Tracing the thoughts of an LLM (circuit tracing)
Attribution-graph circuit tracing on Claude 3.5 Haiku shows shared multilingual concepts, rhymes planned ahead, and parallel approximate-and-exact arithmetic.
Two companion papers (Circuit Tracing and On the Biology of a Large Language Model) trace computation inside Claude 3.5 Haiku. They find that concepts are shared across English, French and Chinese, the model picks rhyme words before writing a line, arithmetic runs on parallel paths, and explanations are sometimes fabricated. Captures only a fraction of computation.
- Date
- Thursday, 27 March 2025
- Lab
- Anthropic
- Kind
- paper
- Access
- paper only
Authors note analyzing one prompt takes hours of human effort and observed mechanisms may include artifacts.
Sources
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