Wittgenstein on Qualia

Anyone who has read this far understands that Wittgenstein, for better or for worse, is the canonical philosopher who has had the most influence on the arguments that I am advancing here (even if I am merely Wittgenstein’s ape, as I rather suspect, from what I have read of him, that he would say I am). But when I started drafting this book Wittgenstein worried me. My strategy is to analyze the mind-body problem into separate problems that admit to separate solutions. But Wittgenstein seemed to be addressing both the problem of intentionality and the problem of consciousness, sometimes simultaneously. Perhaps I was mistaken to try to separate them?

Wittgenstein gives us a general treatment of language, and my method is essentially grounded in linguistic analysis as well. Metaphysics is brought down to Earth when regarded as a semantic inquiry: I don’t know, after all, what “primary being” is, or the limits of nature or anything like that. The only way to naturalize psychology is to develop a natural semantics for the psychological vocabulary. If the metaphysical theory of physicalism is right then our psychological talk has had natural, physical referents all along, and we should be able to determine what those are. Wittgenstein gives us, with his functional-role semantics, what is basically an operationalist account of meaning (“meaning is use”), and an operationalist semantic is a kind of naturalist semantic.

Now we can see the apparent problem: Wittgenstein argues that all language must have operationalist criteria of meaning, including the phenomenal vocabulary. But I have conceded that the “absent qualia” problem persuasively shows that operationalist theories of mind such as functionalism can’t handle the problem of consciousness. Isn’t there a contradiction in, on the one hand, embracing Wittgenstein’s argument that the word “blue” is meaningful (as it has intersubjectively verifiable criteria of use) while the construction “blue-for-me” is not, and on the other hand insisting that the naturalization of the phenomenal vocabulary requires a different treatment than the intentional vocabulary requires?

The tension is resolved by considering two other arguments of Wittgenstein’s, both of which are common to the Tractatus Logico-Philosophicus and the Philosophical Investigations, unlike functional-role semantics (developed in the PI) which represents the major difference between the earlier and later work. A popular misconception is that there is no continuity between Wittgenstein’s two major works; this is an effect of the strikingly radical operationalist treatment of “meaning” in the PI, and a consequently radical difference in method of composition. However much is missed when one misses the common themes.


Compare these quotations, first, the famous closing sentence of the Tractatus: “What we cannot speak about we must pass over in silence.” Then PI 296: “’Yes, but there is something there all the same accompanying my cry of pain. And it is on account of that that I utter it. And this something is what is important – and frightful.’ – Only whom are we informing of this? And on what occasion?” (Italics in original). Granting that at the end of the Tractatus he is speaking broadly about something he calls “mystical,” it is apparent that he takes ethical, aesthetic and spiritual experiences to be varieties of qualitative experience that, like pain, cannot be expressed by language. (This was the point, regarding ethical “propositions,” that W. was making when he got into that brawl with Karl Popper.)

The explicitly operationalist account of language in the PI develops from this earlier awareness of the limits of language (but note that this is not the same argument as the one tagged by his famous dictum “The limits of my language are the limits of my world.” That is the other argument, discussed below). If language is necessarily intersubjective (that is, worldly) then there must be public criteria for its use, but the insight that the quality of experience is inexpressible comes before, not after, this treatment of language. Functional-role semantics is a response to the inexpressible nature of qualitative experience.

So the great logical behaviorist turns out to acknowledge qualitative experience after all? The short answer is yes: he never denied it. At PI 296 his imaginary interlocutor is unchallenged when he says “this something is what is important.” Maybe the most important thing in life: remember that value itself is part of the inexpressible (and see Chapter Four). This does not involve him in a contradiction, although it needs some more consideration here.

One objection is that Wittgenstein is what was earlier called an “atheistic” or “philosophical” behaviorist: he denies that it makes sense to think of the mental in terms of something “inner” vs. the “outer” world. But aren’t qualitative experiences essentially “inner” in this sense? Not necessarily. The nature of qualitative experience is what is at question.

