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] |
| 21733 | The right-wing conception of freedom is based on the idea of self-ownership [Cohen,GA] |
| 21739 | Plenty of people have self-ownership, but still lack autonomy [Cohen,GA] |
| 21736 | It is doubtful whether any private property was originally acquired legitimately [Cohen,GA] |
| 21734 | It is plausible that no one has an initial right to own land and natural resources [Cohen,GA] |
| 21735 | Every thing which is now private started out as unowned [Cohen,GA] |
| 5994 | Is the cosmos open or closed, mechanical or teleological, alive or inanimate, and created or eternal? [Robinson,TM, by PG] |