Epiphenomenalism

Epiphenomenalism is a position on the mind–body problem which holds that subjective mental events are completely dependent for their existence on corresponding physical and biochemical events within the human body, yet themselves have no influence over physical events. According to epiphenomenalism, the appearance that subjective mental states (such as intentions) influence physical events is an illusion, consciousness being a by-product of physical states of the world. For instance, fear seems to make the heart beat faster, but according to epiphenomenalism the biochemical secretions of the brain and nervous system (such as adrenaline)—not the experience of fear—is what raises the heartbeat. Because mental events are a kind of overflow that cannot cause anything physical, yet have non-physical properties, epiphenomenalism is viewed as a form of property dualism.