---
title: "Refutation in Dummett Logic Using a Sign to Express the Truth at the Next Possible World"
authors:
  - "Guido Fiorino"
doi: "10.5591/978-1-57735-516-8/IJCAI11-151"
url: "https://ijcai.org/proceedings/2011/151"
pdf: "https://ijcai.org/proceedings/2011/0151.pdf"
venue: "Proceedings of the Twenty-Second International Joint Conference on Artificial Intelligence"
year: 2011
pages: "869-873"
track: ""
keywords:
---

# Refutation in Dummett Logic Using a Sign to Express the Truth at the Next Possible World

Guido Fiorino

*Proceedings of the Twenty-Second International Joint Conference on Artificial Intelligence*, pages 869-873. DOI: [10.5591/978-1-57735-516-8/IJCAI11-151](https://doi.org/10.5591/978-1-57735-516-8/IJCAI11-151)

## Abstract

In this paper we use the Kripke semantics characterization of Dummett logic to introduce a new way of handling non-forced formulas in tableau proof systems. We pursue the aim of reducing the search space by strictly increasing the number of forced propositional variables after the application of non-invertible rules. The focus of the paper is on a new tableau system for Dummett logic, for which we have an implementation.