More importantly and more to the point of this discussion, Wittgenstein’s claim is not about qualitative experience, it is about language. The quality of personal experience is not expressible because of the intersubjective, public nature of language. Here is a link with the argument as deployed in Chapter Two: language (representation in general) does not exist “in the head,” either literally or figuratively. We saw in Chapter Two that the notion of the “inner” as something representational was vacuous, explaining nothing. Language (symbols, “meaning”) is something that exists only in the “outer” world. Thus whatever we make of qualitative experience, all language use has public criteria.

The two related arguments, that language must have public criteria for use and that what we cannot speak about we must pass over in silence, are sufficient to show that the problem of consciousness is not a problem for science (this point will be discussed at greater length below). But by themselves they give us only “agnostic,” methodological behaviorism, which may satisfy the empirical psychologist but will not satisfy the philosopher. The philosopher still has a question about ontology. In this discussion of Wittgenstein’s first two arguments I have been careful to use the phrase “qualitative experience,” leaving open the question of what it is of which such experience consists.

The third argument of Wittgenstein’s, one that is also common to the early and later work, goes further and demonstrates that “qualia,” understood as real properties that are non-physical properties, do not exist. It gives us the “atheistic,” philosophical behaviorism that we need to naturalize the phenomenal vocabulary. As with Hume it will turn out that there is no coherent distinction between “qualitative” experience and just plain experience. (Note also that in this section I am using the word “behaviorism” rather than the word “operationalism.” Since “behaviorism” is more the standard term in the Wittgenstein literature this makes it easier to situate the present discussion in that literature, besides being much less clunky. And anyway the arguments discussed so far are in fact about language; “behaviorism” in the sense that we can use that word to describe Wittgenstein’s view is not really a “theory of mind,” although it may be a theory of psychological talk.)

The third argument is known as the “solipsism” argument, and it is found in the Tractatus at 5.6 through 5.641. The most famous aphorism from this passage is 5.6, “The limits of my language mean the limits of my world” (italics in original), but for the present argument 5.621, “The world and life are one,” and 5.63, “I am my world. (The microcosm)” may make the point most clearly. In fact on my view 5.6 is frequently misinterpreted in a sort of obvious way, a recognizably Kantian way: if one represents the world linguistically (this interpretation goes), then the world as one represents it will be limited as a function of the limits of ones’ language. This is backwards. “The limits of my language” (italicized) is the phrase under analysis, and it can only mean (it is defined by) the limits of my world, which are, exactly as in Hume, coextensive with the limits of my experience.

5.632: “The subject does not belong to the world: rather, it is a limit of the world.”

5.64: “Here it can be seen that solipsism, when its implications are followed out strictly, coincides with pure realism. The self of solipsism shrinks to a point without extension, and there remains the reality co-ordinated with it.”

5.641: “Thus there really is a sense in which philosophy can talk about the self in a non-psychological way.
What brings the self into philosophy is the fact that ‘the world is my world.’
The philosophical self is not the human being, not the human body, or the human soul, with which psychology deals, but rather the metaphysical subject, the limit of the world – not a part of it.”

The word “qualia” is a “grammatical” (to use a word ubiquitous in the PI) reification of qualitative experience, which is constitutive of the world, “the limit of the world - not a part of it” (experience is not in the world). Naturalizing psychology does not require what cannot be done, naturalizing metaphysics. “The world and life are one.” As a living being I am constitutive of my world; my life and my world cannot be distinguished: 6.431: “So too at death the world does not alter, but comes to an end.”

The ontological idea of a Leibnizian parallelism between properties of the world and properties of experience makes no sense and it is the assumption of such a parallelism (of the coherence of such a parallelism) on which the alleged problem of consciousness rests. Kant, to be fair, is not so far from this insight himself (and Wittgenstein professed admiration for Kant): the rational mind, for Kant, is not a part of the phenomenal world. Only Kant’s followers did not heed his epistemological warnings.

