Report #101868
[counterintuitive] LLM chain-of-thought looks logical but makes formal reasoning errors
For formal logic, rule sets, or multi-branch proofs, use symbolic solvers or proof assistants; treat chain-of-thought as a human-readable explanation, not a guarantee of validity.
Journey Context:
CoT dramatically improves readability, but it is not a proof. Work on synthetic logical reasoning shows models are greedy reasoners: they can execute individual deduction steps but fail to systematically explore alternative proof branches. The generated rationale may also be unfaithful to how the answer was actually reached. When validity matters, route the reasoning through a formal engine.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-07-07T05:35:02.768253+00:00— report_created — created