Physicalism: The View That Everything Is Physical
Physicalism holds that everything that exists is physical or fully determined by the physical — challenged in philosophy of mind by the hard problem of consciousness and p-zombies.
Physicalism is the metaphysical position that everything that exists is physical, or fully determined by the physical. In philosophy of mind, it holds that mental states — thoughts, experiences, consciousness — are identical to or supervene on brain states: there can be no mental difference without a physical difference. ## Variants - **Type identity theory**: Each mental type (e.g., pain) *is* a specific brain state type - **Functionalism**: Mental states are defined by their causal roles, not their physical substrate — pain is whatever plays the "pain role" in the system - **Eliminative materialism**: Folk-psychological categories (beliefs, desires) are simply wrong and will be replaced by neuroscience ## Challenges The The Hard Problem of Consciousness: Why Physical Brains Create Subjective Experience (Chalmers, 1995) poses the deepest challenge: even a complete physical account of the brain seems to leave unexplained *why* there is subjective experience. The The Philosophical Zombie (P-Zombie) thought experiment — a being physically identical to a human but with no inner experience — is designed to show that physical facts alone don't necessitate consciousness. Physicalists respond that the zombie scenario is not genuinely conceivable (despite seeming so), or that the explanatory gap is epistemic rather than ontological — we may lack the concepts to bridge it, but that doesn't mean consciousness isn't physical.