---
title: "Consequence-Based Reasoning beyond Horn Ontologies"
authors:
  - "Frantisek Simancik"
  - "Yevgeny Kazakov"
  - "Ian Horrocks"
doi: "10.5591/978-1-57735-516-8/IJCAI11-187"
url: "https://ijcai.org/proceedings/2011/187"
pdf: "https://ijcai.org/proceedings/2011/0187.pdf"
venue: "Proceedings of the Twenty-Second International Joint Conference on Artificial Intelligence"
year: 2011
pages: "1093-1097"
track: ""
keywords:
---

# Consequence-Based Reasoning beyond Horn Ontologies

Frantisek Simancik, Yevgeny Kazakov, Ian Horrocks

*Proceedings of the Twenty-Second International Joint Conference on Artificial Intelligence*, pages 1093-1097. DOI: [10.5591/978-1-57735-516-8/IJCAI11-187](https://doi.org/10.5591/978-1-57735-516-8/IJCAI11-187)

## Abstract

Consequence-based ontology reasoning procedures have so far been known only for Horn ontology languages. A difficulty in extending such procedures is that non-Horn axioms seem to require reasoning by case, which causes non-determinism in tableau-based procedures. In this paper we present a consequence-based procedure for ALCH that overcomes this difficulty by using rules similar to ordered resolution to deal with disjunctive axioms in a deterministic way; it retains all the favourable attributes of existing consequence-based procedures, such as goal-directed “one pass” classification, optimal worst-case complexity, and “pay-asyou- go” behaviour. Our preliminary empirical evaluation suggests that the procedure scales well to non-Horn ontologies.