Language Is Not the Medium for Logical Thinking
ValerioCapraro · x · 2026-07-15
This post summarizes a PNAS paper addressing the core question: Does logical reasoning depend on natural language?
The study combines two types of evidence:
- Brain imaging of healthy adults: Inductive and deductive reasoning did not significantly engage language networks.
- Two patients with damaged language networks and severe aphasia: They performed poorly on grammar and language tests (often near random) but maintained strong logical reasoning abilities.
The paper also provides specific task results: The two patients could infer hidden rules from changing number sequences, scoring 19/25 and 39/40 respectively. They also scored 25/30 and 26/30 on non-verbal matrix reasoning, above the norm for their age group.
Therefore, the author concludes that natural language is not the medium for formal logical thinking. Language serves more for expression and communication, rather than being the underlying mechanism that generates understanding and reasoning. The original post extends this conclusion to the modern question of "whether talking machines are actually thinking."
Related event: PNAS Study: Logical Reasoning Does Not Rely on Natural Language(2 posts)→
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