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] |
| 12699 | A body would be endless disunited parts, if it did not have a unifying form or soul [Leibniz] |
| 12700 | Form or soul gives unity and duration; matter gives multiplicity and change [Leibniz] |
| 12736 | If we understand God and his choices, we have a priori knowledge of contingent truths [Leibniz, by Garber] |
| 12698 | Every body contains a kind of sense and appetite, or a soul [Leibniz] |
| 1513 | The Egyptians were the first to say the soul is immortal and reincarnated [Herodotus] |