Skip to main content

Towards Fuzzy Type Theory with Partial Functions

  • Conference paper
  • First Online:
Book cover Advances in Fuzzy Logic and Technology 2017 (EUSFLAT 2017, IWIFSGN 2017)

Abstract

This paper is a study of fuzzy type theory (FTT) with partial functions. Out of several possibilities we decided to introduce a special value “\(*\)” which represents “undefined”. In the interpretation of FTT, this value lays outside of the corresponding domain. In the syntax, it is naturally represented by the description operator acting on the empty (fuzzy) set which, of course, has no element and so, choosing an element from its kernel gives no result, i.e., it is undefined. We will demonstrate that our approach leads to reasonable characterization of the undefinedness. We will also show that any consistent theory of FTT has a model.

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

Access this chapter

Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 169.00
Price excludes VAT (USA)
  • Available as EPUB and PDF
  • Read on any device
  • Instant download
  • Own it forever
Softcover Book
USD 219.99
Price excludes VAT (USA)
  • Compact, lightweight edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Notes

  1. 1.

    Note that this “\(*\)” is a different element from “\(*\)” introduced for truth values.

  2. 2.

    Recall that the description operator represents, in fact, the defuzzification operation (cf. [14, Chapt. 3]).

References

  1. Andrews, P.: An Introduction to Mathematical Logic and Type Theory: To Truth Through Proof. Kluwer, Dordrecht (2002)

    Book  MATH  Google Scholar 

  2. Duží, M., Jespersen, B., Materna, P.: Procedural Semantics for Hyperintensional Logic. Springer, Dordrecht (2010)

    MATH  Google Scholar 

  3. El-Zekey, M.: Representable good EQ-algebras. Soft Comput. 14, 1011–1023 (2009)

    Article  MATH  Google Scholar 

  4. El-Zekey, M., Novák, V., Mesiar, R.: On good EQ-algebras. Fuzzy Sets Syst. 178, 1–23 (2011)

    Article  MathSciNet  MATH  Google Scholar 

  5. Farmer, W.M.: A partial functions version of Church’s simple theory of types. J. Symb. Log. 55, 1269–1291 (1990)

    Article  MathSciNet  MATH  Google Scholar 

  6. Lappiere, S.: A functional partial semantics for intensional logic. Notre Dame J. Form. Log. 33, 517–541 (1992)

    Article  MathSciNet  Google Scholar 

  7. Lepage, F.: Partial functions in type theory. Notre Dame J. Form. Log. 33, 493–516 (1992)

    Article  MathSciNet  MATH  Google Scholar 

  8. Novák, V.: Descriptions in the full fuzzy type theory. Neural Netw. World 5, 559–565 (2003)

    Google Scholar 

  9. Novák, V.: On fuzzy type theory. Fuzzy Sets Syst. 149, 235–273 (2005)

    Article  MathSciNet  MATH  Google Scholar 

  10. Novák, V.: EQ-algebra-based fuzzy type theory and its extensions. Log. J. IGPL 19, 512–542 (2011)

    Article  MathSciNet  MATH  Google Scholar 

  11. Novák, V.: Fuzzy type theory, descriptions, and partial functions. In: Galichet, S., Montero, J., Mauris, G. (eds.) Proceedings of 7th International Conference EUSFLAT-2011 and LFA-2011, pp. 189–195. Atlantis Press, Amsterdam (2011)

    Google Scholar 

  12. Novák, V.: Fuzzy type theory with partial functions. Fuzzy Sets Syst. (submitted)

    Google Scholar 

  13. Novák, V., de Baets, B.: EQ-algebras. Fuzzy Sets Syst. 160, 2956–2978 (2009)

    Article  MathSciNet  MATH  Google Scholar 

  14. Novák, V., Perfilieva, I., Dvořák, A.: Insight into Fuzzy Modeling. Wiley, Hoboken (2016)

    Book  MATH  Google Scholar 

  15. Tichý, P.: Foundations of partial type theory. Rep. Math. Log. 14, 59–72 (1982)

    MathSciNet  MATH  Google Scholar 

Download references

Acknowledgment

This paper was supported by the grant 16-19170S of GAČR, Czech Republic.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Vilém Novák .

Editor information

Editors and Affiliations

Rights and permissions

Reprints and permissions

Copyright information

© 2018 Springer International Publishing AG

About this paper

Cite this paper

Novák, V. (2018). Towards Fuzzy Type Theory with Partial Functions. In: Kacprzyk, J., Szmidt, E., Zadrożny, S., Atanassov, K., Krawczak, M. (eds) Advances in Fuzzy Logic and Technology 2017. EUSFLAT IWIFSGN 2017 2017. Advances in Intelligent Systems and Computing, vol 643. Springer, Cham. https://doi.org/10.1007/978-3-319-66827-7_3

Download citation

  • DOI: https://doi.org/10.1007/978-3-319-66827-7_3

  • Published:

  • Publisher Name: Springer, Cham

  • Print ISBN: 978-3-319-66826-0

  • Online ISBN: 978-3-319-66827-7

  • eBook Packages: EngineeringEngineering (R0)

Publish with us

Policies and ethics