Timeline for Kunen's use of Countable Transitive Models
Current License: CC BY-SA 2.5
4 events
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| Oct 17 at 2:19 | comment | added | plm | Hi Stefan, I take issue with your claim that « Con$(ZFC)$ is merely an arithmetical statement ». It is a statement about proofs, which are in textbooks and usually defined as objects in set theory - certain sequences of formulas. It is also customary to "arithmetize" all that, but if the term "arithmetize" is used it is because a priori formulas/proofs are not arithmetical objects and statements about them are not arithmetical statements. Thus i would say that Con$(ZFC)$ is a metatheory statement, either taken as axiom or provable in the base metatheory depending on its consistency strength. | |
| Mar 3, 2011 at 19:26 | comment | added | David Fernandez-Breton | Ok., I'm starting to get the point... but I still can't imagine a model $M$ which thinks it satisfies the Foundation axiom but which is not wellfounded from the outside... I'll keep thinking about it. | |
| Mar 3, 2011 at 11:20 | history | edited | Stefan Hoffelner | CC BY-SA 2.5 |
added 365 characters in body
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| Mar 3, 2011 at 11:08 | history | answered | Stefan Hoffelner | CC BY-SA 2.5 |