24 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] |
13017 | Zermelo introduced Pairing in 1930, and it seems fairly obvious [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] |
13487 | In ZF, the Burali-Forti Paradox proves that there is no set of all ordinals [Zermelo, by Hart,WD] |
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] |
14221 | Serious essentialism says everything has essences, they're not things, and they ground necessities [Shalkowski] |
14222 | Essences are what it is to be that (kind of) thing - in fact, they are the thing's identity [Shalkowski] |
14226 | We distinguish objects by their attributes, not by their essences [Shalkowski] |
14225 | Critics say that essences are too mysterious to be known [Shalkowski] |
14223 | De dicto necessity has linguistic entities as their source, so it is a type of de re necessity [Shalkowski] |
14224 | Equilateral and equiangular aren't the same, as we have to prove their connection [Shalkowski] |
6012 | We must choose in which of the virtues we wish to excel [Panaetius] |
6013 | Panaetius said we should live according to our natural starting-points [Panaetius, by Asmis] |
6014 | Panaetius identified courage with great-mindedness, preferring civic courage to military [Panaetius, by Asmis] |
5888 | Souls are born, since they are sensitive and inherited, so they must perish [Panaetius, by Cicero] |