A Hypothesis on the Mechanism of Mental Causation: The Quantum Interface and a Pathway to Strong Naturalistic Dualism

The problem of mental causation remains a central challenge for the philosophy of mind. David Chalmers, having demonstrated the irreducibility of phenomenal experience and introduced the term “naturalistic dualism”, stopped halfway: the ontological status of consciousness (property or substance?) was left unclear, and no mechanism for its causal influence on the physical world was proposed. In this paper we show that a consistent solution to these questions requires us to recognise consciousness as a special kind of entity — ontologically autonomous, underivable from the axioms of physical theory, yet interacting with ordinary (baryonic) matter through the probabilistic channel supplied by quantum mechanics. The quantum interface model describes this channel as bidirectional: the downstream flow realises volitional choice, while the upstream flow supplies the Agent with information about the physical system, thereby providing a direct explanation of the nature of qualia. In this way “naturalistic dualism” acquires a precise meaning and is transformed into strong naturalistic dualism, in which consciousness is not only fundamental but also causally efficacious. We address the main objections and offer a comparative analysis of alternative approaches.