12 ideas
| 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] |
| 9195 | Intuitionists reject excluded middle, not for a third value, but for possibility of proof [Dummett] |
| 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] |
| 13128 | 'Ultimate sortals' cannot explain ontological categories [Westerhoff on Wiggins] |
| 23169 | Democratic institutions become impossible in a fanatical democracy [Russell] |
| 23170 | Liberal opinions are tentative rather than dogmatic, and are always responsive to new evidence [Russell] |
| 23171 | Empiricism is ethically superior, because dogmatism favours persecution and hatred [Russell] |
| 23172 | Empiricist Liberalism is the only view for someone who favours scientific evidence and happiness [Russell] |