Do Morals Guide How LLMs Think? The Role of Ethical Perspectives in General Problem Solving

Iseo Kim, Eunjin Hong, Juae Kim


Abstract
This study investigates how different moral conditions influence the general problem-solving capabilities of Large Language Models (LLMs). We aim to explore whether the role of morality as a cognitive function operating in human decision-making can be extended to LLMs. Specifically, we define distinct moral stages based on Kohlberg’s theory of moral development and design prompts to elicit model responses aligned with each corresponding condition. The validity of this alignment is verified using the Defining Issues Test, a human evaluation tool. Subsequently, models reflecting the characteristics of each condition are evaluated using the MMLU benchmark, which requires general problem-solving abilities across various domains. Experimental results show that different moral perspectives lead to changes in the model’s decision-making during general reasoning, reflected in both responses and internal representations. Notably, conditions grounded in more advanced moral stages tend to elicit more thoughtful and reflective problem-solving behavior, which is often associated with enhanced performance. Our study attempts to broaden the concept of LLM morality, which has traditionally only been considered in ethical judgment scenarios. Furthermore, it emphasizes that morality is not merely a means of ensuring safety but a crucial factor that shapes a model’s behavior and thought processes.
Anthology ID:
2026.acl-long.2002
Volume:
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Month:
July
Year:
2026
Address:
San Diego, California, United States
Editors:
Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
Venue:
ACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
43217–43238
Language:
URL:
https://preview.aclanthology.org/ingest-acl/2026.acl-long.2002/
DOI:
Bibkey:
Cite (ACL):
Iseo Kim, Eunjin Hong, and Juae Kim. 2026. Do Morals Guide How LLMs Think? The Role of Ethical Perspectives in General Problem Solving. In Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), pages 43217–43238, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
Do Morals Guide How LLMs Think? The Role of Ethical Perspectives in General Problem Solving (Kim et al., ACL 2026)
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PDF:
https://preview.aclanthology.org/ingest-acl/2026.acl-long.2002.pdf
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