After spending the last few weeks reading through the reasoning literature, I noticed a trend that seems worth discussing. For the past 2–3 years, a large fraction of progress in LLM reasoning came from making models generate more intermediate thoughts. Chain-of-Thought prompting (Wei et al., 2022) pushed PaLM 540B from roughly 18% to 58% on GSM8K. Self-Consistency added another 17.9 percentage points by exploring multiple reasoning paths before committing to an answer. Tree-of-Thoughts later showed that GPT-4's success rate on Game of 24 could jump from 4% to 74% when reasoning was reformulated as search rather than a single chain. DeepSeek-R1 and OpenAI's o1 pushed the idea even further by allocating substantial test-time compute to reasoning itself. Taken together, these results seemed to point in the same direction: giving models additional reasoning trajectories, search paths, or thinking steps often improved outcomes. Recent work increasingly asks whether those traces are actually necessary.…