---
title: "Fast Algorithms for Lexicographic Inference"
authors:
  - "Jonas Klein"
  - "Matthias Thimm"
doi: "10.24963/ijcai.2026/436"
url: "https://ijcai.org/proceedings/2026/436"
pdf: "https://ijcai.org/proceedings/2026/0436.pdf"
venue: "Proceedings of the Thirty-Fifth International Joint Conference on Artificial Intelligence"
year: 2026
pages: "3917-3925"
track: "Main Track"
keywords:
  - "Knowledge Representation and Reasoning: Non-monotonic reasoning"
---

# Fast Algorithms for Lexicographic Inference

Jonas Klein, Matthias Thimm

*Proceedings of the Thirty-Fifth International Joint Conference on Artificial Intelligence*, pages 3917-3925. DOI: [10.24963/ijcai.2026/436](https://doi.org/10.24963/ijcai.2026/436)

## Abstract

We present two new algorithms for the problem of lexicographic inference from conditional knowledge bases. These algorithms are based on SAT and MaxSAT encodings of the underlying problem of lexicographic comparisons of classical interpretations and require only a polynomial number of SAT solver calls. In our experimental evaluation we show that our new algorithms signficantly outperform the state of the art.