Other Proofs of Old Results

✍ Scribed by Henryk Kotlarski

• Book ID: 102487895
• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 375 KB
• Volume: 44
• Category: Article
• ISSN: 0044-3050
• DOI: 10.1002/malq.19980440406

✦ Synopsis

We transform the proof of the second incompleteness theorem given in [3] to a proof-theoretic version, avoiding the use of the arithmetized completeness theorem. We give also new proofs of old results: T h e Arithmetical Hierarchy Theorem and Tarski's Theorem on undefinability of truth; the proofs in which the construction of a sentence by means of diagonalization lemma is not needed.