Oliver Steele

One router over a shared value slot handles every mental space language builds: counterfactual, belief, fictional, temporal. A DAS subspace trained to control one space type controls the others too (cross-type transfer 0.78–0.88, chance 0.50), on three model families. The router is low-rank, composes additively with entity identity, and drives inference, not just what the model reports.

Belief–reality separation lives in routing, not in the value slot itself: intervening on the slot moves a reality readout as strongly as a belief one. Two routes fill it — an asserted belief binds directly; a derived belief arrives by visibility-gated lookback — and a subspace trained on either route steers the other. Holds across three architectures; the behavior emerges between 3B and 7B parameters.