Epiphenomenalism

Epiphenomenalism is a mind–body philosophy marked by the belief that basic physical events (sense organs, neural impulses, and muscle contractions) are causal with respect to mental events (thought, consciousness, and cognition). Mental events are viewed as completely dependent on physical functions and, as such, have no independent existence or causal efficacy; it is a mere appearance. Fear seems to make the heart beat faster; though, according to epiphenomenalism, the state of the nervous system causes the heart to beat faster. 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.

During the seventeenth century, Rene Descartes argued that animals are subject to mechanical laws of nature. He defended the idea of automatic behavior, or the performance of actions without conscious thought. Descartes questioned how the immaterial mind and the material body can interact causally. His interactionist model (1649) held that the body relates to the mind through the pineal gland.La Mettrie, Leibniz, and Spinoza all in their own way began this way of thinking. The idea that even if the animal were conscious nothing would be added to the production of behavior, even in animals of the human type, was first voiced by La Mettrie (1745), and then by Cabanis (1802), and was further explicated by Hodgson (1870) and Huxley (1874).

Thomas Henry Huxley agreed with Descartes that behavior is determined solely by physical mechanisms, but he also believed that humans enjoy an intelligent life. In 1874, Huxley argued that animals are conscious automata in the Presidential Address to the British Association for the Advancement of Science. Huxley proposed that psychical changes are collateral products of physical changes. He termed the stream of consciousness an “epiphenomenon;” like the bell of a clock that has no role in keeping the time, consciousness has no role in determining behavior.

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