13 ideas
| 14249 | Boolos reinterprets second-order logic as plural logic [Boolos, by Oliver/Smiley] |
| 10830 | Second-order logic metatheory is set-theoretic, and second-order validity has set-theoretic problems [Boolos] |
| 10829 | A sentence can't be a truth of logic if it asserts the existence of certain sets [Boolos] |
| 10832 | '∀x x=x' only means 'everything is identical to itself' if the range of 'everything' is fixed [Boolos] |
| 10834 | Weak completeness: if it is valid, it is provable. Strong: it is provable from a set of sentences [Boolos] |
| 13841 | Why should compactness be definitive of logic? [Boolos, by Hacking] |
| 10833 | Many concepts can only be expressed by second-order logic [Boolos] |
| 14759 | A thing is simply a long event, linked by qualities, and spatio-temporal unity [Broad] |
| 11842 | If short-lived happenings like car crashes are 'events', why not long-lived events like Dover Cliffs? [Broad] |
| 1556 | By nature people are close to one another, but culture drives them apart [Hippias] |
| 8160 | The present and past exist, but the future does not [Broad, by Dummett] |
| 14609 | We could say present and past exist, but not future, so that each event adds to the total history [Broad] |
| 22933 | We imagine the present as a spotlight, moving across events from past to future [Broad] |