What do we have access to?

Indirect realism and idealism are not popular with contemporary academic philosophers (in the 2022 PhilPapers survey, only 6.6% endorsed idealism and only 5.0% sense data theory), and to many — including me — they are profoundly unattractive.

Yet they retain some popularity among a wider public. When discussing philosophy of mind on social media, I frequently find people asserting as an unquestionable truth that the only things we are directly aware of are our own experiences and that all our beliefs about the external world are inferences from beliefs about our experiences. (My response is usually to ask (a) Who or what does ‘we’ refer to in this context? and (b) How do we gain direct access to our experiences? The only answers that work in the context are ‘a soul’ and ‘magic’, or some more nuanced variants of them.)

Why is this? I don’t know (the philosophical arguments are certainly not compelling), and I’d be interested to know what others think. But I suspect that one factor may be the way neuroscientists write about consciousness. They tend to stress that the brain has no direct access to the world it represents. Here’s an example from David Eagelman:

Here’s the key: the brain has no access to the world outside. Sealed within the dark, silent chamber of your skull, your brain has never directly experienced the external world, and it never will … Everything you experience — every sight, sound, smell — rather than being a direct experience, is an electrochemical rendition in a dark theater.

David Eagleman, The Brain: Story of You (Pantheon, 2017), p. 41

Now, I’m not suggesting that Eagleman or others who write like this endorse indirect realism. They are, I take it, making two perfectly good points: first, which aspects of the world we experience and how we experience them are determined by processes in our brains, which (let us suppose) create internal models of the environment, and, second, the brain has to construct its models from completely uninterpreted data — essentially, spiking patterns in neurons.

But such talk can easily be misinterpreted. A reader might reason as follows: ‘Scientists tell me that my brain doesn’t have access to the world outside. But I have access to something — this rich buzzing, booming world of sensory qualities. So this something must be an internal world, the model constructed by my brain. That’s what I’m directly aware of, and all my beliefs about the outer world are inferences from beliefs about this inner world.’

This is, of course, fallacious. My brain may not have access to the world beyond the skull, but it doesn’t follow that I, the whole organism, do not. The brain’s job (or one of its jobs) is to put the organism to which it belongs into a relation of tight sensitivity to the world around it — the relation we call ‘awareness’ or ‘experience’ — and the models the brain constructs are part of the subpersonal machinery that creates this personal relation.

Of course, our personal awareness of the world is not immediate and perfect; far from it. It is dependent on the hugely complex processes neuroscientists describe, and it is simplified, distorted, and caricatured in ways that reflect our needs as evolved biological organisms. But it is an awareness of the world, not of some inner simulacrum of it.

Indeed, if we were personally aware of an internal model of the world, then, from an explanatory point of view, we’d be back to square one. Neuroscientists would point out that the brain has no direct access to the models created in other brain regions and that it must construct our awareness of them from uninterpreted neural signals — making models of models. Drawing the same fallacious inference, indirect realism would become doubly indirect, then triply, and so on.

A dilemma for illusionists — and another for realists!

David Chalmers often — rightly — presses me to clarify exactly what it is that I and other illusionists deny. We say that we deny the existence of phenomenal properties, or qualia, but what exactly do we mean by this? Here, it seems, we illusionists face a dilemma. Is the notion of a phenomenal property a theoretical one or an observational one?

Suppose we say that the notion is a theoretical one — say, that of a property of experience that is nonphysical, not publicly observable, and immediately known. Then phenomenal realists such as Chalmers will say that that’s not what they mean by a phenomenal property. They mean simply the feel of experience — what it’s like. They do not define these feels as having features such as non-physicality, though they have arguments for thinking that they do in fact have them. Thus, if illusionists take this option, they are not denying the existence of properties realists believe in, but merely denying that those properties have the features many realists believe they have. Chalmers will be more than happy to engage with them on the latter point.

Suppose, then, that illusionists say that the concept of phenomenality is an observational one — the concept of the kind of feature people detect when they introspectively detect that they are having an experience of some kind. Then illusionists are denying something realists believe in, but also, it seems, making the absurd claim that experiences have no introspectively detectable aspect — that you detect nothing when you detect that you’re in pain!

This is the dilemma facing the illusionist. Francois Kammerer has likened it to the task Odysseus faced in navigating his ship between the two sea monsters Scylla and Charybdis. (See his talk ‘Defining consciousness and denying its existence’ at a workshop in Bochum.) What should the illusionist do?

The short answer is that they should reject the dichotomy and point out that all observation, including introspection, is theory-laden and that the concepts we employ in introspection are themselves infused with theoretical commitments. This is the line Kammerer takes, and I think it’s right. I won’t develop the response here, however. (I discuss the issue at much more length in a new paper forthcoming in a special issue of the French journal Klēsis, edited by François Loth.) Instead, I want to point out that illusionists can pose a parallel dilemma for the realist.

Here’s how they can do it. First, they need to sketch some positive account of what consciousness is, couched entirely in terms of informational and reactive processes centred on the brain. For present purposes, the details do not matter; the crucial thing is that the account is framed entirely in functional terms. The realist will say that the account omits, or at least fails to explain, something — the central phenomenal aspect of experience. (Note that it does not matter whether the proposed account is actually true; the point is that the realist will claim to know a priori that it is not true, or at least not fully explanatory, since it misses out something crucial.) Now comes the dilemma. How do realists conceive of the missing properties?

Suppose they conceive of them in the observational way, as the properties people detect when they introspectively detect that they are having experiences, with no commitment whatsoever as to the nature of these properties. This option was unattractive to illusionists, but it is awkward for realists too. How can they know that the detected properties are omitted from, or not explained by, the illusionist’s account? Why should they even suspect that they are not included? After all, they claim to have no idea what the properties are.

Suppose, then, that realists allow that the notion of phenomenality does have a theoretical component after all, and that they conceive of phenomenal properties as having certain specific features. Then they can maintain that the illusionist account is inadequate, on the grounds that it omits or fails to explain properties with those features. But if they make this move, then illusionists can deny the existence of phenomenal properties without denying that experiences have an introspectively detectable aspect. For they can say that experiences have an introspectively detectable aspect but this aspect is not phenomenal. What you detect when you detect that you are in pain is not really a phenomenal property.

