English

"Iff" is not expressible in independence-friendly logic

Logic 2008-07-01 v1

Abstract

Ordinary first-order logic has the property that two formulas \phi and \psi have the same meaning in a structure if and only if the formula ``\phi iff \psi'' is true in the structure. We prove that independence-friendly logic does not have this property.

Keywords

Cite

@article{arxiv.0806.4785,
  title  = {"Iff" is not expressible in independence-friendly logic},
  author = {Allen L. Mann},
  journal= {arXiv preprint arXiv:0806.4785},
  year   = {2008}
}

Comments

18 pages. Submitted to the Journal of Symbolic Logic

R2 v1 2026-06-21T10:55:38.549Z