Philosophy of mind is a branch of philosophy that deals with the nature of the mind and its relation to the body and the external world.
The mind–body problem is a paradigmatic issue in philosophy of mind, although a number of other issues are addressed; these include the hard problem of consciousness and the nature of particular mental states.Siegel, S.: The Contents of Visual Experience. New York: Oxford University Press. 2010.Macpherson, F. & Haddock, A., editors, Disjunctivism: Perception, Action, Knowledge, Oxford: Oxford University Press, 2008. Aspects of the mind that are studied include mental events, mental functions, mental properties, consciousness and its neural correlates, the ontology of the mind, the nature of cognition and of thought, and the relationship of the mind to the body.
Dualism and monism are the two central schools of thought on the mind–body problem, although nuanced views have arisen that do not fit either category neatly, with the current emergence of trialism, as a potential school of thought.
Dualism finds its entry into Western philosophy thanks to René Descartes in the 17th century. Substance dualists like Descartes argue that the mind is an independently existing substance, whereas property dualists maintain that the mind is a group of independent properties that emerge from and cannot be reduced to the brain, but that it is not a distinct substance.Hart, W.D. (1996) "Dualism", in Samuel Guttenplan (org) A Companion to the Philosophy of Mind, Blackwell, Oxford, 265–7. Monism is the position that mind and body are ontologically indiscernible entities, not dependent substances. This view was espoused by the 17th-century rationalist Baruch Spinoza.Spinoza, Baruch (1670) Tractatus Theologico-Politicus (A Theologico-Political Treatise). Physicalists argue that only entities postulated by physical theory exist, and that mental processes will eventually be explained in terms of these entities as physical theory continues to evolve. Physicalists maintain various positions on the prospects of reducing mental properties to physical properties (many of whom adopt compatible forms of property dualism), See also See also and the ontological status of such mental properties remains unclear. Idealists maintain that the mind is all that exists and that the external world is either mental itself, or an illusion created by the mind. Neutral monists such as Ernst Mach and William James argue that events in the world can be thought of as either mental (psychological) or physical depending on the network of relationships into which they enter, and dual-aspect monists such as Spinoza adhere to the position that there is some other, neutral substance, and that both matter and mind are properties of this unknown substance. The most common monisms in the 20th and 21st centuries have all been variations of physicalism; these positions include behaviorism, type physicalism, anomalous monism and functionalism.Kim, J., "Mind–Body Problem", Oxford Companion to Philosophy. Ted Honderich (ed.). Oxford:Oxford University Press. 1995. Trialism was introduced in philosophy by John Cottingham in the 20th century, as a reinterpretation of René Descartes dualism by adding a third substance sensation, which is the union of mind and body in what he called Cartesian trialism.
Most modern philosophers of mind adopt either a reductive physicalist or non-reductive physicalist position, maintaining in their different ways that the mind is not something separate from the body. These approaches have been particularly influential in the sciences, especially in the fields of sociobiology, computer science (specifically, artificial intelligence), evolutionary psychology, and the various neurosciences.Pinel, J. Psychobiology, (1990) Prentice Hall, Inc. LeDoux, J. (2002) The Synaptic Self: How Our Brains Become Who We Are, New York:Viking Penguin. Russell, S. and Norvig, P. Artificial Intelligence: A Modern Approach, New Jersey:Prentice Hall. Dawkins, R. The Selfish Gene (1976) Oxford:Oxford University Press. ISBN Reductive physicalists assert that all mental states and properties will eventually be explained by scientific accounts of physiological processes and states. Non-reductive physicalists argue that although the mind is not a separate substance, mental properties supervene on physical properties, or that the predicates and vocabulary used in mental descriptions and explanations are indispensable, and cannot be reduced to the language and lower-level explanations of physical science.Putnam, Hilary (1967). "Psychological Predicates", in W. H. Capitan and D. D. Merrill, eds., Art, Mind and Religion (Pittsburgh: University of Pittsburgh Press.) Continued neuroscientific progress has helped to clarify some of these issues; however, they are far from being resolved. Modern philosophers of mind continue to ask how the subjective qualities and the intentionality of mental states and properties can be explained in naturalistic terms.
Mind–body problem
The mind–body problem concerns the explanation of the relationship that exists between minds, or mental processes, and bodily states or processes. The main aim of philosophers working in this area is to determine the nature of the mind and mental states/processes, and how—or even if—minds are affected by and can affect the body.
Perceptual experiences depend on stimuli that arrive at our various sensory organs from the external world, and these stimuli cause changes in our mental states, ultimately causing us to feel a sensation, which may be pleasant or unpleasant. The subjective features of these sensations are often referred to as qualia, the “what it is like” aspect of conscious experience. For example, someone's desire for a slice of pizza will tend to cause that person to move his or her body in a specific manner and direction to obtain what he or she wants. The question, then, is how it can be possible for conscious experiences to arise out of a lump of gray matter endowed with nothing but electrochemical properties.