Sauce for the goose is sauce for the gander!

Where does this leave us? It leaves us having identified the core questions as, first, what theoretical commitments are packed into the notion of phenomenality, and second, whether experiences have phenomenal properties as characterized by those commitments.

In response to the first question, I’m inclined to say that the key commitments are to phenomenal properties being (a) not characterizable in functional terms and (b) clearly revealed to introspection. Other claims, such as that phenomenal properties are non-physical, resist scientific explanation, and are radically private, derive from those core ones. I discuss this more in the Klēsis article.

As for the second question, I answer in the negative, of course.

Updated 3/12/22

Like a rainbow

Do illusionists deny the reality of consciousness? I’ve been discussing this on Twitter recently (see this thread, among others), and it has promoted me to try to think of analogies that might illuminate the illusionist perspective.

Here’s one: rainbows. Rainbows are real, aren’t they? You can see them with your own eyes — though you have to be in the right position, with the sun behind you. You can point them out to other people — provided they take up a similar position to you. Heck, you can even photograph them.

But what exactly is it that’s real? It seems as if there’s an actual gauzy, multi-coloured arc stretching across the sky and curving down to meet the ground at a point to which you could walk. Our ancestors may have thought rainbows were like that. We know better, of course. There’s no real coloured arc up there. Nor are there any specific physical features arranged arcwise — the rainbow’s “atmospheric correlates”, as it were. There are just water droplets evenly distributed throughout the air and reflecting sunlight in such a way that from your vantage point there appears to be a multi-coloured arc.

To sum up:

  • Rainbows, whatever they are: real
  • Coloured, spatially located aerial arcs: illusory
  • Experiences as of coloured, spatially located aerial arcs: real
  • Atmospheric conditions that cause experiences as of multi-coloured, spatially located aerial arcs: real

That’s very much how illusionists think of consciousness. It’s real enough. It’s the condition you’re in when you attend to things perceptually. I have it; you have it, scientists can study it. But, like a rainbow, it’s not what we naively take it to be.

When I reflect on my own experience, it seems to me that my consciousness is an inner world, where the world around me is rendered in private mental qualities — “qualia” — for my benefit alone. But there isn’t such a world. Neuroscience finds nothing like it in the brain, nor even anything isomorphic to it. Rather, it finds complex trains of neural activity proceeding in parallel and triggering a host of reactions — physiological, psychological, and behavioural. My sense of having a rich qualia-filled inner world is an impression created by all these processes, but the processes themselves are as different from the supposed inner world as a moisture-infused mass of air is from a colourful aerial arc.

To sum up:

  • Consciousness, whatever it is: real
  • A private qualia-filled mental world: illusory
  • The impression of a private qualia-filled mental world: real
  • Brain processes that produce the impression of a private qualia-filled mental world: real

I know what you are going to say! You’re going to ask about that impression of a private qualia world. What’s that exactly? Isn’t it a conscious experience — like the experience of seeing a rainbow — which itself belongs to a private qualia-filled mental world? If so, the whole idea is circular. I seem to be saying that the qualia world exists only in another qualia world. Does that second qualia world exist only in a third one, then, and so on? Ridiculous!

If illusionists thought like that, then their view would indeed be ridiculous. But they don’t. They don’t think that experiences exist in qualia worlds at all. They offer alternative accounts of what experiences are that don’t mention qualia. On the view I favour, experiences are complex sets of perceptually triggered psychological reactions and reactive dispositions. To have an experience as of a colourful arc in the sky is to form beliefs, memories, emotions, and a host of other reactive dispositions appropriate to the presence of such an arc. It is to be, as it were, in “sensing sky arc mode”. Similarly, to be under the impression that one has an inner qualia world is to react psychologically as if one had an inner qualia world — to think, talk, and react in countless other way as if such a world existed. That suggestion needs a lot of fleshing out, of course, and you might think it won’t work, but at least it shows that illusionists aren’t making a ridiculously circular claim.

That’s the analogy then. Consciousness is as real as a rainbow. It exists, but it is not a private qualia world, any more than a rainbow is a physical arc in the sky. So trying to find the neural correlates of the qualia world is as sensible as trying to find an arc-shaped structure in the atmosphere after a rain shower. And searching for a solution to the Hard Problem is like looking for the pot of gold at the end of a rainbow!

PS. After posting this piece, I was delighted to find that Daniel Dennett gave it his stamp of approval:

The Rolling Stones - She's A Rainbow (Official Lyric Video)

Do you know what sensations you’re having?

Last week, Matt Lieberman posted the video below on Twitter. (I believe it was originally posted on TikTok by the dancer featured in it.) The video illustrates change blindness. Large visual changes occur during the course of the video, which the viewer typically doesn’t notice. You may like to watch the video a few times and see if you notice the changes.

If you still haven’t noticed the changes, I’ll tell you. [Spoiler follows]

. . .

The colours of the dancers’ tops change markedly during the video. You can see the difference easily by jumping to different points in the video and noting the colours of the tops at each point.

You may be surprised that you missed such a large change, but it is not really surprising. Our visual systems are designed to keep track of things through changes in their appearance. Imagine you’re in a forest with a tiger stalking you. As the tiger moves in and out of the shade, the light reflected from its coat changes continually, but you need to ignore these changes and focus on what’s constant: the individual animal moving through the trees. And that is exactly what your brain does. In the case of the video, your brain accurately tracked the individual dancers, not confusing one with another, and it ignored changes in colour that were irrelevant to this task. Looked at in this way, change blindness is not a bug in our visual system but a feature, and we should expect it to occur all the time.

