CIC + LEM surprisingly proves Con(ZF), a breakthrough found with AI tool Fable
leloykun · x · 2026-09-21
- Mathematician Elliot Glazer reports a surprising result: Con(ZF), the consistency of ZF set theory, can be proven in CIC (calculus of inductive constructions) plus excluded middle (LEM).
- The discovery was made by Mario Carneiro with the help of the AI tool Fable, yielding a proof of Con(ZF) in axiom-free Lean + LEM.
- He calls it rare, real progress on the big questions in type-theoretic metamathematics.
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