An Extension of Gödel Logic for Reasoning under Both Vagueness and Possibilistic Uncertainty

  • Moataz El-Zekey
  • Lluis Godo
Part of the Communications in Computer and Information Science book series (CCIS, volume 298)


In this paper we introduce a logic called FNG~(ℚ) that combines the well-known Gödel logic with a strong negation, rational truth-constants and Possibilistic logic. In this way, we can formalize reasoning involving both vagueness and (possibilistic) uncertainty. We show that the defined logical system is useful to capture the kind of reasoning at work in the medical diagnosis system CADIAG-2, and we finish by pointing out some of its potential advantages to be developed in future work.


Fuzzy Logic Propositional Variable Boolean Formula Possibilistic Logic Necessity Measure 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Moataz El-Zekey
    • 1
  • Lluis Godo
    • 2
  1. 1.Department of Basic Sciences, Faculty of EngineeringBenha UniversityEgypt
  2. 2.IIIA-CSICBellaterraSpain

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