@ElliotGlazer: Wtf CIC + LEM proves Con(ZF) ?!? Which then gives a proof of Con(ZF) in axiom-free Lean + LEM. Found by Mario Carneiro …
Summary
Mario Carneiro discovered that CIC plus LEM proves the consistency of ZF set theory, enabling a proof in axiom-free Lean with LEM, advancing type theoretic metamathematics.
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Cached at: 09/21/26, 03:39 PM
Wtf CIC + LEM proves Con(ZF) ?!? Which then gives a proof of Con(ZF) in axiom-free Lean + LEM. Found by Mario Carneiro with Fable. Finally some progress on the big questions in type theoretic metamathematics… https://t.co/gQ7psFnk90
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