It’s good to have a canonical, in-print version of Dan Dennett’s latest thinking on consciousness (chapter 14 of his latest book) to which those who’ve followed his work over the years can respond. He presents a physicalist case against qualia by considering the experience of an afterimage: red stripes generated by looking at a green and black striped image of an American flag. Here are some key features of his view:
Although qualia are suspect, we definitely have experiences (his emphasis):
How could I be having an experience of a horizontal red stripe unless something somewhere is red and horizontal? 360
Colors can, at least on some occasions, be correctly understood as objective properties of the external world, of things that really exist, as contrasted with properties of non-existent qualia (my emphasis is the underlining):
Qualia are supposed to be somehow the internal subjective properties that we are acquainted with more directly, when we are slightly less acquainted with their normal external causes – real red stripes, and so on in the world. When you make this move, you are positing an internal cause that has the same properties as the intentional objects that normally cause your perceptual beliefs – except that these are private, subjective versions, somehow, of the public, objective properties of redness and so forth. 360-61
There are no such things as qualia, the private phenomenology that some suppose we’re acquainted with when having experiences:
...you must resist the alluring temptation to postulate a panoply of special subjective properties (typically called qualia) to which you (alone) have access. 365
Consciousness, should we identify it with having qualia, is epiphenomenal (does no causal work in controlling behavior):
The postulation of qualia is just doubling up the cognitive work to be done. There is no work (or play) for consciousness to do. 363
We’re not in an observational, epistemic relationship to consciousness:
He [Descartes] got off on the wrong foot, then, by taking the “first person point of view” as his direct, and even infallible, epistemic access to consciousness… 364
Experiences, including sensory experiences of color, are individuated by their contents in our reports of them (his emphasis):
“…If you want to talk about your own mental states, you must identify them by their content: ‘Which idea? My idea of HORSE. Which sensation? My sensation of white.’” 367
In arguing for qualia skepticism, Dan points out that when we have an afterimage of a red stripe, there is nothing red anywhere: not in the world, not in the brain, and not in the mind (there is no red quale rendered in mental “figment”). He says we’re having an experience of a red stripe, but we shouldn’t suppose that anything exists but a physically-instantiated representational episode in the brain that somehow accounts for, or perhaps just is, the experience (pp. 358-363).
But what about the fact that we’re experiencing a red stripe? If there is no red anywhere, how is it we say confidently that the afterimage is red? Indeed, we say this with the same confidence that we say an apple before us appears red. In both cases we’re having an experience involving red, so it isn’t as if the redness of the experienced afterimage is less real than that of the apple. The red of the afterimage isn’t a possible property of a physical object, but experientially it’s on a par with reds that possibly are.
So where is the red of the afterimage? Nowhere, as Dan says. But is it real? Absolutely, since it’s no less real than the red of the apple as we report our experience of the apple. It’s part of the content of the sensory experience of the red stripe afterimage that is somehow a function of representational goings-on in the brain.
What about the redness of the apple? Well, that too is experienced, sensory red, but now in the context of our representing, in consciousness, physical, external objects. The apple gains its status as physical and external by virtue of the fact that our sensory experience of it changes reliably as we manipulate it and move around it, things we can’t do with afterimages. The apple, as qualitatively represented by us in our experience, persists as an identifiable entity though all sorts of transformations of its appearance to us, which is what drives us to credit it with its own mind-independent reality. But we don’t have any other sort of access to it apart from our sensory impressions – our experiences – of it. The experienced apple, then, is a very reliable construction of sensory content, which we naturally and properly construe as corresponding to the fact that it exists apart from that construction. Of course, we normally take the construction to be the apple as it is in itself, which is fine for all practical purposes.
