38 ideas
| 15924 | Predicative definitions are acceptable in mathematics if they distinguish objects, rather than creating them? [Zermelo, by Lavine] |
| 17608 | We take set theory as given, and retain everything valuable, while avoiding contradictions [Zermelo] |
| 17607 | Set theory investigates number, order and function, showing logical foundations for mathematics [Zermelo] |
| 10870 | ZFC: Existence, Extension, Specification, Pairing, Unions, Powers, Infinity, Choice [Zermelo, by Clegg] |
| 13012 | Zermelo published his axioms in 1908, to secure a controversial proof [Zermelo, by Maddy] |
| 17609 | Set theory can be reduced to a few definitions and seven independent axioms [Zermelo] |
| 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] |
| 17832 | Zermelo showed that the ZF axioms in 1930 were non-categorical [Zermelo, by Hallett,M] |
| 13017 | Zermelo introduced Pairing in 1930, and it seems fairly obvious [Zermelo, by Maddy] |
| 13028 | Replacement was added when some advanced theorems seemed to need it [Zermelo, by Maddy] |
| 13015 | Zermelo used Foundation to block paradox, but then decided that only Separation was needed [Zermelo, by Maddy] |
| 13020 | The Axiom of Separation requires set generation up to one step back from contradiction [Zermelo, by Maddy] |
| 13486 | Not every predicate has an extension, but Separation picks the members that satisfy a predicate [Zermelo, by Hart,WD] |
| 17626 | The antinomy of endless advance and of completion is resolved in well-ordered transfinite numbers [Zermelo] |
| 13487 | In ZF, the Burali-Forti Paradox proves that there is no set of all ordinals [Zermelo, by Hart,WD] |
| 15897 | Zermelo realised that Choice would facilitate the sort of 'counting' Cantor needed [Zermelo, by Lavine] |
| 18178 | For Zermelo the successor of n is {n} (rather than n U {n}) [Zermelo, by Maddy] |
| 13027 | Zermelo believed, and Von Neumann seemed to confirm, that numbers are sets [Zermelo, by Maddy] |
| 9627 | Different versions of set theory result in different underlying structures for numbers [Zermelo, by Brown,JR] |
| 20653 | Six reduction levels: groups, lives, cells, molecules, atoms, particles [Putnam/Oppenheim, by Watson] |
| 17613 | We should judge principles by the science, not science by some fixed principles [Zermelo] |
| 20289 | Ethics is universalisable - it must involve an impartial and universal view of things [Singer] |
| 20286 | Following an inner voice for morality is irresponsible in a rational agent [Singer] |
| 20282 | The sanctity of a human life depends either on being of our species, or on being a person [Singer] |
| 20278 | 'Marginal utility' says something is more useful if it is in short supply [Singer] |
| 20281 | Why should I do anything for posterity? What has posterity ever done for me? [Singer] |
| 20276 | Conflict of rules might be avoided by greater complexity, or by a hierarchy of rules [Singer] |
| 20290 | Psychopaths may just be bored, because they cannot participate in normal emotional life [Singer] |
| 20288 | You can't condemn violent revolution without assessing the evils it prevents [Singer] |
| 21997 | In Marxism the state will be superseded [Singer] |
| 20287 | If 49% of the population can be wrong, so can 51% [Singer] |
| 21993 | Materialist history says we are subject to incomprehensible forces [Singer] |
| 20277 | Equality of interests is a minimal principle, not implying equal treatment [Singer] |
| 20279 | Equality of opportunity unfairly rewards those lucky enough to have great ability [Singer] |
| 20285 | If a right entails having the relevant desire, many creatures might have no right to life [Singer] |
| 20284 | Why should a potential person have the rights of an actual person? [Singer] |
| 20283 | Killing a chimp is worse than killing a human too defective to be a person [Singer] |