But this feature of vision presents a problem for a certain view of consciousness, which I’ll call the three-stage view. The view goes like this. Conscious perception proceeds in three stages. First, physical stimuli impact on our sense organs and produce neural activity in sensory processing regions of our brains. Second, this neural activity produces a visual sensation — a private mental quality which makes it like something to perceive the stimuli. Third, the sensation in turn produces reactions appropriate to its nature (unpleasant sensations cause us to shun the things generating them, pleasant sensations cause us to seek them out, etc). We react as we do because of what our experiences are like.

Now, when the colours changed without your noticing it, what happened at each of the three stages? There were certainly changes at the first stage. The light rays hitting your retina changed, and, presumably, at least some of the activity in your visual cortex did, too. There were no changes at the third stage, however — or at least no major ones. Maybe there were subtle changes in your behavioural dispositions that could be detected under experimental conditions. (I don’t know if this has been investigated; it would be an interesting project.) But your reactions did not change in a way that was noticeable either to you or to a casual observer.

What about the second stage? Did your visual sensations change? Was there a change in what the experience was like for you?

If there wasn’t, and your sensations didn’t change until you reacted, then the three-stage view is undermined. For the view says that our reactions are produced by our sensations; we react as if there is something green in front of us because we are having a sensation of green. But if we don’t have a green sensation until we react, then the sensation can’t be playing this role. Indeed, it is not clear why we need sensations at all, since the reactions occur independently of them.

So a defender of the three-stage view must say that our sensations change before we react. They can then continue to claim that when we do react we are reacting to a change in our sensations, albeit after a delay.

But this has a strange consequence. It means that we can be mistaken about our own current sensations. At the mid-point of the video, you thought you were having the same colour sensations as at the start, but you were in fact having different ones. And does that even make sense? Your sensations are supposed to define how things seem to you, and while you may be wrong about what colour something is, you can’t be wrong what colour it seems to be.

That’s not all. If you can fail to notice your sensations changing, then maybe you could fail to notice them fading out altogether. Maybe your sensations faded out an hour ago, and you haven’t noticed yet. You’ve continued to react as if they hadn’t faded out, of course, but during the video you continued to react as if your colour sensations hadn’t changed. Maybe you’ve never had colour sensations at all. Maybe you’re just reacting as if you have them. How do you know? All you can be sure of is what you think about your sensations. Maybe sensations are a sort of illusion.

Zac’s disappearing nonconsciousness

Clive Wearing is a former musicologist and musician who has chronic amnesia, both anterograde and retrograde. He can’t form new memories or retrieve old ones. Although he is fully conscious, Clive lives trapped in a perpetual present, with no awareness of his own past (according to Wikipedia his episodic memory has a capacity of only 30 seconds). He continually feels that he has just emerged from a long period of unconsciousness, and in his diary he repeatedly affirms that he is now at last awake, scoring out earlier entries which affirmed the same and which now mean nothing to him:

8:31 AM: Now I am really, completely awake.
9:06 AM: Now I am perfectly, overwhelmingly awake.
9:34 AM: Now I am superlatively, actually awake.

Clive’s condition is a personal tragedy for him and his loved ones, but it is a also a fascinating psychological case study, and I want to take it as the basis for a philosophical thought experiment. I hope this does not suggest any disrespect to Clive or his family. I certainly intend none.

Clive suffers from what we might call disappearing consciousness. At every waking moment he is fully conscious, but those conscious moments rapidly pass into oblivion, and Clive’s conscious life has a brief temporal extension. We can imagine his memory span reducing further — to twenty seconds, ten, one, less — until his conscious life is the merest flicker in an otherwise dark existence.

I want to imagine someone who is the inverse of Clive — someone who suffers from disappearing nonconsciousness. Consider Zac. Zac has suffered an illness which has left him a zombie in the philosopher’s sense. His brain functions exactly as it did before, taking in the same range of sensory information and using it to produce responses just like those of a fully conscious person. He can give detailed reports on the world around him and his own bodily condition, noticing everything a fully conscious person would. However, his brain no longer produces any subjective experience — his mental states no longer have any phenomenal feel to them, no ‘what-it-is-likeness’. The inner light of phenomenal consciousness has gone out, and Zac experiences the world unconsciously. Given the standard way of thinking of consciousness, this should be at least conceivable.

There is a twist, however. Zac is not a complete zombie. Unlike other philosophical zombies, he is aware that he is not phenomenally conscious. So when he describes the visual scene before him, he adds that he isn’t really seeing it. He knows what the world is like, but his experience is not like anything. If zombies are conceivable, then a partial zombie like Zac should be, too. (I have borrowed the notion of a partial zombie from Allin Cottrell, who uses it to question the conceivability of zombies. See his excellent paper ‘Sniffing the Camembert’.)

Zac’s lack of phenomenal consciousness troubles him, and he repeatedly notes it in his diary. (He can write perfectly well, of course, and is aware of what he is writing, though the experience of writing is not like anything for him.)

8:31 AM: Now I am really, completely unconscious.

So Zac is unlike Clive in not being conscious. He is unlike Clive in another way, too. Whereas Clive’s brain fails to record memories of being conscious, Zac’s brain keeps fabricating them. When it forms episodic memories of scenes and events, it tags them as having been experienced in the normal way, just as they were before Zac’s illness. So although Zac experiences the world unconsciously, he remembers it has having been experienced consciously.

The upshot is that Zac suffers from the opposite delusion to Clive. Whereas Clive continually feels that he is waking up into consciousness and denies his past consciousness, so Zac continually feels that he losing consciousness and denies his past nonconsciousness:

8:31 AM: Now I am really, completely unconscious.
9:06 AM: Now I am totally, overwhelmingly unconscious.

9:34 AM: Now I am fully, actually unconscious.

And as the latency period between experience and memory shrinks, Zac’s sense of nonconsciousness shrinks too, until it is a mere flicker of darkness in an otherwise illuminated life.

What is the moral of this? The obvious one is that even if our experiences do have a subjective phenomenal feel to them, this feel may play little or no role in generating our sense of being conscious — of its being like something to be us. So maybe consciousness doesn’t have much to do with phenomenal feel after all.

