Skip to main content
Log in

On two problems of Harvey Friedman

  • Published:
Studia Logica Aims and scope Submit manuscript

Abstract

The paper considers certain properties of intermediate and moda propositional logics.

The first part contains a proof of the theorem stating that each intermediate logic is closed under the Kreisel-Putnam rule ∼x→y∨z/(∼x→y)∨(∼x→z).

The second part includes a proof of the theorem ensuring existence of a greatest structurally complete intermediate logic having the disjunction property. This theorem confirms H. Friedman's conjecture 41 (cf. [2], problem 41).

In the third part the reader will find a criterion which allows us to obtain sets satisfying the conditions of Friedman's problem 42, on the basis of intermediate logics satisfying the conditions of problem 41.

Finally, the fourth part contains a proof of a criterion which allows us to obtain modal logics endowed with Hallden's property on the basis of structurally complete intermediate logics having the disjunction property.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. G. Asser, Einführung in die Mathematische Logik, Teil I, Leipzig 1959.

  2. H. Friedman, One hundred and two problems in mathematical logic, Journal of Symbolic Logic 40 (1975), pp. 113–129.

    Google Scholar 

  3. V. Glivenko, Sur quelques points de la logique de M. Brouwer, Bulletin de la Société Mathématique de Belgique, Ser. 5, 15 (1929), pp. 183–188.

    Google Scholar 

  4. R. Harrop, Concerning formulas of the type A→B ∨ C, A→(Ex) B (x) in intuitionistic formal systems, Journal of Symbolic Logic 25 (1960), pp. 27–32.

    Google Scholar 

  5. S. C. Kleene, Disjunction and existence under implication in elementary intuitionistic formalisms, Journal of Symbolic Logic 27 (1962), pp. 11–18.

    Google Scholar 

  6. G. Kreisel and H. Putnam, Eine Unableitbarkeits-beweismethode für den intuitionistischen Aussagenkalkül, Archiv für Mathematische Logik und Glundlagenforschung 3 (1957), pp. 74–78.

    Google Scholar 

  7. E. Lemmon, A note on Hallden incompletenes, Notre Dame Journal of Formal Logic 7 (1966), pp. 296–300.

    Google Scholar 

  8. L. A. Levin, Some syntactic theorems on the calculus of Medvedev's finite problems, Doklady Akademii Nauk SSSR, Vol. 185, (1969), pp. 32–33.

    Google Scholar 

  9. J. C. C. McKinsey, Systems of modal logics which are not unreasonable in the sense of Hallden, Journal of Symbolic Logic 18 (1953), pp. 109–113.

    Google Scholar 

  10. J. C. C. McKinsey and A. Tarski, Some theorems about the sentential calculi of Lewis and Heyting, Journal of Symbolic Logic 13 (1948), pp. 1–15.

    Google Scholar 

  11. Ú. T. Medvedev, Intérprétaciá logičeskih formul posrédstwam finitnych zadač i sváz' éé s téoréj réalizuémosti, Doklady Akademii Nauk SSSR, Vol. 148 (1963), pp. 771–774.

    Google Scholar 

  12. W. A. Pogorzelski, Structural completeness of the propositional calculus, Bulletin de l'Académie Polonaise des Sciences, Série des Sciences Mathématiques, Astronomiques et Physiques 19 (1971), pp. 349–351.

    Google Scholar 

  13. T. Prucnal, Structural completeness and the disjunction property of intermediate logics, Bulletin of the Section of Logic 4 (1975), pp. 72–73, (abstract).

    Google Scholar 

  14. T. Prucnal, Structural completeness of Medvedev's propositional calculus, Reports on Mathematical Logic 6 (1976), pp. 103–105.

    Google Scholar 

  15. T. Prucnal, Dowód niezawodności reguly Kreisel'a-Putnama, (A proof of the validity of the Kreisel-Putnam's rule, in Polish) Praca zbiorowa “Matematyka”, zbiór artykułów, WSP Kielce, 1977, pp. 3–6.

    Google Scholar 

  16. T. Prucnal, On Friedman's problem in mathematical logic, Bulletin of the Section of Logic 7 (1978), pp. 137–142, (abstract).

    Google Scholar 

  17. H. Rasiowa, An Algebraic Approach to Non-Classical Logic, North-Holland Publishing Company, Amsterdam. PWN-Polish Scientific Publishers, Warszawa 1974.

    Google Scholar 

  18. H. Rasiowa and R. Sikorski, The Mathematics of Metamathematics. PWN Warszawa 1963.

    Google Scholar 

  19. R. Suszko, Konsekwencje inwariantne, (Invariant consequences, in Polish) Proceedings of the Autumn Logic SchoolMiedzygórze 1977, (preprint).

  20. R. Wójcicki, Matrix approach in methodology of sentential calculi, Studia Logica 32 (1973), pp. 7–37.

    Google Scholar 

  21. A. Wroński, Remarks on Hallden completeness of modal and intermediate logics, Bulletin of the Section of Logic 5 (1976), pp. 126–129.

    Google Scholar 

  22. J. Łukasiewicz and A. Tarski, Untersuchungen über den Aussagenkalkül, Comptes Rendus de la Société Sciences et des Lettres de Varsovie, Cl. III., 23 (1930).

Download references

Author information

Authors and Affiliations

Authors

Additional information

Dedicated to Professor Roman Suszko

The author would like to thank professors J. Perzanowski and A. Wroński for valuable suggestions.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Prucnal, T. On two problems of Harvey Friedman. Stud Logica 38, 247–262 (1979). https://doi.org/10.1007/BF00405383

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF00405383

Keywords

Navigation