Now, we can pose the same question regarding the experienced red of the apple that we did about the experienced red of the afterimage: where is the red? Again, the correct answer is: nowhere. In response, we might object that since there’s something red over there (the apple), there’s red over there, right? Nope. The red is the sensory content of your (real) experience, a representational achievement of the brain, and that content isn’t located anywhere, although it participates in our locating things in the world. What’s located somewhere are objects like the apple that are represented by you (and any others looking at it) to be there, and represented to be red. But the red isn’t anywhere.
What about qualia? I’d suggest that qualia, properly understood, are simply the discriminable contents of sensory experience - all the tastes, colors, sounds, textures, and smells in terms of which reality appears to us as conscious creatures. They are not, as Dan correctly says, located or rendered in any detectable mental medium. They’re not located anywhere, and we are not in an observational or epistemic relationship to them; rather they are the basic, not further decomposable, hence ineffable elements of the experiences we consist of as conscious subjects. (Because qualia aren’t locatable in the physical world, they don’t appear in scientific explanations of behavior, so we might be tempted to call them epiphenomenal. I think this is a mistake since they aren’t even in a position to be epiphenomenal, but I won’t pursue this point here.)
Dan, a good, sophisticated physicalist, wants everything real to be locatable in the physical external world as vetted by science. What’s really real is what’s in the scientific image, right? But if you believe that we really have experiences, that experiences are specified in terms of content, and that color is among those contents, then the color of the experienced afterimage is as real as experiences. But it isn’t locatable, nor are any of the contents of experience: experiences are not observables. We don’t find them out there in spacetime or when poking around in the brain; we only find objects of various qualitative, quantitative and conceptual descriptions, including the brains with which experiences are associated. But since experiences and their contents are real, this means that not all of what’s real is locatable in the physical, external world.
The reality of red as experiential content is of course originally secured by the apple, since no one would deny it appears red. But we’ve since learned that it appears (very reliably and robustly) red by virtue of the content of the sensory experience we have when we’re in the vicinity of apples. Because we can’t deny that the apple appears red, the existence of experiential content is not in question. And such content isn’t locatable, except insofar as it’s attributed as a property of physical objects located in space, which is what we ordinarily do: the apple appears red, so we take red to be a property of the locatable apple. This is harmless enough and works well in practice, but such naïve physicalism can’t dislodge the fact that colors are, in the end, how those with normal human color vision represent the world. The afterimage example simply draws attention to the fact that real qualitative content need not be a veridical representation.
Is the reality of red as non-locatable experiential content the end of physicalism tout court? Only if we construe such content – which I think is perfectly safe to call qualia – as things, as categorically mental essences or substances that constitute an ontology separate from experiential content itself, something that we somehow inspect and have epistemic access to. This is precisely what Dan rightly says is not the case. If instead we understand qualitative contents such as red to be the terms in which physical objects are represented for us as conscious subjects, not any thing or object that we can further represent, then the basic divide isn’t between a dualist ontology of physical vs. mental substances (what Dan aims to debunk), but of what’s represented vs. the terms of representation. We have the subjective representational reality of qualia (qualitative content) on the one hand, and the objective represented reality of the physical, external world on the other.
If consciousness studies continue to advance (science may be running out of time!), we will eventually figure out which physically- and functionally-characterized representational processes are associated with the arising of experiential content, and may even discover why such content is qualitative. But what’s not going to happen is to find that content as an element of the content vehicles themselves; as Dan says, we’re not going to find red in the brain, or experiences in the brain: there is no “second transduction.” And we only find red “in” the apple as a function of how its light reflectance properties and setting combine with how we represent it, all of which results in our having the experiential content red in the context of other content that constructs the external world for us. This is what it means, and all it could mean, for a property to be objective: to be assigned to what we represent as being a publicly available, physical, mind-independent object.
