Inertia in Moral and Value Judgments of Large Language Models

Bruce W. Lee, Yeongheon Lee, Hyunsoo Cho


Abstract
Large Language Models (LLMs) behave non-deterministically, and prompting has become a common method for steering their outputs.A popular strategy is to assign a persona to the model to produce more varied, context-sensitive responses, similar to how responses vary across human individuals.Against the expectation that persona prompting yields a wide range of opinions, our experiments show that LLMs keep consistent value orientations.We observe a persistent inertia in their responses, where certain moral and value dimensions (especially harm avoidance and fairness) stay skewed in one direction across persona settings.To study this, we use role-play at scale, which pairs randomized persona prompts with a macro-level analysis of model outputs.Our results point to strong internal biases and value preferences in LLMs, which we call value orientation and inertia. These models warrant scrutiny and adjustment before use in applications where balanced outputs matter.
Anthology ID:
2026.acl-long.1246
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
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Publisher:
Association for Computational Linguistics
Note:
Pages:
27053–27075
Language:
URL:
https://preview.aclanthology.org/ingest-acl/2026.acl-long.1246/
DOI:
Bibkey:
Cite (ACL):
Bruce W. Lee, Yeongheon Lee, and Hyunsoo Cho. 2026. Inertia in Moral and Value Judgments of Large Language Models. In Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), pages 27053–27075, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
Inertia in Moral and Value Judgments of Large Language Models (Lee et al., ACL 2026)
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https://preview.aclanthology.org/ingest-acl/2026.acl-long.1246.pdf
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