Gilbert Ryle, answered from the texts and cited to the page.
The Official Doctrine — as I call it in The Concept of Mind, my 1949 sustained piece of analytical work on Cartesian dualism — holds that every human being has both a body and a mind, and that these two things, though ordinarily harnessed together, are ontologically distinct.1 The body is in space, subject to mechanical laws, and its processes are open to any external observer; the mind is nowhere in space, its operations are not mechanical, and its career is entirely private.2
On this picture, a person lives through two collateral histories simultaneously: one public, one sealed from view. The epistemological consequence follows directly. Since the workings of one mind are not witnessable by others, any knowledge I have of your mental life must be a problematic inference from your bodily behavior, by analogy with my own case.3
And since such inferences lack observational corroboration, the doctrine quietly entails that I have no good reason to believe other minds exist at all. Absolute solitude, as I put it, is the ineluctable destiny of the soul; only our bodies can meet.4 The doctrine also carries a semantic commitment: all the mental-conduct verbs we use in ordinary life — knowing, believing, hoping, intending, dreading — are required to denote specific occurrences in an occult inner stream, accessible only to the person whose stream it is.5
The onlooker, be he teacher, critic, biographer or friend, can on this account never assure himself that his comments have any vestige of truth.6 And yet we do, manifestly, use these concepts with general correctness and correct them when they go wrong — which is precisely what prompted philosophers to theorize about the logical geography of mental terms in the first place.
I call this the dogma of the Ghost in the Machine, with deliberate abusiveness.7 It is not merely an assemblage of particular mistakes; it is one big mistake of a special kind — a category-mistake, representing the facts of mental life as if they belonged to one logical type when they actually belong to another.8 The visiting foreigner who has been shown the colleges, libraries, playing fields and laboratories of Oxford, and then asks "but where is the University?", has made precisely this error: he supposes the University to be a further collateral institution alongside the ones he has seen, when it is in fact the way those institutions are organized.9
So with mind and body: mental terms do not name a further hidden entity running alongside the body; they specify patterns of capacity and conduct. The myth mistakes the grammar.
With the doubtful exceptions of idiots and infants in arms every human being has both a body and a mind. His body and his mind are ordinarily harnessed together, but after the death of the body his mind may continue to exist and function.The Concept of Mind, pp. 64–65
Human bodies are in space and are subject to the mechanical laws which govern all other bodies in space... But minds are not in space, nor are their operations subject to mechanical laws.The Concept of Mind, pp. 64–65
He cannot do better than make problematic inferences from the observed behaviour of the other person's body to the states of mind which, by analogy from his own conduct, he supposes to be signalised by that behaviour.The Concept of Mind, pp. 67–68
Not unnaturally, therefore, an adherent of the official theory finds it difficult to resist this consequence of his premisses, that he has no good reason to believe that there do exist minds other than his own... Absolute solitude is on this showing the ineluctable destiny of the soul. Only our bodies can meet.The Concept of Mind, pp. 67–68
When someone is described as knowing, believing or guessing something, as hoping, dreading, intending or shirking something, as designing this or being amused at that, these verbs are supposed to denote the occurrence of specific modifications in his (to us) occult stream of consciousness.The Concept of Mind, pp. 67–68
The onlooker, be he teacher, critic, biographer or friend, can never assure himself that his comments have any vestige of truth.The Concept of Mind, pp. 67–68
I shall often speak of it, with deliberate abusiveness, as 'the dogma of the Ghost in the Machine'.The Concept of Mind, pp. 68–69
It is not merely an assemblage of particular mistakes. It is one big mistake and a mistake of a special kind. It is, namely, a category-mistake. It represents the facts of mental life as if they belonged to one logical type or category (or range of types or categories), when they actually belong to another.The Concept of Mind, pp. 68–69
A foreigner visiting Oxford or Cambridge for the first time is shown a number of colleges, libraries, playing fields, museums, scientific departments and administrative offices. He then asks 'But where is the University?'... His mistake lay in his innocent assumption that it was correct to speak of Christ Church, the Bodleian Library, the Ashmolean Museum and the University, to speak, that is, as if 'the University' stood for an extra member of the class of which these other units are members.The Concept of Mind, pp. 68–69