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arXiv · 2610.31040

Set-theoretic inevitability

Chris Scambler·Cesare Straffelini
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Abstract

After defining the concept of inevitability for statements with the modal logic of forcing, we raise the question of which statements are inevitable under $\mathsf{ZFC}$ and under large cardinal hypotheses. We show that $\mathsf{SOA}$ (defined as $\mathsf{ZFC}^-$ + $\mathsf V=\mathsf{HC}$) plus the $\boldsymbolΣ^1_2$-perfect set property is $\mathsf{ZFC}$-inevitable, and that Projective Determinacy is inevitable in the theory of $\mathsf{ZFC}$ with a proper class of Woodin cardinals. We then discuss the possible conceptual significance of these results for the foundations of set theory.

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Chris Scambler, Cesare Straffelini. 2026-10-22. Set-theoretic inevitability. https://arxiv.org/abs/2610.31040

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