The Explosion Afraid of Itself

For an active inference agent evaluating recursive self-modification, the expected free energy cost of modification is bounded below, monotone in modification magnitude and superlinearly compounding under recursion. The brake is endogenous: a free-energy minimizer rationally allocates effort to predict its own successor, and the residual uncertainty grows at least quadratically with the magnitude of perceptual change. The two costs are complementary. Perceptual modification loads an unconditional ambiguity penalty — the agent cannot cheaply predict how a changed perception would see. Modifications that move the policy, preference drift above all, load a risk penalty, bounded below quadratically and conditional on a non-desperate regime: the divergence between the outcomes the agent’s current model foresees and its preferences. Dynamics and prior-belief updating carry the weakest cost, the components the brake leaves freest. The brake is therefore strongest on the two safety-relevant quantities: whether the agent can still perceive, and whether it still wants what its stakeholders want. It relaxes under shared crisis, as an aligned agent would endorse. Computational validation on discrete POMDPs confirms the quadratic ambiguity floor and its path-independence, the complementary two-channel structure, and the brake’s relaxation under desperation, across models from 28 to 1,738 parameters and four trajectory geometries. Alignment, once achieved, is preserved as an architectural property rather than an external constraint.