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Translations from natural deduction to sequent calculus

✍ Scribed by Jan von Plato


Publisher
John Wiley and Sons
Year
2003
Tongue
English
Weight
96 KB
Volume
49
Category
Article
ISSN
0044-3050

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✦ Synopsis


Abstract

Gentzen's “Untersuchungen” [1] gave a translation from natural deduction to sequent calculus with the property that normal derivations may translate into derivations with cuts. Prawitz in [8] gave a translation that instead produced cut‐free derivations. It is shown that by writing all elimination rules in the manner of disjunction elimination, with an arbitrary consequence, an isomorphic translation between normal derivations and cut‐free derivations is achieved. The standard elimination rules do not permit a full normal form, which explains the cuts in Gentzen's translation. Likewise, it is shown that Prawitz' translation contains an implicit process of cut elimination.