Timeline for Proper classes and their consequences
Current License: CC BY-SA 2.5
4 events
| when toggle format | what | by | license | comment | |
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| Feb 19, 2011 at 15:30 | comment | added | Sergey Melikhov | The "too complicated" examples that Vopenka dealt with also exist in positive set theories, where moreover there is an operation of closure such that the closure of every class is a set. I must say that upon reading the Vopenka-Hajek book the idea of their fuzzy proper classes seemed a bit unintuitive to me, perhaps due to their only examples being non-mathematical, such as the "semiset of one's ancestors that were humans and not apes". There is no such problem with positive set theories; see my answer here: mathoverflow.net/questions/55981 | |
| Dec 5, 2010 at 5:49 | vote | accept | Avi Steiner | ||
| Dec 5, 2010 at 5:48 | vote | accept | Avi Steiner | ||
| Dec 5, 2010 at 5:49 | |||||
| Dec 4, 2010 at 22:38 | history | answered | Andreas Blass | CC BY-SA 2.5 |