{ "id": "1902.07404", "version": "v1", "published": "2019-02-20T04:56:14.000Z", "updated": "2019-02-20T04:56:14.000Z", "title": "The Provability of Consistency", "authors": [ "Sergei Artemov" ], "categories": [ "math.LO" ], "abstract": "Provability semantics suggests well-principled notions of constructive truth and constructive falsity of classical sentences in Peano arithmetic PA. F is constructively true iff PA proves F. F is constructively false iff PA proves that for each x, there is a proof that x is not a proof of F. We also consider an associated notion of constructive consistency of PA, CCon(PA), for each x, there is a proof that x is not a proof of 0=1. We show that PA proves CCon(PA) hence there is no a Goedel-style impossibility barrier for case-by-case consistency proofs. Furthermore, we prove a finitary version of constructive consistency directly, for any PA-derivation S we find a finitary proof that S does not contain 0=1. This proves consistency of PA by finitary means and appears to vindicate Hilbert program of establishing consistency of formal theories.", "revisions": [ { "version": "v1", "updated": "2019-02-20T04:56:14.000Z" } ], "analyses": { "subjects": [ "03F03", "03F25", "03F30", "03F40", "03F50" ], "keywords": [ "vindicate hilbert program", "peano arithmetic pa", "case-by-case consistency proofs", "goedel-style impossibility barrier", "constructive consistency" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }