Non-conventional conjunctions and implications in fuzzy logic

  • János C. Fodor
  • Tibor Keresztfalvi
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 695)


First, we make some remarks concerning the definition of connectives in fuzzy logic. We point out possible disadvantages of considering exclusively t-norms and t-conorms as proper models for the conjunction and disjunction. Coincidence of S- and R-implications is investigated by solving functional equations for conjunctions. Then, we suggest a constructive approach to axiomatics of the generalized modus ponens (GMP). Besides a special model, a particular class of conjunctions satisfying the axioms for GMP and based on the Hamacher family of t-norms is also characterized. On the other hand, the coincidence of R- and S-implications defined by the members of this class is verified.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1993

Authors and Affiliations

  • János C. Fodor
    • 1
  • Tibor Keresztfalvi
    • 1
  1. 1.Eötvös Loránd UniversityBudapest 112Hungary

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