Seeing Isn’t Believing: Mitigating Belief Inertia via Active Intervention in Embodied Agents

Hanlin Wang, Chak Tou Leong, Jian Wang, Wenjie Li


Abstract
Recent advancements in large language models (LLMs) have enabled agents to tackle complex embodied tasks through environmental interaction. However, these agents still make suboptimal decisions and perform ineffective actions, as they often overlook critical environmental feedback that differs from their internal beliefs. Through a formal probing analysis, we characterize this as belief inertia, a phenomenon where agents stubbornly adhere to prior beliefs despite explicit observations. To address this, we advocate active belief intervention, moving from passive understanding to active management. We introduce the Estimate-Verify-Update (EVU) mechanism, which empowers agents to predict expected outcomes, verify them against observations through explicit reasoning, and actively update prior beliefs based on the verification evidence. EVU is designed as a unified intervention mechanism that generates textual belief states explicitly, and can be integrated into both prompting-based and training-based agent reasoning methods. Extensive experiments across three embodied benchmarks demonstrate that EVU consistently yields substantial gains in task success rates. Further analyses validate that our approach effectively mitigates belief inertia, advancing the development of more robust embodied agents. Our code is available at https://github.com/WangHanLinHenry/EVU.
Anthology ID:
2026.findings-acl.1884
Volume:
Findings of the Association for Computational Linguistics: ACL 2026
Month:
July
Year:
2026
Address:
San Diego, California, United States
Editors:
Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
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Findings
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Publisher:
Association for Computational Linguistics
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Pages:
37796–37815
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https://preview.aclanthology.org/ingest-acl/2026.findings-acl.1884/
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Cite (ACL):
Hanlin Wang, Chak Tou Leong, Jian Wang, and Wenjie Li. 2026. Seeing Isn’t Believing: Mitigating Belief Inertia via Active Intervention in Embodied Agents. In Findings of the Association for Computational Linguistics: ACL 2026, pages 37796–37815, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
Seeing Isn’t Believing: Mitigating Belief Inertia via Active Intervention in Embodied Agents (Wang et al., Findings 2026)
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https://preview.aclanthology.org/ingest-acl/2026.findings-acl.1884.pdf
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