Introductory note to 1999a
Solomon Feferman, John W Dawson, Stephen Cole Kleene, Gregory Martin Moore, Robert M Solovay, Jean van HEIJENOORT · 2001
Abstract Hahn had asked whether every independence proof for formulas of the propositional calculus could be carried out with a finite model. Gödel here presents an independence proof using an infinite model and shows that no finite model would suffice. It was less than three months after this colloquium that Gödel answered a previous query of Hahn’s about the intuitionistic propositional calculus by again showing the inadequacy of finite models; see Gödel 1992.