Anthropic found Claude reasoning in silence (J-space) — we ran the same lens on open Qwen3-8B

Article automatically generated from technical news.

Anthropic’s research on Claude found a silent internal workspace they call J-space — hidden reasoning that never shows up as visible text. Classic example: the model answers 49 , but inside J-space they caught 21 → 42 → 49 . Important distinction: Chain-of-thought = text you can read J-space = silent concepts in activations (“what’s on its mind”) We fitted the open Jacobian lens (J-lens) on Qwen3-8B, ran it locally, and used it to catch prose drift before tool calls (model lea