Schoenfeld’s Anatomy of Mathematical Reasoning by Language Models

Ming Li, Chenrui Fan, Yize Cheng, Soheil Feizi, Tianyi Zhou


Abstract
Large language models increasingly expose reasoning traces, yet their underlying cognitive structure and steps remain difficult to identify and analyze beyond surface-level statistics. We adopt Schoenfeld’s Episode Theory as an inductive, intermediate-scale lens and introduce ThinkARM (Anatomy of Reasoning in Models), a scalable framework that explicitly abstracts reasoning traces into functional reasoning steps such as Analysis, Explore, Implement, Verify, etc. When applied to mathematical problem solving by diverse models, this abstraction reveals reproducible thinking dynamics and structural differences between reasoning and non-reasoning models, which are not apparent from token-level views. We further present two diagnostic case studies showing that exploration functions as a critical branching step associated with correctness, and that efficiency-oriented methods selectively suppress evaluative feedback steps rather than uniformly shortening responses. Together, our results demonstrate that episode-level representations make reasoning steps explicit, enabling systematic analysis of how reasoning is structured, stabilized, and altered in modern language models.
Anthology ID:
2026.acl-long.1513
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
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ACL
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Publisher:
Association for Computational Linguistics
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Pages:
32773–32802
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URL:
https://preview.aclanthology.org/ingest-acl/2026.acl-long.1513/
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Cite (ACL):
Ming Li, Chenrui Fan, Yize Cheng, Soheil Feizi, and Tianyi Zhou. 2026. Schoenfeld’s Anatomy of Mathematical Reasoning by Language Models. In Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), pages 32773–32802, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
Schoenfeld’s Anatomy of Mathematical Reasoning by Language Models (Li et al., ACL 2026)
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