5 ideas
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] |
14288 | 'If A,B' affirms that A⊃B, and also that this wouldn't change if A were certain [Jackson, by Edgington] |
13769 | Conditionals are truth-functional, but should only be asserted when they are confident [Jackson, by Edgington] |
467 | A virtue is a combination of intelligence, strength and luck [Ion] |