11 ideas
| 18261 | A simplification which is complete constitutes a definition [Kant] |
| 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] |
| 22275 | Logic gives us the necessary rules which show us how we ought to think [Kant] |
| 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] |
| 18260 | If we knew what we know, we would be astonished [Kant] |
| 19724 | Belief is knowledge if it is true, certain, and obtained by a reliable process [Ramsey] |