Lifting up the proof theory to the countables : Zermelo-Fraenkel set theory

Abstract

We describe the countable ordinals in terms of iterations of Mostowski collapsings. This gives a proof-theoretic bound of definable countable ordinals in the Zermelo-Fraenkel's set theory ZF.

Cited by in corpus (2)

• Intuitionistic fixed point theories over set theories
• Conservations of first-order reflections