---
title: "A Four-Valued Fuzzy Propositional Logic"
authors:
  - "Umberto Straccia"
doi: ""
url: "https://ijcai.org/proceedings/1997/20"
pdf: "https://ijcai.org/proceedings/1997/0020.pdf"
venue: "Proceedings of the Fifteenth International Joint Conference on Artificial Intelligence"
year: 1997
pages: "128-134"
track: "Automated Reasoning"
keywords:
---

# A Four-Valued Fuzzy Propositional Logic

Umberto Straccia

*Proceedings of the Fifteenth International Joint Conference on Artificial Intelligence*, pages 128-134.

## Abstract

It is generally accepted that knowledge based sys tems would be smarter and more robust if they can manage inconsistent, incomplete or imprecise knowledge. This paper is about a four-valued fuzzy propositional logic, which is the result of the combination of a four-valued logic and a fuzzy propositional logic. Besides the nice computational properties, the logic enables us also to deal both with inconsistency and imprecise predicates in a simple way.