Illusionism cover image

Front cover of Illusionism book

The cover image for my 2017 book Illusionism as a Theory of Consciousness is a painting of a rather flamboyant stage magician performing a variety of tricks simultaneously. I found the image on Wikimedia and thought it was an appropriate visual metaphor for the theory discussed in the book. But who was this magician? Wikimedia says only this about the image:

Zan Zig performing with rabbit and roses, including hat trick and levitation. Advertising poster for the magician (who seems to have left no other trace behind).

Could it be Julius Zancig? It seemed unlikely to me, given the description of Julius’s act, which he performed with his wife Anges. I put a message on my website asking if anyone could find out more.

In 2020, Jeff Miner (a former student of Kent Bach at SFSU, now working in tech) contacted me to say that he’d done some research on the image, which he has kindly given me permission to share. Jeff wrote:

I asked around and crowd-sourced a bit.

It looks as though he was a magician (possibly from the Cincinnati area) who named himself in such a way as to be confused with Zancig.

There’s a second lithograph of him at the LoC.

This response I got seems the most complete:

It was fairly common for second and third rank magicians to use names that resembled those of first-rank magicians (e.g. Hoodini, Howdini, Houdyni, etc.). The Zancigs, (Agnes and Julius) toured with a two-person telepathy (second sight) act. They didn’t do bunnies, doves and goldfish. It’s possible there was a fellow who called himself “Zan Zig” in hopes that people would think they were seeing the Zancigs.

Since the US Copyright Office is part of the Library of Congress, and since this lithograph was copyrighted, I expect the LOC got the name from the copyright registration. Librarians are pretty good about researching items in their collections, and the LOC librarians are some of the best in the world.

As to who “Zan Zig” might have been, at least on the Google-Indexed Web all hits on “Zan Zig” are to this picture (or the second lithograph also at the LOC showing a fellow who looks like the same guy doing four different illusions.) The fellow top left in that second lithograph is the standard stage version of Mephistopheles from Faust.

Doing a search in The New York Clipper and the New York Dramatic Mirror for the year 1899 might reveal more, or maybe not if this fellow was a local Cincinnati magician.

In a second email, Jeff forwarded further information from one of his correspondents:

There was a magician of this period named “Zanzic,” He was referred to in Leaves From Conjuror’s Scrapbooks, with this paragraph:

Another magician by the name of Robinson has been traveling in the Western States for the past few years, but is going under the professional name of Zanzic. Being a clever performer, it would seem he ought to have originated a more healthful-sounding name, which is “sick’led o’er with a pale cast of thought.”

There is quite a bit more about him in Jim Steinmeyer’s book The Glorious Deception, pages 135-138. The first paragraph there reads:

Zanzic was a tall, slender, dark-haired magician. His real name was Robertson or Brenner, and he also worked under the name Henry Andre. Zanzic had been born in New Orleans, the son of a Creole fortune-teller. He was six years younger than Will [Robinson], an old friend from the days when they were both starting out in magic and used to meet at Martinka’s shop. His associates thought of Zanzic as unstable: accident-prone and filled with half-baked schemes. He certainly had the skill to be a good magician. But for Zanzic, the adrenaline of a performance was like a strange, addictive sort of poison that made him giddy and stupid.

In short, the illustration is of a hyperactive magician who was hoping to deceive people about his very identity. I think that makes it even more appropriate for a book about the addictive self-illusions our brains create.

Introducing jekylls

Philosophers of mind talk a lot about zombies. I want to introduce a related species of philosophical monster, which I shall call jekylls. Like zombies, jekylls are atom-for-atom duplicates of us, inhabiting a world with the same physical laws as ours — a world which, let’s assume, is causally closed. Your jekyll twin has all the same physical and functional states you do, including mental ones. It has the same functionally defined perceptions, sensations, thoughts, desires, memories, and emotions, and it is conscious in a functional way too. It also has a sense of self, built of memories, emotions, and introspective and interoceptive states — all functionally defined. (For simplicity, I’ll use ‘psychological’ as David Chalmers does in TCM to mean ‘psychological in a functional sense’.)

So far, then, jekylls are just like zombies. There is a difference, however. Jekylls also have phenomenal states, understood as qualitative mental states that can’t be characterized in functional terms. The phenomenal lights are on inside, as they supposedly are in us. But jekylls aren’t just like us, either. For their phenomenal states are not aligned with their psychological ones. There is a deep incongruity between what they are thinking and feeling psychologically and what they are thinking and feeling phenomenally. When they are psychologically calm, they are filled with phenomenal rage, when they are in psychological pain, they feel phenomenal bliss, when they are psychologically confused, they experience phenomenal clarity, and so on. They are phenomenal/psychological self-inverts.

As a consequence, jekylls have dual selves (you see now why I chose the name). As psychological beings, they have no introspective access to their body’s phenomenal states (which have no distinctive effects), and their phenomenal states make no contribution to their psychological sense of who they are. The subject of their phenomenal states — whatever it is — is completely isolated from the self manifested in their reactions, overt and covert. Each jekyll harbours a phenomenal Mr Hyde. (As with zombies, the literary parallel is not exact, since jekylls never morph into hydes; their inner hyde is forever locked away in a metaphysical limbo.)

Are jekylls conceivable? If zombies conceivable, then jekylls are too. We can conceive of zombies because there is no conceptual connection between functional facts and phenomenal facts. And if there no conceptual connection between functional facts and phenomenal facts, then jekylls are conceivable too. If you think that jekylls are not conceivable, then you have a conception of the phenomenal that is not the one employed in the zombie argument.

Now if phenomenal realism is true, then we are like jekylls, except that our phenomenal selves are beautifully aligned with our psychological ones. You, too, have an ineffective hidden self, but it perfectly mirrors the worldly self manifest in your reactions.

