Evaluating Theory-of-Mind in Large Language Models Through Opponent Modeling

Conference Paper (2025)
Author(s)

Emre Kuru (Özyeğin University)

Anll Dogru (Özyeğin University)

Merve Dogan (Özyeğin University)

Reyhan Aydogan (Özyeğin University, TU Delft - Interactive Intelligence)

Research Group
Interactive Intelligence
DOI related publication
https://doi.org/10.1145/3717511.3747081
More Info
expand_more
Publication Year
2025
Language
English
Research Group
Interactive Intelligence
Publisher
ACM
ISBN (print)
979-8-4007-1508-2
Reuse Rights

Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.

Abstract

Theory-of-Mind (ToM), the ability to infer the mental states, goals, and preferences of others - is a core component of human social intelligence. In this work, we investigate whether Large Language Models (LLMs) exhibit ToM capabilities in the context of strategic interaction. We frame opponent modeling in negotiation as a grounded and interpretable ToM task, where a model must infer an agent's preferences by observing offer exchanges during the negotiation. We guide LLMs to interpret offer histories and infer latent utility representations, including issue and value weights. We conduct a comprehensive evaluation of state-of-the-art LLMs across multiple negotiation domains. Our results show that LLMs can successfully recover opponents unknown preferences and in some cases even outperform classical opponent modeling baselines, even without task-specific training. These findings offer new evidence of LLMs' emerging capacity for social reasoning and position opponent modeling as a practical benchmark for evaluating Theory-of-Mind in foundation models.