English

Foundations with Imagination

Logic 2026-01-29 v1

Abstract

We show that countable set theory, ZFC+x xωZFC^{-}+\forall x\ |x|\leq\omega, is unable to eliminate imaginaries. In other words, this theory cannot provide representatives for arbitrary definable equivalence relations. We also see that ZFCZFC^{-} and ZFC^{-}+\exists\kappa(Inacc(\kappa)\wedge\forall x\ |x|\leq\kappa)$ also fail to eliminate imaginaries.

Cite

@article{arxiv.2601.20057,
  title  = {Foundations with Imagination},
  author = {Toby Meadows},
  journal= {arXiv preprint arXiv:2601.20057},
  year   = {2026}
}
R2 v1 2026-07-01T09:22:57.887Z