But wait a minute! How do you know that aren’t a jeykll — that you don’t harbour an inner hyde? If you are sure you don’t, then there are two explanations. The first is that you identify with your phenomenal self rather than your psychological one, and know that you are not a hyde. Your mind harmonizes perfectly with the psychological mind your brain processes implement. The downside of this option is that you are strangely alienated from the self manifest in your reactions. You are a phenomenal ghost ineffectively haunting a psychological machine. The other explanation is that at heart you identify with your psychological self and don’t really think you have a phenomenal self at all. You are a complex psychological being, and if you are tempted to think you have a phenomenal self as well, that’s due to features of your psychology. The downside of this is . . . you’re an illusionist!

‘Illusionism as a theory of consciousness’ translated into Spanish by David Vanegas

David A. Vanegas-Moreno has made a Spanish translation of my 2016 article ‘Illusionism as a theory of consciousness’ , which he has kindly allowed me to share here.

David is a psychologist and cognitive scientist from the Universidad de Antioquia, Colombia. His work has focused on the evolution of language and its role in human cognition. At the moment he is working on the “representation wars” in 4E cognitive science, and on the explanatory and integrative approach to cognitive science proposed by the new mechanical philosophy. He posts on Twitter as @evolanguagemind.

I am very grateful to David for his careful work in making my article accessible to Spanish-speaking readers. The translation is also available on my Publications pages.

The dynamical combination problem

Panpsychism is the idea that basic physical entities are essentially micro-consciousnesses and that our macro-consciousnesses result from combining the phenomenal natures of the physical entities that constitute us. The view faces the combination problem: how do simple, discrete micro-consciousnesses combine to produce complex, unified macro-consciousnesses? This problem has been much discussed, but there’s an aspect of it that has, I think, been relatively neglected. Here it is.

It looks like a sensible methodological assumption that if two entities are qualitatively identical from a physical point of view, then they are phenomenally identical too. If panpsychists don’t make this assumption, then it’s hard to see how they could construct anything like a science of consciousness. If panpsychism is true, then we are acquainted with only a tiny fraction of phenomenal reality — the portions that constitute our consciousnesses. The rest can be known only indirectly, by inference from corresponding physical features. But if phenomenal properties could vary independently of physical ones, then there would be no stable phenomenal-physical correspondences, and the bulk of phenomenal reality would not be even indirectly accessible to us. This could be case, but if it is, then there is no hope of explaining consciousness.

If the assumption is true, however, then it follows that there is very little phenomenal variation at the fundamental level. There are only a few types of fundamental particles, and all tokens of these types are qualitatively identical from a physical point of view, differentiated only by their spatio-temporal location. Every up-quark is physically identical to every other up-quark. So all tokens of each particle type are phenomenally identical too. (Differences in their spatio-temporal location are relational ones and cannot affect their intrinsic natures.)

It follows that fundamental phenomenal reality is quite uniform. There will just be a few different phenomenal ‘notes’ played billions upon billions of times. The combination problem is thus doubly difficult: the phenomenal elements from which our macro-consciousnesses are formed are not only simple but few in number, and we must explain how variety emerges from uniformity as well as how richness emerges from simplicity.

But this isn’t all. There is another aspect to the problem, which looks even more challenging. It’s a dynamical aspect. For if our assumption is sound, the phenomenal properties of the fundamental entities never alter. Fundamental particles do not change or age. So, except in exotic circumstances where particles are created or destroyed, the overall phenomenal soundscape stays the same, unaffected by particles’ changes in location (which, again, are irrelevant to their intrinsic natures). The fundamental phenomenal world is almost completely static. How, then, does a dynamical, ever-changing human consciousness emerge from a static phenomenal base? We might call this the dynamical combination problem.

Of course, all this assumes a rather old-fashioned picture of the microphysical world as one of discrete fundamental particles located in spacetime. The problem may look different, and perhaps more tractable, if we adopt a more sophisticated physics.

If you have any thoughts on this problem or any references to relevant discussions in the panpsychist literature, do please post them in the comments.

Essential-state materialism and multiple realizability

Suppose that phenomenal properties, such as the intrinsic feel of pain, are not physical properties in the standard sense. It’s a fair bet that science will be able to identify physical causes for all the effects of experience. So how can phenomenal properties have any effect on us? How does the feel of our experiences make a difference to us?

Panpsychists have a neat answer to this. They say that the phenomenal properties of experience are the intrinsic natures of the physical states that play the functional roles of the relevant experiences, including causing their characteristic effects. So (to use a hoary example) if the firing of C-fibres in the brain is the physical state that plays the functional role of pain, then the feel of pain is the intrinsic nature of C-fibre firing. Assuming this intrinsic nature does at least some of the causal work in producing pain effects, then it follows that the feel of pain is a cause of pain behaviour.

This view is, in effect, a radical form of type identity theory or central-state materialism. It says that pain is type identical, not with the brain state that plays the pain role, but with the essential nature of that brain state. We might call the view essential-state materialism.

And like type identity theory, the view faces an objection from multiple realization. The same functional role could be played by different physical states. This may actually happen in other creatures — octopuses, perhaps — and we can easily imagine it happening in us. The brain is highly plastic, and existing structures can be recruited to play new roles in response to damage. In the future, we may even be able to replace damaged brain structures with artificial ones that play the same role.

This poses an obvious problem for the essential-state view. If pain is the essential nature of C-fibre firing, then creatures who lack C-fibres cannot feel pain, even if they have functionally identical states and respond exactly as if they do feel pain. This is a counterintuitive, and possibly cruel, view. How do panpsychists respond?

It is implausible to say that all the physical states that could play the pain role have the same intrinsic nature. (And even if it weren’t, it wouldn’t solve the problem, since those states could also play other functional roles, with the result that pain could cause behaviour quite unrelated to pain, which is equally counterintuitive.) And of course panpsychists can’t say that the phenomenal nature of a physical state changes with the functional role it plays, since that would mean that a physical state’s phenomenal nature is not intrinsic to it.

I’d be grateful for any thoughts on this problem or for references to discussions of it in the panpsychist literature.