A related problem is how someone's propositional attitudes (e.g. beliefs and desires) cause that individual's neurons to fire and muscles to contract. These comprise some of the puzzles that have confronted epistemologists and philosophers of mind from the time of René Descartes.
Dualist solutions to the mind–body problem
Dualism is a set of views about the relationship between mind and matter (or body). It begins with the claim that mental phenomena are, in some respects, non-physical.
A form of property dualism may be found in the ancient Indian philosophical schools of Samkhya and Yoga (ca. 6th c. BCE), as mind and body (Indriya) are different functions of prakriti. Wrongly conflating purusha ("spirit", or better, pure consciousness) with mind or manas (a development of non-conscious prakriti) while correctly distinguishing purusha and prakriti (two eternally-different ontological entities) leads to the erroneous conclusion that Samkhya supports substance dualism. Yet both mind and body are equally non-conscious (jaDaa) in Samkhya and, while they are different developments of prakriti, they are both made up of gunas.
In Western philosophy, the earliest discussions of dualist ideas are in the writings of Plato, who suggested that humans' intelligence (a faculty of the mind or soul) could not be identified with, or explained in terms of, their physical body. However, the best-known version of dualism is due to René Descartes (1641), and holds that the mind is a non-extended, non-physical substance, a "res cogitans". Descartes was the first to clearly identify the mind with consciousness and self-awareness, and to distinguish this from the brain, which was the seat of intelligence. He was therefore the first to formulate the mind–body problem in the form in which it still exists today.
Arguments for dualism The problems of physicalist theories of the mind have led some contemporary philosophers to assert that the traditional view of substance dualism should be defended. From this perspective, this theory is coherent, and problems such as "the interaction of mind and body" can be rationally resolved. The most frequently used argument in favor of dualism appeals to the common-sense intuition that conscious experience is distinct from inanimate matter. If asked what the mind is, the average person would usually respond by identifying it with their self, their personality, their soul, or another related entity. They would almost certainly deny that the mind simply is the brain, or vice versa, finding the idea that there is just one ontological entity at play to be too mechanistic or unintelligible. Modern philosophers of mind think that these intuitions are misleading, and that critical faculties, along with empirical evidence from the sciences, should be used to examine these assumptions and determine whether there is any real basis to them.
According to philosophers like Thomas Nagel and Frank Jackson, the mental and the physical seem to have quite different, and perhaps irreconcilable, properties.Jackson, F. (1982) "Epiphenomenal Qualia." Reprinted in Chalmers, David ed. :2002. Philosophy of Mind: Classical and Contemporary Readings. Oxford University Press. Mental events have a subjective quality, whereas physical events do not. So, for example, one can reasonably ask what a burnt finger feels like, or what a blue sky looks like, or what nice music sounds like to a person. But it is meaningless, or at least odd, to ask what a surge in the uptake of glutamate in the dorsolateral portion of the prefrontal cortex feels like.
A related thought experiment is the Inverted Spectrum Hypothesis (ISH). Which explores the idea of people experiencing colors differently. The ISH suggests that people could have an inverted view of colors. For instance, what one person sees as red, another person might see the opposite on the color wheel, which would be green. However, both people have learned to assign the color that they experience differently to the one term.The idea can be traced back to John Locke, found in his book Essay Concerning Human Understanding published in 1690.Nida-Riimelin, M. (2005). Inverted spectrum. In L. Nadel, Encyclopedia of Cognitive Science (1st ed.). https://access.infobase.com/article/2519744-inverted-spectrum?aid=104024
Philosophers of mind call the subjective aspects of mental events "qualia" or "raw feels". There are qualia involved in these mental events that seem particularly difficult to reduce to anything physical. David Chalmers explains this argument by stating that we could conceivably know all the objective information about something, such as the brain states and wavelengths of light involved with seeing the color red, but still not know something fundamental about the situation – what it is like to see the color red. The phrase “what it is like” is used in philosophy of mind to characterize conscious experience; it originated with Timothy Sprigge and was later popularized by Thomas Nagel.
If consciousness (the mind) can exist independently of physical reality (the brain), one must explain how physical memories are created concerning consciousness. Dualism must therefore explain how consciousness affects physical reality. One possible explanation is that of a miracle, proposed by Arnold Geulincx and Nicolas Malebranche, where all mind–body interactions require the direct intervention of God.
Another argument that has been proposed by C. S. Lewis is the Argument from Reason: if, as monism implies, all of our thoughts are the effects of physical causes, then we have no reason for assuming that they are also the consequent of a reasonable ground. Knowledge, however, is apprehended by reasoning from ground to consequent. Therefore, if monism is correct, there would be no way of knowing this—or anything else—we could not even suppose it, except by a fluke.