Timeline for Is strengthening Foundation in NBG sufficient to make it prove Con(ZFC)?
Current License: CC BY-SA 4.0
7 events
| when toggle format | what | by | license | comment | |
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| Mar 29 at 20:08 | comment | added | Julia Williams | @ZuhairAl-Johar Maybe I'm misreading your formula, but I don't see it. Could you sketch your argument? | |
| Mar 29 at 19:50 | comment | added | Zuhair Al-Johar | @KamerynWilliams, the foundation scheme given here would prove second order $\in$-recursion, right? So, this means this theory is equi-consistent with MK. | |
| Mar 29 at 19:40 | comment | added | Julia Williams | Right, there is a subtlety there about nonstandard models. Thanks for raising it! | |
| Mar 29 at 19:37 | vote | accept | Zuhair Al-Johar | ||
| Mar 29 at 19:21 | comment | added | Joel David Hamkins | BTW, the proof that $V_\alpha$ is a model of ZFC in your argument is a little more subtle than what you state (as I know you know because we've discussed it), since one needs to argue that the nonstandard instances of ZFC are declared true by the satisfaction class. But one can get that by instances of reflection applied with the class as parameter, just as you mention. | |
| Mar 29 at 18:37 | comment | added | Joel David Hamkins | Yes, I should have been saying induction rather than recursion in all my remarks. | |
| Mar 29 at 18:27 | history | answered | Julia Williams | CC BY-SA 4.0 |