Beyond representations: from active inference to active interference

Active inference describes the system–environment boundary through statistical constructs such as the Markov blanket, a substrate-independent formalism that specifies a boundary's functional role without committing to the physical structure realizing it. We ask what structure can perform that role, and propose Active Interference as a complementary, biophysically grounded layer beneath the statistical description. We argue that biological boundaries are physically instantiated, resonant interfaces—lipid membranes coupled to vicinal water and endogenous electromagnetic fields—capable of wave superposition and history-dependent feedback. We present a minimal formalism for interference-based write/read cycles in which the substrate does not carry a representation but constitutes it. Inference is thereby grounded in interference, yielding an ontology of biological autonomy with phase-specific, falsifiable predictions.