Paraconsistent Reasoning with Words

  • Alicja S. Szalas
  • Andrzej Szałas
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5070)


Fuzzy logics are one of the most frequent approaches to model uncertainty and vagueness. In the case of fuzzy modeling, degrees of belief and disbelief sum up to 1, which causes problems in modeling the lack of knowledge and inconsistency. Therefore, so called paraconsistent intuitionistic fuzzy sets have been introduced, where the degrees of belief and disbelief are not required to sum up to 1. The situation when this sum is smaller than 1 reflects the lack of knowledge and its value greater than 1 models inconsistency.

In many applications there is a strong need to guide and interpret fuzzy-like reasoning using qualitative approaches. To achieve this goal in the presence of uncertainty, lack of knowledge and inconsistency, we provide a framework for qualitative interpretation of the results of fuzzy-like reasoning by labeling numbers with words, like true, false, inconsistent, unknown, reflecting truth values of a suitable, usually finitely valued logical formalism.


fuzzy logics four-valued logics paraconsistent reasoning reasoning with words 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2009

Authors and Affiliations

  • Alicja S. Szalas
    • 1
  • Andrzej Szałas
    • 2
    • 3
  1. 1.School of Biological Sciences, Royal HollowayUniversity of LondonEgham, SurreyUK
  2. 2.Institute of InformaticsWarsaw UniversityWarsawPoland
  3. 3.Department of Computer and Information ScienceLinköping UniversityLinköpingSweden

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