The temptation for sophisticated physicalists is to dismiss qualitative contents – qualia – as somehow illusory, as unreal, since they don’t appear in the physical world – they aren’t locatable. But although the red stripe of the afterimage is illusory, our experience of it being red is not, since otherwise the conversation about whether the red stripe actually exists couldn’t get started (the experience and its qualitative content are givens in Dan’s account). The physical, external world is delivered to us – appears to us – in terms of such content, but we don’t find the content itself in the world as it thus appears, except as the (naively) attributed properties of objects. Science (and the scientific image) finds no such qualities in the objective world, only the physically-characterized representational vehicles, so as James Tartaglia suggests, philosophers wanting to conform to what science declares to exist may write qualia off as unreal. Dan says (my italics):
We won’t have a complete science of consciousness until we can align our manifest-image identifications of mental states by their contents with scientific-image identifications of the sub-personal information structures and events that are causally responsible for generating the details of the user-illusion that we take ourselves to operate in. 367
Here it seems Dan is suggesting that colors – part of the manifest-image of contentful mental states – are illusions, since they participate in the global user-illusion of consciousness. But it isn’t an illusion that apples and afterimages sometimes appear to be red in our experiences. They really appear red, and so we innocently and conveniently describe them as being red. When we’re conscious and out-and-about, objective reality (the apple) and actual illusions (the red stripe afterimage) appear to us in terms of qualities, and the manifest durability and concreteness of the external, physical world – its palpable thereness – is largely a function of how reliably these qualities, and of course the neural processes that are their content vehicles, get deployed in representing that world. As Dan himself says:
We learn about reality via the categories of colors, sounds, aromas, solid objects, and rainbows… 366
If we grant that experiences are real, as Dan does, it’s difficult to dismiss their non-locatable qualitative content (qualia) as less real than the locatable physical objects they participate in representing to us as conscious subjects.
- Tom Clark, 2/24/17
 Note that color constancy and the reliable geometrical transformations consequent to shifts in our perspective on an object also contribute to the judgment of its being externally real.
 Likewise, we only have sensory access to the very powerful perceptual aids we employ in science, such as telescopes and microscopes and computer monitors and printed diagrams, etc., etc. Science proceeds via the having of sensory experience, intersubjectively agreed upon as being veridical.
 Most folks aren’t fully aware that their experience is representational, the terms in which the external world appears to them as conscious creatures; rather, as naïve realists they suppose that the world is simply there in itself, thus is simply presented, not represented. This of course is how we experience the world: as an unmediated presentation. So we usually and rightly talk about the apple, not our experience of it, even though were it not for experience the apple wouldn’t appear to us.
 Dan notes the ineffability of what he says is the illusory property of sweetness (“no property at all… a benign illusion”), p. 356: “We can recognize it, recall it, dream about it, but we can’t describe it; it is ineffable and unanalyzable.” Although sweetness might be ineffable and unanalyzable, that doesn’t mean it’s illusory, but simply a basic qualitative element of our subjective representational reality. And indeed, on the next page Dan says “The properties of sweetness and cuteness depend on features of our nervous system…,” so it seems sweetness isn’t illusory after all. I think he would agree that sweetness is the qualitative content of certain sensory experiences that we then attribute as a property of what’s being tasted (see page 367 for his discussion of content).
 Dan says (my emphasis) “The manifest image…is an extremely sophisticated system of helpful metaphorical renderings of the underlying reality uncovered by the scientific image.” (366) But note that the scientific image is indeed an image, a model, a representation of reality, one that deploys representations such as concepts and numbers that may themselves not be locatable in the world as thus represented.
 The representations are qualitative in this instance, but the same applies to concepts and numbers: they aren’t locatable in the world they represent; see note 7.
 I’m tempted to dub this a basic rule of representation: we won’t find in the represented world those representational elements in terms of which that world is represented.
 On page 224 Dan says “… not only are colors real, but also consciousness, free will, and dollars.” But if consciousness and its contents are a user-illusion, then it seems colors exist in a kind of second-class reality. So we can perhaps construe Dan as arguing for a kind of reality hierarchy: the really real (the scientific image), and the conventionally, subjectively real (the manifest image).