---
title: "A General Proof Method for First-Order Modal Logic"
authors:
  - "Peter Jackson"
  - "Han Reichgelt"
doi: ""
url: "https://ijcai.org/proceedings/1987/194"
pdf: "https://ijcai.org/proceedings/1987/0194.pdf"
venue: "Proceedings of the Tenth International Joint Conference on Artificial Intelligence"
year: 1987
pages: "942-943"
track: "Reasoning"
keywords:
---

# A General Proof Method for First-Order Modal Logic

Peter Jackson, Han Reichgelt

*Proceedings of the Tenth International Joint Conference on Artificial Intelligence*, pages 942-943.

## Abstract

We present a general sequent-based proof method for first-order modal logics in which the Barcan formula holds. The most important feature of our system is the fact that it has identical inference rules for every modal logic; different modal logics can be obtained by changing the conditions under which two formulas are allowed to resolve against each other . It is argued that the proof method is very natural because these conditions correspond to the conditions on the accessibility relation in Kripke semantics.