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The liar paradox and fuzzy logic

Published online by Cambridge University Press:  12 March 2014

Petr Hájek
Affiliation:
Institute of Computer Science, Academy of Sciences of the Czech Republic, Pod Vodarenskou Vezi 2, 182 07 Prague 8, Czech Republic, E-mail: hajek@uivt1.uivt.cas.cz
Jeff Paris
Affiliation:
Department of Mathematics, University of Manchester, Manchester M139PL, U.K., E-mail: jeff@ma.man.ac.uk
John Shepherdson
Affiliation:
Department of Mathematics, University of Bristol, University Walk, Bristol BS8 1TW, U.K., E-mail: john.shepherdson@bristol.ac.uk

Abstract

Can one extend crisp Peano arithmetic PA by a possibly many-valued predicate Tr(x) saying “x is true” and satisfying the “dequotation schema” for all sentences φ? This problem is investigated in the frame of Łukasiewicz infinitely valued logic.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 2000

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References

REFERENCES

[1]Brouwer, L.E.J., Über Abbildungen von Mannigfaltigkeiten, Mathematische Annalen, vol. 71 (1910), pp. 97115.CrossRefGoogle Scholar
[2]Gottwald, S., Mehrwertige Logik, Akademie-Verlag, Berlin, 1988.Google Scholar
[3]Grim, P., Mar, G., and Denis, P. St., The philosophical computer, Massachusets Institute of Technology, 1998.CrossRefGoogle Scholar
[4]Hájek, P., Fuzzy logic from the logical point of view, SOFSEM'95: Theory and practice of infor-matics (Milovy, Czech Republic, 1995) (Bartošek, M., Staudek, J., and Wiedermann, J., editors), Lecture Notes in Computer Science, vol. 1012, Springer-Verlag, pp. 3149.CrossRefGoogle Scholar
[5]Hájek, P., Ten questions and one problem on fuzzy logic, Submitted.Google Scholar
[6]Hájek, P., Fuzzy logic and arithmetical hierarchy II, Studia Logica, vol. 58 (1997), pp. 129141, to appear.CrossRefGoogle Scholar
[7]Hájek, P., Metamathematics of fuzzy logic, Kluwer, 1998.CrossRefGoogle Scholar
[8]Hájek, P. and Pudlák, P., Metamathematics of first-order arithmetic, Springer-Verlag, 1993, 460 pp.CrossRefGoogle Scholar
[9]Ragaz, M., Arithmetische Klassifikation von Formelnmengen der unendlichwertigen Logik, Ph.D. thesis, ETH ZÜrich, 1981.Google Scholar
[10]Rutledge, J. D., On the definition of an infinitely-valued predicate calculus, this Journal, vol. 25 (1960), pp. 212216.Google Scholar
[11]Scarpellini, B., Die Nichtaxiomatisierbarkeit des unendlichwertigen PrÄdikatenkalkÜls von Łukasiewicz, this Journal, vol. 27 (1962), pp. 159170.Google Scholar
[12]Skolem, T. A., Mengenlehre gegründet auf einer Logik mit unendlich vielen Wahrheitswerten, Sitzngsberichte Berliner Mathematische Gesellschaft, vol. 58 (1957), pp. 4156.Google Scholar
[13]Smart, D.R., Fixed point theorems, Cambridge University Press, 1974.Google Scholar
[14]Zadeh, L.A., Liar's paradox and truth-qualification principle, ERL Memorandum M79/34, University of California, Berkeley 1979, See also (Klir Yuan, editors: Fuzzy sets, fuzzy logic and fuzzy systems, selected papers of L.A. Zadeh, World Scientific 1996, pp. 449–463.Google Scholar