4 ideas
| 21461 | I tried to be unsystematic and piecemeal, but failed; my papers presuppose my other views [Lewis] |
| 9565 | Zermelo made 'set' and 'member' undefined axioms [Zermelo, by Chihara] |
| 3339 | For Zermelo's set theory the empty set is zero and the successor of each number is its unit set [Zermelo, by Blackburn] |
| 19739 | The maxim for suicide is committed to the value of life, and is thus contradictory [Kant] |