Gilbert Ryle & the Category-mistake

Mark R. Lindner

PHI 389

Philosophy & AI


            In The Concept of Mind, Gilbert Ryle argues that Descartes makes a category-mistake by thinking that there is something called 'mind' over and above a person's behavioral dispositions. My purpose in this essay is to show that Ryle is correct in asserting that Descartes, and many others after him, are guilty of a major category-mistake.

            I intend to show that Ryle is correct by elucidating what a category-mistake is, and how it arises from the misuse or inability to use certain items of vocabulary. I will then show that Descartes makes a category-mistake in his argument that the mind is a non-physical 'thing.' I presuppose that once the category-mistake is exposed the way in which 'mind' is described is not relevant to this argument. It is a fact-of-the-matter whether or not Descartes made a category-mistake. If exposing it destroys "the dogma of the Ghost in the Machine,"[i] as Ryle calls it, then whether or not we have a new theory to replace the old one is not important, although I admit it would be most useful. I will also assume that Bertrand Russell's abductive argument to other minds is correct.

            Ryle's thesis in The Concept of Mind is that the official doctrine, as he calls Cartesian dualism, has central principles that are unsound, and that "conflict with everything we know about minds when we are not speculating about them."[ii] The official doctrine, as Ryle lays it out, maintains that (1) every person has both a body and a mind, (2) that they are normally harnessed together, and that (3) after the death of the body the mind may continue to exist and function. Bodies are believed to exist in space, are subject to mechanical laws, and their states can be observed externally. Minds are not in space, are not subject to mechanical laws, and their workings are inscrutable to other observers. A person thus has two collateral histories, what happens in and to his body, and what happens in and to his mind. A person is supposed to have direct and incontrovertible cognizance of what is momentarily occupying their mind. Thus, bodies and the physical world are external, and the mind becomes internal. This metaphor of 'the inner and outer' gives rise to the assumption that there are two kinds of existence. Physical existence has the necessary feature of being in space and time, and is composed of matter. Mental existence has the necessary feature of being in time, but not in space, and is composed of consciousness. Mind becomes a disembodied 'thing' or "the Ghost in the Machine."[iii] Ryle maintains that Descartes was confronted by conflicting motives. As a scientist he could not help but endorse Galileo's mechanics, but as a man of God, he could not accept, like Hobbes, that human nature differs only in degree from a clock work. Descartes, and others, thus stipulated that since mental words don't signify the occurrence of physical processes, they must signify the occurrence of non-physical processes. But the grammar of mechanics was still used. We talk about the mental, just like the physical, with words like 'thing,' 'stuff,' 'process,' ' change,' 'cause,' ' effect,' etc. But how are minds supposed to affect bodies? Also, concepts, such as responsibility and choice become inapplicable. Thus, Ryle describes the official doctrine as a category-mistake because it "represents the facts of mental life as if they belonged to one logical type or category, when they actually belong to another."[iv]

            I wholeheartedly agree with Gilbert Ryle that Cartesian dualism is guilty of a category-mistake. Ryle's view could be stated that, by misunderstanding how our everyday language functions, we are led to ontological mistakes. By misusing generic or abstract concepts, we tend to postulate as existing entities, which in fact do not exist. By postulating mental operations, as a correlate of physical processes, we are led into a category-mistake that has serious consequences.

            Before we can proceed much further though, we must expose just what a category-mistake is. A category-mistake arises when things or facts of one kind are presented as if they belonged to another. According to Ryle, "the logical type or category to which a concept belongs is the set of ways in which it is logically legitimate to operate with it."[v] An example would be if one were to say, "My pain is green" for pain is not the sort of thing that can be green. Another example is if a visitor to ISU, after being shown the Bone Student Center, Milner Library, the various colleges, the students and faculty, the ISU Farm, and other assorted ISU property, was to still ask "But where is the University?" This would be a category-mistake because the university is not an entity over and above the people and property, it just is the people and property. Two citizens who pay taxes belong to the same category but the average taxpayer does not. As long as the citizens continue to misconstrue the 'average taxpayer' they will think of him as some peculiarly ghostly additional taxpayer. It is an essential part of Ryle's thesis that mind-body dualism is an illusion produced by this type of misuse of our ordinary language. There is a logical absurdity in the concept of the mind having a parallel, non-material existence of its own corresponding to the material existence of the body. If one were to suppose that the mind does have its own parallel existence to the body, how is the mind supposed to affect the body, how is the body supposed to affect the mind, and how is one mind supposed to affect another? Ryle cashes his positive arguments out in terms of behaviorism, but as I presupposed, this is not critical to whether or not the absurdities of the official doctrine arise as a consequence of a category-mistake. Ryle argues that Descartes makes this mistake by thinking that there is something called the 'mind' over and above a person's behavioral dispositions. When we see a person strumming their chin, eyes turned to the ceiling, we say they are 'thinking.' We commit a category-mistake when we then suppose that there is something going on other than the strumming of a chin and eyes looking upward, something called 'thinking.' For Ryle, thinking is nothing more than a certain set of behavioral dispositions (to strum one's chin and look upward) -- there is no further mental event called 'thinking' going on. Mind cannot be the cause of behavior because it is behavior. People learn and use mental concepts such as belief, desire, pain, anger, etc. with a great amount of ease. They must refer to patterns that include bodily behavior, which everyone can see, and not to processes in a soul which is hidden from view. Since we observe these patterns in one another's behavior, we can know other person's have mental states like ours (Russell's abductive argument). Minds do not belong to the category of 'thing.' Minds are not 'things.'

            But, the Cartesian argues that there are physical, and that there are mental processes. Ryle, and I agree. Both propositions are true. Ryle maintains that "the phrase 'there occurs mental processes' does not mean the same sort of thing as 'there occur physical processes', and, therefore, that it makes no sense to conjoin or disjoin the two."[vi] The premise of the official doctrine that there are physical causes of bodily movement and that there are mental causes of bodily movement can not be conjoined logically as Descartes, and others, do. Although the premises are true, the conclusion is false. Thus, Descartes argument is invalid.

            I have shown that Ryle is correct in asserting that Descartes, and many others, are guilty of a major category-mistake by asserting that there is something called 'mind' over and above a person's behavioral dispositions. I elucidated what a category-mistake is, and have shown how it arises from the misuse or inability to use certain items of vocabulary, specifically by conjoining two terms of different categories as if they were of the same. This move is not logically valid.



[i] The Concept of Mind, p. 26.

[ii] Ibid., p. 23.

[iii] Ibid., p. 26.

[iv] Ibid., p. 26.

[v] Ibid., p. 8.

[vi] Ibid., p. 30.