 21527 | On every new question the majority is always wrong at first [Russell] |
| 21526 | Unfortunately ordinary voters can't detect insincerity [Russell] |
| 21525 | When the state is the only employer, there is no refuge from the prejudices of other people [Russell] |
| 21518 | Men unite in pursuit of material things, and idealise greed as part of group loyalty [Russell] |
| 21519 | We need security and liberty, and then encouragement of creativity [Russell] |
| 21524 | The right to own land gives a legal right to a permanent income [Russell] |
| 8491 | The Ontological Argument fallaciously treats existence as a first-level concept [Frege] |
| 21520 | That our heaven is a dull place reflects the misery of excessive work in life [Russell] |