In the context of artificial intelligence, "Chain of Thought" refers to a prompting technique where an LLM is encouraged to generate intermediate reasoning steps before arriving at a final answer. This allows models with architectural limitations—which cannot iterate on internal hidden states—to simulate recursion by outputting tokens that serve as a trail of logic. However, recent observations suggest humans may derive similar cognitive benefits from verbalizing their own thought processes during complex tasks.
One developer noted that while common sense suggests speech is slower than silent thinking, articulating ideas aloud serves as a form of "rubber duck debugging." Similar to explaining code to a literal rubber duck, speaking to oneself forces the brain to evaluate unstated assumptions, linearly sort priorities, and identify clear abstractions. For high-complexity puzzles or engineering problems, this practice helps engage System II thinking—the slow, deliberate mental processing required for formal rules—rather than relying solely on subconscious intuition. It also provides a mechanism for backtracking; by naming choices as they occur, it becomes easier to recognize when an arbitrary path has reached a dead end.
Beyond logical structuring, there are physiological and psychological factors involved in vocalized reasoning. Narrating actions can leverage echoic memory to slightly augment working memory capacity, making it easier to retain sequential steps. Some evidence even points toward the Hawthorne effect, where the act of performing under observation (even if only self-imposed) leads to improved performance. While some argue that vocalization might hinder highly creative or deep intuitive leaps, others find it particularly effective at reducing "starting anxiety" by breaking down daunting goals into a trivial sequence of manageable, spoken steps. This approach mirrors educational strategies like guided inquiry, where students are encouraged to speak their thoughts to ensure active mental engagement with the material.