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A NOTE ON THE CUT-ELIMINATION PROOF IN “TRUTH WITHOUT CONTRA(DI)CTION”

Published online by Cambridge University Press:  09 October 2019

ANDREAS FJELLSTAD*
Affiliation:
Department of Philosophy, University of Bergen
*
*DEPARTMENT OF PHILOSOPHY UNIVERSITY OF BERGEN PO BOX 7805, 5020 BERGEN NORWAY E-mail: [email protected]

Abstract

This note shows that the permutation instructions presented by Zardini (2011) for eliminating cuts on universally quantified formulas in the sequent calculus for the noncontractive theory of truth IKTω are inadequate. To that purpose the note presents a derivation in the sequent calculus for IKTω ending with an application of cut on a universally quantified formula which the permutation instructions cannot deal with. The counterexample is of the kind that leaves open the question whether cut can be shown to be eliminable in the sequent calculus for IKTω with an alternative strategy.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 2019 

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References

BIBLIOGRAPHY

Da Ré, B. & Rosenblatt, L. (2018). Contraction, infinitary quantifiers, and omega paradoxes. Journal of Philosophical Logic, 47 (4), 611629.10.1007/s10992-017-9441-2CrossRefGoogle Scholar
Fjellstad, A. (2018). Infinitary contraction-free revenge. Thought: A Journal of Philosophy, 7(3), 179189.Google Scholar
Gentzen, G. (1934). Untersuchungen über das logische Schliessen i, ii. Mathematische Zeitschrift, 39, 176210, 405–431.10.1007/BF01201353CrossRefGoogle Scholar
Petersen, U. (2000). Logic without contraction as based on inclusion and unrestricted abstraction. Studia Logica, 64(3), 365403.10.1023/A:1005293713265CrossRefGoogle Scholar
Zardini, E. (2011). Truth without contra(di)ction. Review of Symbolic Logic, 4(4), 498535.10.1017/S1755020311000177CrossRefGoogle Scholar