Introducing mephistos

Ich bin der Geist, der stets verneint!
— J. W. Goethe, Faust I, 1338

Zombies are not conscious but believe they are. They are as tempted as we are to believe that their experiences possess nonphysical qualitative properties, but they are wrong. I want to introduce another class of creatures, who are conscious but don’t believe they are. They are consciousness deniers. As a nod to the denying spirit depicted by Goethe, I’ll call them mephistos. Let me tell you a little about them.

Mephistos are conscious in just the way we are. Their brains are like ours and they inhabit a world like ours, with the same physical laws, the same psycho-physical laws (if there are any), and the same quiddities (if there are any). So if our experiences possess nonphysical qualitative properties, then theirs do too.

However, mephistos don’t conceptualize their consciousness in the way we do, as involving acquaintance with private mental qualities. Though every bit as reflective and self-aware as us, they don’t think of themselves as having a phenomenal inner world. If you ask them to describe what their experience is like, they tell you about the world, rhapsodizing about the vibrant red of ripe strawberries, the rich texture of velvet, the smokiness of dark roast coffee, and so on. They think of these as sensible qualities belonging to external objects or parts of their bodies, not as sensory qualities belonging to their minds.

Of course, mephistos know that their senses sometimes mislead them about the world. They dream and hallucinate and are subject to perceptual illusions just like us. But they don’t think of these episodes as demonstrating the existence of an internal world. When asked what happened, they just shrug and say that their senses lied. They thought they were aware of something, but they were wrong. They aren’t inclined to say that they really were aware of something mental.

If you point out that objects look different under different viewing conditions, mephistos generally deny it, either saying that their senses misled them or insisting that the objects in question didn’t look different at all. The tomato still looked red in the dim light, they say, just as a high tower still looks tall when seen from a great distance.

Mephisto philosophers and scientists do not think there is a hard problem of consciousness. Consciousness, they believe, is an immensely complex set of informational and control processes, all of which can, in principle, be reductively explained. Many have, however, argued that there is a hard problem of sensible qualities — the problem of explaining how surface textures give rise to colours, how molecules give rise to tastes, how pressure waves give rise to sounds, and so on. This problem has generated a lot of metaphysical speculation among mephisito scholars. (If you’re interested in their theories, have a look at this paper by the philosopher Alex Byrne, who has made a study of them.)

Today, however, a growing band of radical mephisto philosophers argue that this hard problem is misconceived. Sensible qualities, they argue, are illusory, and philosophers should turn aside from metaphysical speculation and focus on explaining how and why the brain produces the conviction that they exist.

So these are the mephistos. Their situation is just like ours, but they conceptualize it very differently. Is it we or they who are getting things wrong? And if there is any doubt, how can we be certain that the existence of phenomenal consciousness is a datum?

The last word about Mary

What happens when Mary leaves her black-and-white room and has a red colour experience for the first time? Here’s the answer, in outline. (I’ll assume for the sake of argument that Mary has developed the neural circuitry required for colour vision.)

  1. Mary’s visual system begins tracking something red, generating a huge set of active, interconnected first-order informational states, which in turn generate a vast range of reactions and reactive dispositions. Call complex of first-order informational and reactive states R1.
  2. Mary’s introspective system begins tracking the states in R1, generating a huge set of active, interconnected second-order informational states, which in turn generate a vast range of reactions and reactive dispositions. Call this complex of higher-order informational and reactive states R2.

  3. Mary has never instantiated R1 and R2 before and there was no practicable way to induce them in her pre-release.

  4. The informational states in R1 and R2 carry a mass of information about the world and about Mary’s current state.

  5. None of this information is about anything essentially private and non-physical (in the structure/dynamics sense). The informational states involved were generated by tracking physical features which could also be tracked by suitable scientific instruments and which were fully described in Mary’s textbooks.

  6. Mary’s total informational situation is novel. She has not previously instantiated this combination of active, interconnected informational states, and there was no practicable way she could have done so pre-release.

That’s it. (5) preserves physicalism, while (6) accounts for the intuition that Mary enters a new knowledge state. Fill in the details with your preferred theories of perception, introspection, and so on.

There’s no more to say ;)

Illusionism and compassion

I often get emails from people who have questions about illusionism. Most of them focus on the theory itself, but recently I received one that raised concerns about its emotional and ethical implications. The writer was persuaded that that illusionsm was true, but found it a deeply disturbing view, which, they felt, undermined the bases for empathy and compassion. Why should we care about other people and creatures if what’s happening in them is just a bunch of physical processes with no subjective component? Why should we even care about ourselves, if our subjective experience is an illusion? How, they asked, did I handle these implications of my view? Or were they not genuine implications after all? (That is a brief paraphrase the writer’s concerns, which were eloquently and feelingly expressed.)

Now, I don’t believe that illusionism has these that pessimistic consequences (just the opposite, in fact), but it worries me that some people think it does, and I plan to address these issues in my future work. For the moment, however, I will share my reply to my correspondent. Here is it, revised and edited a little.


I can see why you think that views like mine and Dennett’s might have negative consequences for the way we feel about other people and about ourselves. Many people share this concern, but I believe they are wrong, deeply wrong. I don’t think these negative consequences follow, and, in fact, I think that a materialistic perspective provides a much better foundation for value, empathy, and self-worth than the dualistic alternative. There’s a huge amount to say here, but let me sketch the outline.

The first point to make is that, like Dennett, I do not deny that we have conscious experiences, including bodily sensations of pain and pleasure, nor do I deny that these states matter morally. I just reject a certain theory of what conscious experiences are — the theory that says they involve acquaintance with private mental qualities or qualia. It’s qualia that I think are illusory, not consciousness itself.

Of course, some people think that qualia are essential to consciousness, and so I am denying consciousness in their sense. But to assume that their sense is the right one is to beg the question against my alternative. You can’t make a theory of consciousness true simply by defining consciousness as whatever your theory says it is! Science is continually correcting our naive theories of things.

So what is my alternative view? Roughly, it is that conscious experiences are complex informational-cum-reactive states: to have a conscious experience of something is to be receiving a stream of detailed sensory information about it and to be reacting to this information in a characteristic range of ways. So being in pain, say, doesn’t involve being acquainted with a private mental awfulness, but reacting in a host of negative ways to sensory information about the state of one’s body. The idea that our experiences have a private qualitative nature is a sort of illusion, which arises from the fact our brains monitor their own reactive processes and generate reactions to them in turn.

