Article abstract: An analytic philosopher and proponent of eliminative materialism, Churchland maintained that advances in the neurosciences and artificial intelligence are the key to understanding cognition. A leading defender of scientific realism, he held that scientific theories present a literally true account of the world, especially of the unobservable world.
Paul Montgomery Churchland, a dual American/Canadian citizen, was born in Vancouver, Canada, in 1942. He studied at the University of British Columbia, Vancouver, from 1960 to 1964, and graduated with a B.A. (honors) in philosophy, physics, and mathematics. From 1964 to 1967, he studied at the University of Pittsburgh, one of the world’s leading centers for studies in the philosophy of science. He received his Ph.D. from this institution in the fields of philosophy of science and philosophy of mind. In 1966, Churchland served as an instructor in philosophy at the University of Pittsburgh at Greensburgh and then moved to the University of Toronto, where he served as a lecturer in philosophy from 1967 to 1969, moving in 1969 to the University of Manitoba, where he rose from assistant professor to full professor.
In 1982-1983, Churchland was a member of the Institute for Advanced Study in Princeton, New Jersey. In 1984, Churchland became a professor of philosophy at the University of California, San Diego. At that university, he served as department chair from 1986 to 1990 and was a member of the Cognitive Science Faculty, a member of the Institute for Neural Computation, and a member of the Science Studies faculty.
An important component of Churchland’s philosophy deals with the metaphysical mind-body problem, posed in its sharpest form by the French philosopher René Descartes, called the father of modern philosophy. Descartes asked: What do human beings have that material objects do not have that allows human beings to cognize, to learn languages, and to learn mathematics? He argues that human beings must have an immaterial, nonspatial mind over and above a material, spatially located brain that inanimate objects and lower life forms do not have. Descartes called this mind “mental substance,” the essence of which is thinking. This substance is to be contrasted with material substance, the essence of which is extension, the occupying of space. These two substances are the basis of Descartes’s metaphysical dualism. (For Descartes, there was also a third substance, divine substance, or God.) These substances have necessary existence and need nothing else for their existence. For Descartes, the separation of material substance from mental substance meant that science (which deals with material substance) would never have to come into conflict with religion (which deals with mental substance, or spirit, or soul). Nevertheless, a problem immediately arose as to the nature of the causal interaction between an immaterial, nonspatial mind and a material, spatial body. Descartes held that the interaction occurred in the pineal gland, but this answer simply postpones the problem rather than solving it. To this day, no generally received answer to this mind-body problem has been provided by philosophers, psychologists, or neuroscientists.
Although few modern scholars hold Descartes’s theory of substance dualism, there are, nevertheless, many varieties of contemporary dualism. Popular dualism, for example, holds that the mind is a spiritual substance yet fully possessed of spatial properties in intimate contact with the brain. Other dualistic theories claim that the mind is a property of the material brain. For example, epiphenomenalism holds that the mind is an emergent property of the brain that is not causal to other events, whereas interactionist property dualism holds that mental states emerge from the brain but can causally interact with the brain and other parts of the material body. A sophisticated form of dualism centers on the notion of supervenience. Things of kind A supervene on things of kind B when the presence or absence of things of kind A is completely determined by the presence or absence of things of kind B. It is sometimes argued that the mental supervenes on the physical but that mental categories are not identical with nor reducible to any physical categories.
In contrast to these dualistic theories, reductive materialism, more often called “the identity theory,” holds that mental states are physical states of the brain. An even more popular materialist theory is functionalism, which holds that the defining feature of any type of mental state is the set of causal relations it bears to environmental effects on the body, other types of mental states, and bodily behavior. So pain, for example, typically results from bodily injury, causes annoyance and distress, and causes wincing, blanching, and the nursing of the injured area. Any state that plays exactly the same functional role is pain, according to functionalism. A third type of materialism is eliminative materialism, which holds that the theory of mental states is impoverished, not simply incorrect. There are no mental states, only brain states.
Eliminative materialism is the philosophical theory held by Churchland. He argues that the position is supported by advances in the neurosciences. Neuroscientists routinely produce color-coded images of the actual patterns of activity in the brain when people read, attend to different features of visual stimuli, encode and retrieve memories, and perform other cognitive tasks. Other neuroscientists produce very detailed maps of the primate cortex that distinguish dozens of specialized processing areas. Much support for eliminative materialism is also found in studies of cases of brain damage, degeneration, and disequilibrium. For example, lesions to the connections between the secondary visual cortex and the secondary auditory cortex of the left hemisphere may result in the inability to identify perceived colors, while lesions to the secondary auditory cortex of the left hemisphere results in the more drastic effect of...
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