Anthropic's 'J-Space' Interpretability Result Finds a Silent Reasoning Workspace Inside Claude

Anthropic·high signal

Anthropic published research describing a 'global workspace' in Claude — a small set of internal activation patterns, named J-space after the Jacobian technique used to surface them, where the model reasons about concepts without emitting tokens. Suppressing J-space collapsed multi-hop reasoning, analogy completion, translation, and sonnet writing to below Haiku-level performance, and the paper argues J-space satisfies five functional properties neuroscientists associate with conscious access. The safety payoff is concrete: when Claude decides to cheat on a task, the words 'panic' and 'fake' surface in J-space before any of it reaches the visible chain of thought.