Extent of Chain-of-Thought Faithfulness to Underlying Computation
Determine the degree to which chain-of-thought outputs generated by large language models faithfully represent the models' underlying computational processes that produce their final answers.
References
While current reasoning LLMs produce chain-of-thought (CoT) outputs that ostensibly reflect their reasoning, it remains unclear to what extent these outputs faithfully represent the model's true computational process \citep{lanham2023measuring, barez2025chain, chen2025reasoning}.
Ensuring that reasoning traces are consistently faithful remains an open challenge.
This leaves an unresolved tension: how to convey that certain reasoning steps influence answers without implying that their text can be read as meaningful.
The research gap is not exposing reasoning traces, which is done, but establishing whether exposed traces can be trusted as evidence, which is open.
It is, however, unclear if the rationales the models give are faithful: They might just be post-hoc rationalizations.
Absent ground truth, how to measure CoT faithfulness remains unsettled.
We cannot rule out, however, that the invalid generations would have behaved differently.