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A HENKIN-STYLE PROOF OF COMPLETENESS FOR FIRST-ORDER ALGEBRAIZABLE LOGICS

Published online by Cambridge University Press:  13 March 2015

PETR CINTULA
Affiliation:
INSTITUTE OF COMPUTER SCIENCE, ACADEMY OF SCIENCES OF THE CZECH REPUBLIC, POD VODÁRENSKOU VĚŽÍ 2, 182 07 PRAGUE, CZECH REPUBLICE-mail:cintula@cs.cas.czURL:http://www.cs.cas.cz/cintula
CARLES NOGUERA
Affiliation:
INSTITUTE OF INFORMATION THEORY AND AUTOMATION, ACADEMY OF SCIENCES OF THE CZECH REPUBLIC, POD VODÁRENSKOU VĚŽÍ 4, 182 08 PRAGUE, CZECH REPUBLICE-mail:noguera@utia.cas.czURL:http://www.carlesnoguera.cat

Abstract

This paper considers Henkin’s proof of completeness of classical first-order logic and extends its scope to the realm of algebraizable logics in the sense of Blok and Pigozzi. Given a propositional logic L (for which we only need to assume that it has an algebraic semantics and a suitable disjunction) we axiomatize two natural first-order extensions L∀m and L∀ and prove that the former is complete with respect to all models over algebras from , while the latter is complete with respect to all models over relatively finitely subdirectly irreducible algebras. While the first completeness result is relatively straightforward, the second requires non-trivial modifications of Henkin’s proof by making use of the disjunction connective. As a byproduct, we also obtain a form of Skolemization provided that the algebraic semantics admits regular completions. The relatively modest assumptions on the propositional side allow for a wide generalization of previous approaches by Rasiowa, Sikorski, Hájek, Horn, and others and help to illuminate the “essentially first-order” steps in the classical Henkin’s proof.

Type
Articles
Copyright
Copyright © The Association for Symbolic Logic 2015 

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References

REFERENCES

Blok, Willem J. and Pigozzi, Don L., Algebraizable logics, Memoirs of the American Mathematical Society, vol. 396, American Mathematical Society, Providence, RI, 1989, Freely downloadable fromhttp://orion.math.iastate.edu/dpigozzi/.Google Scholar
Cintula, Petr and Noguera, Carles, A general framework for mathematical fuzzy logic, Handbook of mathematical fuzzy logic - volume 1 (Cintula, Petr, Hájek, Petr, and Noguera, Carles, editors), Studies in Logic, Mathematical Logic and Foundations, vol. 37, College Publications, London, 2011, pp. 103207.Google Scholar
Cintula, Petr and Noguera, Carles, The proof by cases property and its variants in structural consequence relations, Studia Logica, vol. 101 (2013), no. 4, pp. 713747.CrossRefGoogle Scholar
Czelakowski, James, Protoalgebraic logics, Trends in Logic, vol. 10, Kluwer, Dordrecht, 2001.CrossRefGoogle Scholar
Dummett, Michael, A propositional calculus with denumerable matrix, this Journal, vol. 24 (1959), no. 2, pp. 97106.Google Scholar
Font, Josep Maria, Jansana, Ramon, and Pigozzi, Don L., A survey of Abstract Algebraic Logic, Studia Logica, vol. 74 (2003), no. 1–2, Special Issue on Abstract Algebraic Logic II, pp. 1397.Google Scholar
Galatos, Nikolaos, Jipsen, Peter, Kowalski, Tomasz, and Ono, Hiroakira, Residuated lattices: An algebraic glimpse at substructural logics, Studies in Logic and the Foundations of Mathematics, vol. 151, Elsevier, Amsterdam, 2007.Google Scholar
Gödel, KurtÜber die Vollständigkeit des Logikkalküls, Ph.D. thesis, University of Vienna, 1929.Google Scholar
Gödel, Kurt, Die Vollständigkeit der Axiome des logischen Funktionenkalküls, Monatshefte für Mathematik und Physik, vol. 37 (1930), pp. 349360.CrossRefGoogle Scholar
Gödel, Kurt, Zur intuitionistischen Arithmetik und Zahlentheorie, Ergebnisse eines mathematischen Kolloquiums, vol. 4 (1933), pp. 3438.Google Scholar
Hájek, Petr, Metamathematics of fuzzy logic, Trends in Logic, vol. 4, Kluwer, Dordrecht, 1998.Google Scholar
Hájek, Petr and Cintula, Petr, On theories and models in fuzzy predicate logics, this Journal, vol. 71 (2006), no. 3, pp. 863–880.Google Scholar
Hájek, Petr and Montagna, Franco, A note on the first-order logic of complete BL-chains, Mathematical Logic Quarterly, vol. 54 (2008), no. 4, pp. 435446.Google Scholar
Hay, Louise Schmir, Axiomatization of the infinite-valued predicate calculus, this Journal, vol. 28 (1963), no. 1, pp. 77–86.Google Scholar
Henkin, Leon, The completeness of formal systems, Ph.D. thesis, University of Princeton, 1947.Google Scholar
Henkin, Leon, The completeness of the first-order functional calculus, this Journal, vol. 14 (1949), no. 3, pp. 159–166.Google Scholar
Hilbert, David and Ackermann, Wilhelm, Grundzüge der theoretischen Logik (principles of theoretical logic), Springer-Verlag, Berlin, 1928.Google Scholar
Horn, Alfred, Logic with truth values in a linearly ordered Heyting algebras, this Journal, vol. 34 (1969), no. 3, pp.395–408.Google Scholar
Montagna, Franco, Three complexity problems in quantified fuzzy logic, Studia Logica, vol. 68 (2001), no. 1, pp. 143152.Google Scholar
Montagna, Franco, On the predicate logics of continuous t-norm BL-algebras, Archive for Mathematical Logic, vol. 44 (2005), no. 1, pp. 97114.Google Scholar
Mostowski, Andrzej, Axiomatizability of some many valued predicate calculi, Fundamenta Mathematicae, vol. 50 (1961), no. 2, pp. 165190.Google Scholar
Ono, Hiroakira, Completions of algebras and completeness of modal and substructural logics, Advances in modal logic (Balbiani, Philippe, Suzuki, Nobu-Yuki, Wolter, Frank, and Zakharyaschev, Michael, editors), vol. 4, Kings College Publications, London, UK, 2003, pp. 335353.Google Scholar
Ragaz, Matthias Emil, Arithmetische Klassifikation von Formelmengen der unendlichwertigen Logik, Ph.D. thesis, Swiss Federal Institute of Technology, Zürich, 1981.Google Scholar
Rasiowa, Helena, An algebraic approach to non-classical logics, North-Holland, Amsterdam, 1974.Google Scholar
Rasiowa, Helena and Sikorski, Roman, A proof of the completeness theorem of Gödel, Fundamenta Mathematicae, vol. 37 (1950), pp. 193200.Google Scholar
Rasiowa, Helena and Sikorski, Roman, The mathematics of metamathematics, Panstwowe Wydawnictwo Naukowe, Warsaw, 1963.Google Scholar
Sato, Kentaro, Proper semantics for substructural logics, from a stalker theoretic point of view, Studia Logica, vol. 88 (2008), no. 2, pp. 295324.Google Scholar
Scarpellini, Bruno, Die Nichtaxiomatisierbarkeit des unendlichwertigen Prädikatenkalküls von Łukasiewicz, this Journal, vol. 27 (1962), no. 2, pp. 159–170.Google Scholar