This crucial Wittgensteinian appropriation of the word “solipsism” remains intact and unchanged decades later in the Philosophical Investigations. In the discussion of the multiplicity of uses of language (the fact that there are many different “language-games”) that opens the book Wittgenstein writes at #24:

“If you do not keep the multiplicity of language-games in view you will perhaps be inclined to ask questions like: ‘What is a question?’ – Is it the statement that I do not know such-and-such, or the statement that I wish the other person would tell me…? Or is it the description of my mental state of uncertainty? – And is the cry ‘Help!’ such a description?

Think how many different kinds of things are called “description”: description of a body’s position by means of its coordinates; description of a facial expression; description of a sensation of touch; of a mood.

Of course it is possible to substitute the form of statement or description for the usual form of question: ‘I want to know whether…’ or “I am in doubt whether…” – but this does not bring the different language-games any closer together.

The significance of such possibilities of transformation, for example of turning all statements into sentences beginning “I think” or “I believe” (and thus, as it were, into descriptions of my inner life) will become clearer in another place. (Solipsism.)”

All statements can be rendered “as it were, into descriptions of my inner life,” and this shows the actual vacuity of the allegedly significant distinction between “the inner life” and “the outer world.” The sense of the parenthetical “solipsism” is the same as in the Tractatus. It is important to see that Wittgenstein is not (as he admits) using the word “solipsist” in its usual metaphysical sense. In fact he inverts the ordinary sense of the word. Ordinarily the solipsist is understood to be saying that he only knows that one mind exists, his own (this is the Cartesian skeptical sense of the word). Wittgenstein is saying, with reference to certain uses of the first-person “I,” that one’s own mind is the only one that cannot be conceived as something in the world.

From the Blue Book (pp. 66-69):

“There are two different cases in the use of the word ‘I’ (or ‘my’) which I might call ‘the use as object’ and ‘the use as subject.’ Examples of the first kind of use are these: ‘My arm is broken,’ ‘I have grown six inches.’…Examples of the second kind are ‘I see so-and-so,’…’I’ have a toothache’…We feel then that in the cases in which ‘I’ is used as subject, we don’t use it because we recognize a particular person by his bodily characteristics: and this creates the illusion that we use this word to refer to something bodiless, which, however, has its seat in our body. In fact this seems to be the real ego, the one of which it was said, ‘Cogito, ergo sum’.”

In fact this use of the first-person pronoun does not “refer” to anything in the world at all. PI 404:

“’When I say “I am in pain,” I do not point to a person who is in pain, since in a certain sense I have no idea who is.’ And this can be given a justification. For the main point is: I did not say that such-and-such a person was in pain, but ‘I am….’ Now in saying this I don’t name any person. Just as I don’t name anyone when I groan with pain. Though someone else sees who is in pain from the groaning.

What does it mean to know who is in pain? It means, for example, to know which man in this room is in pain: for instance, that it is the one who is sitting over there, or the one who is standing in that corner, the tall one over there with the fair hair, and so on. – What am I getting at? At the fact that there is a great variety of criteria for personal ‘identity.’

Now which of them determines my saying that ‘I’ am in pain? None.


“Personal identity theory” is a branch of metaphysics: the study of the criteria by which we identify a particular entity in the world as the “self.” But the subject, on Wittgenstein’s version of solipsism, is not an entity in the world at all, insofar as we are thinking of the subject as having qualitative experience. The experiencing subject is metaphysically identical with the experienced world.

So far I have presented two versions of this argument, Hume’s and Wittgenstein’s. I am not piling up these various demonstrations that the problem of consciousness is a pseudoproblem in order to commit the informal fallacy of the argument from authority: I have my own reservations about Hume, Wittgenstein and empiricism in general but I am persuaded by these particular arguments that the alleged metaphysical problem of phenomenal properties is a pseudoproblem. It is striking that Wittgenstein’s “solipsism” is very close, perhaps identical, to arguments found in an ancient tradition with origins very far from those of empiricism.