Here’s a recent article in which I try to explain this in a bit more detail: https://iai.tv/articles/the-demystification-of-consciousness-auid-1381

So why is pain bad? The short answer is that it’s bad because it signals that we are in a bad physical state — a state of sickness or injury — and because the reactions involved, both physiological and psychological, are of a negative, aversive kind. It’s a state we don’t like being in and that we want to stop being in.

I believe this account makes pain more real, more morally important, and easier to empathize with than the qualia one. Why do I say that? Because on the qualia view, pain is something that is wholly private and only contingently connected with pain reactions. We are all locked into private mental realities, and no one can ever really be sure what another person is feeling. That’s a view that seems to me scary and alienating.

A key point for me is that, even if they were real, qualia would only matter if they had effects on us. Pain qualia would only be a matter of moral concern if they produced pain reactions. If they didn’t, or if they produced other reactions instead, then why should we care about them? Suppose I am having intense pain qualia, but they are disconnected from the rest of my psychology and I’m sitting quietly, relaxing, sipping a drink, and assuring you that I feel absolutely fine. Should you be concerned for me? And what on earth could you do if you were? Any action you took would only affect my reactions, which are fine anyway. Can you even imagine the scenario? Can you separate out a pure essence of pain, distinct from all pain reactions, mental and physical? I can’t. Yet qualia realists have to say that scenarios like this are at least theoretically possible, since they hold that qualia are only contingently connected with reactions: it’s not what they do that matters, but what they are.

Look at it like this. Suppose I convince you that I don’t have qualia. And suppose you see me injure myself horribly. My stress levels soar, and I exhibit all the psychological and physiological signs of intense pain. I’m tensed up, grimacing, crying out, telling you that I feel terrible, and begging for assistance. What would you do? Would you help me, or would you ignore my pleas on the grounds that these are just physical reactions and I’m not experiencing the mental essence of pain? I’m sure you’d help. The point is that we don’t need to posit a hidden qualitative essence to justify empathy. The fact that someone is reacting negatively is enough. Pain is as pain does; it’s all there in our psychological and physiological engagement with the world, and it’s evident to anyone who cares to look. (The real cause for pessimism here is that too often people don’t care to look.)

In short, value is rooted in effects, not essences. Here’s a short piece by Daniel Dennett which uses the example of monetary value to drive home the point: https://ase.tufts.edu/cogstud/dennett/papers/consciousnessmoney.htm

The same goes for ourselves. We don’t need to have some non-physical essence — whether it be an immaterial soul or a private world of phenomenal properties — in order to have value and self-worth. Those things come from how we live and interact with the world and other people. We create value and self-worth through our engagement with the world around us and the people in it. It’s what do and how we react that matters, not some hidden essence.

So that’s roughly how I see it. I believe that the implications of illusionism are the opposite of the pessimistic ones some people see. As I see it, we aren’t sealed off from each other in private mental worlds, and our value doesn’t depend on mysterious essences. Everything that matters is out here in the open, in this wonderful physical world, and this is where we must seek meaning and value. I find this a comforting view. It means that that we are, in a sense, all one, part of the same world, and that — if we try hard enough — we can truly understand each other.

Consciousness is a life-transforming illusion

In 2015 I was invited to write a short piece on consciousness for the magazine Aeon. The text now appears to be unavailable on Aeon, so I am reposting it here.


From the moment we wake we are bombarded with stimuli. Electromagnetic radiation floods our eyes, pressure waves hit our ears, surfaces press against our skins, molecules adhere to the membranes of our noses and tongues. Our sense organs react, sending nerve impulses to our brains, where they trigger waves of neural activity, which may culminate in motor commands to our muscles (shielding our eyes from the light, for example). But something else happens, too. We have conscious experiences. We see a bright light, hear a scream, feel the roughness of a surface. There is something it is like to detect the stimuli; each experience has a distinctive qualitative aspect — a quale in philosopher’s jargon (plural qualia). Such experiences constitute what we call consciousness. But what is consciousness for? What do qualia do?

This may seem an odd question. The answer, surely, is that qualia carry information about the world. A red visual sensation tells us there is something red present; an acrid smell tells us something is burning; a pain tells us our body is damaged. There’s a problem, however. For we could get this information without qualia. Engineers build robots with computer vision systems that can detect and classify colours, shapes, and movements with considerable accuracy. They don’t need to give the robots qualia. Indeed, sometimes we behave in a robotic way ourselves. Most drivers have had the experience of driving absentmindedly, without paying attention to the road. Yet during these spells we must still be taking in visual information or we would crash. Or consider blindsight, a condition discovered in the 1970s by the psychologist Nicholas Humphrey. Humphrey studied a macaque monkey, Helen, whose primary visual cortex had been surgically removed. By the usual tests Helen was blind, but Humphrey discovered that, with encouragement, she could detect a range of visual stimuli, and in time she was able to interact with her surroundings almost as if fully sighted. (See a video of Helen and read Humphrey’s report.) Blindsight has been discovered in humans too, and the patients confirm that, though they can accurately ‘guess’ shapes and colours, they have no conscious visual sensations.

It appears, then, that the brain can do the work of perception without qualia. So, again, what is consciousness for? In his 2011 book Soul Dust, Humphrey proposes a novel idea. He argues that consciousness enriches life. It doesn’t add information; it adds interests and goals. Qualia are wonderful, magical things, and conscious creatures enjoy having them. They relish their sensations, and this relish gives them a deeper interest in their own existence. They also project qualia onto their surroundings and take a deeper interest in them too; and they come to think of themselves as having a self, which is of great importance to them. These developments, Humphrey argues, have great survival value and explain why evolution equipped with us consciousness. (Watch Humphrey talking about these ideas.)

