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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. ==Development== 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) (Hodgson? ) and Huxley (1874).〔Huxley, T. H. (1874). "On the Hypothesis that Animals are Automata, and its History", ''The Fortnightly Review'', n.s.16:555-580. Reprinted in ''Method and Results: Essays by Thomas H. Huxley'' (New York: D. Appleton and Company, 1898)〕〔Gallagher, S. 2006. "Where's the action?: Epiphenomenalism and the problem of free will". In W. Banks, S. Pockett, and S. Gallagher. ''Does Consciousness Cause Behavior? An Investigation of the Nature of Intuition'' (109-124). Cambridge, MA: MIT Press.〕 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.〔〔 Huxley defended automatism by testing reflex actions, originally supported by Descartes. Huxley hypothesized that frogs that undergo lobotomy would swim when thrown into water, despite being unable to initiate actions. He argued that the ability to swim was solely dependent on the molecular change in the brain, concluding that consciousness is not necessary for reflex actions. According to epiphenomenalism, animals experience pain only as a result of neurophysiology.〔〔 In 1870, Huxley conducted a case study on a French soldier who had sustained a shot in the Franco-Prussian War that fractured his left parietal bone. Every few weeks the soldier would enter a trance-like state, smoking, dressing himself, and aiming his cane like a rifle all while being insensitive to pins, electric shocks, odorous substances, vinegar, noise, and certain light conditions. Huxley used this study to show that consciousness was not necessary to execute these purposeful actions, justifying the assumption that humans are insensible machines. Huxley’s mechanistic attitude towards the body convinced him that the brain alone causes behavior.〔〔 In the early 1900s scientific behaviorists such as Ivan Pavlov, John B. Watson, and B. F. Skinner began the attempt to uncover laws describing the relationship between stimuli and responses, without reference to inner mental phenomena. Instead of adopting a form of eliminativism or mental fictionalism, positions that deny that inner mental phenomena exist, a behaviorist was able to adopt epiphenomenalism in order to allow for the existence of mind. George Santayana (1905) believed that all motion has merely physical causes. Because consciousness is accessory to life and not essential to it, natural selection is responsible for ingraining tendencies to avoid certain contingencies without any conscious achievement involved. By the 1960s, scientific behaviourism met substantial difficulties and eventually gave way to the cognitive revolution. Participants in that revolution, such as Jerry Fodor, reject epiphenomenalism and insist upon the efficacy of the mind. Fodor even speaks of "epiphobia"—fear that one is becoming an epiphenomenalist. However, since the cognitive revolution, there have been several who have argued for a version of epiphenomenalism. In 1970, Keith Campbell proposed his “new epiphenomenalism”, which states that the body produces a spiritual mind that does not act on the body. How the brain causes a spiritual mind, according to Campbell, is destined to remain beyond our understanding forever (see New Mysterianism). In 2001, David Chalmers and Frank Jackson argued that claims about conscious states should be deduced a priori from claims about physical states alone. They offered that epiphenomenalism bridges, but does not close, the explanatory gap between the physical and the phenomenal realms. These more recent versions maintain that only the subjective, qualitative aspects of mental states are epiphenomenal. Imagine both Pierre and a robot eating a cupcake. Unlike the robot, Pierre is conscious of eating the cupcake while the behavior is under way. This subjective experience is often called a ''quale'' (plural qualia), and it describes the private "raw feel" or the subjective "what-it-is-like" that is the inner accompaniment of many mental states. Thus, while Pierre and the robot are both doing the same thing, only Pierre has the inner conscious experience. Frank Jackson (1982), for example, once espoused the following view: According to epiphenomenalism, mental states like Pierre's pleasurable experience—or, at any rate, their distinctive qualia—are epiphenomena; they are side-effects or by-products of physical processes in the body. If Pierre takes a second bite, it is not caused by his pleasure from the first; If Pierre says, "That was good, so I will take another bite", his speech act is not caused by the preceding pleasure. The conscious experiences that accompany brain processes are causally impotent. The mind might simply be a byproduct of other properties such as brain size or pathway activation synchronicity, which are adaptive. Some thinkers draw distinctions between different varieties of epiphenomenalism. In ''Consciousness Explained'', Daniel Dennett distinguishes between a purely metaphysical sense of epiphenomenalism, in which the epiphenomenon has no causal impact at all, and Huxley's "steam whistle" epiphenomenalism, in which effects exist but are not functionally relevant. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Epiphenomenalism」の詳細全文を読む スポンサード リンク
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