This may be just the change of perspective we need to understand consciousness. There’s a catch, however. For qualia are very strange things; they are utterly unlike any properties known to the physical sciences, and many philosophers argue that they are nonphysical. But there is good reason to think that everything that happens in the physical world has a physical cause. Since we are part of the physical world, this means that if qualia are nonphysical, they cannot affect us. Humphrey’s proposal threatens to be self-defeating. Qualia enrich life because they are magical; yet because they are magical they can’t affect us and enrich life!

There’s a possible way out of this, which Humphrey himself adopts. It involves another radical idea. Maybe qualia are a sort of illusion. Evolution couldn’t set it up so that brain states really have qualia, so it did the next best thing. It set things up so that they seem to have qualia when we attend to them (when we introspect). Consciousness is, as Humphrey puts it, a sort of inner magic show, in which brain states are the actors and introspection the audience.

This is a big pill to swallow, and even if you’ve gone along with the argument so far you will probably want to get off here. An obvious objection is that, when it comes to qualia, seeming is reality. If I seem to be having a sensation of red, then I’m having one. This looks like a knock-down objection, but maybe we can edge round it. Here’s the idea.

Cognitive science sees the mind as a representational system, a system that records information about the world in a sort of internal code and uses this information to guide behaviour. On this view, for us to be aware of anything, our brains must represent it. This goes not only for external properties accessed through the senses (which can be represented in a robotic, blindsighted way), but also for internal properties accessed through introspection. Even if our brain states did have qualia, our brains would have to represent these qualia in order for us to be aware of them. Unrepresented qualia would be no more to us than unheard sounds. But representations are not always accurate — sometimes our brains misrepresent things. Indeed our surroundings might be set up precisely to induce such misrepresentation. A prankster might use scenery and video projections to trick a person into thinking they were seeing things they weren’t. And maybe evolution has pulled a similar trick on us — setting up our internal landscape so that introspection represents it as illuminated with magical, nonphysical qualia. Of course, it doesn’t seem that qualia are an illusion, but it wouldn’t if evolution has done its work well.

This is counterintuitive, but is it more so than the view that consciousness does nothing? It is very plausible to think that consciousness transforms the lives of the creatures who possess it, but maybe it is a transformation that can be wrought only by trickery.

Originally published in Aeon online magazine, 25 June 2015.

Nothing but

Many people find physicalism an inhumane, philistine view. I wish I could dispel that idea. What underlies it, I suspect, is the ‘nothing but’ thought: If we are nothing but matter, then where is our specialness, our value, our subjectivity?

But why does it matter what we are made of? Suppose we were immaterial souls instead of physical beings. Would that make us special? Why? Couldn’t we still worry that we were nothing but soul stuff?

So where does our specialness come from? Perhaps our physical bodies are infused with a nonphysical essence that confers subjectivity and value? But that suggestion explains nothing at all. It’s just saying that are special because we possess an intrinsic specialness.

I think there’s a better way of looking at it. It’s not the stuff we’re made of that matters, nor some essence within it. It’s the way the stuff is organized. Is Michelangelo’s David ‘nothing but marble’? Yes; there’s no extra ingredient or special essence. But it’s marble shaped in a meaningful way by the hands of a great creative artist. And we are matter shaped in a meaningful way by billions of years of natural experimentation and selection.

It’s this billion-year heritage of natural design that has endowed us with the sensitivities and reactive dispositions that underpin our sense of value and subjectivity. We’re matter that nature has made special — and we’re beginning to understand how nature did it.

The phenomenal concept strategy is a worn-out band-aid

For a quarter of a century, the default physicalist response to arguments for property dualism has been the phenomenal concept strategy (PCS). The strategy turns on a claim about the nature of our phenomenal concepts — the concepts we employ when we attend to our current experiences and think about what they are like. There are many variants of the strategy, and the literature on it is large and technical, but the core idea is simple.

It’s this. Phenomenal concepts function as bare referential devices — demonstratives perhaps. They do not pick out their referents as properties that fit some physical description but latch onto them directly via the exercise of some mental capacity. Since we do not conceptualize phenomenal properties as physical ones, we can easily imagine them varying independently of the physical facts, and this accounts for the intuitions that drive the anti-physicalist arguments — intuitions about zombies, inverts, Mary, and so on. Yet, phenomenal properties might be physical ones all the same. The only dualism the anti-physicalist arguments establish is one of concepts, physical and phenomenal.

I don’t think the strategy works. For it does nothing to explain why we find phenomenal properties anomalous. After all, we employ direct referential devices all the time without generating any ontological worries. Imagine being in a chemistry lab and asking, “What’s this?” or “What sort of stuff is that?”, pointing to a substance or holding up a sample. We don’t conceive of the substance we’re referring to in any particular way — as, let’s say, an acid salt. And, I suppose, we could imagine the substance being removed while all the acid salts remain where they are. But if we are told on good authority that the substance is an acid salt, then we are satisfied. We wouldn’t typically experience any puzzlement as how it could be an acid salt, and we wouldn’t think it conceivable that the stuff we’re indicating could disappear while all the acid salts remained in place. If we were to feel any puzzlement on these matters, it would because of how the stuff looked and our background beliefs about what acid salts are like.

If the PCS were sound, then the same should be true of phenomenal properties. Gesturing inwards at a twinge of pain and asking “What’s this?”, should not generate any intuitions about the nature of the state picked out and we should have no difficulty in accepting that it is a physical one, if that’s what the science indicated.

But that doesn’t happen. Even if we’re thoroughly convinced that the brain has no nonphysical properties, we still feel puzzled by the situation. We still can’t understand how this twinge of pain could be a brain state, and we still have a strong inclination to think that there’s some extra feature present that is only contingently connected to the physical.

The moral I draw from that is that phenomenal concepts are not bare referential devices. They incorporate some substantive conception of their referents. If they are demonstratives, they have a tacit theoretical sortal attached. We wonder, not simply, “What’s this?”, but “What’s this phenomenal feel?”.

What is this substantive conception of the phenomenal? I think it’s roughly the one Daniel Dennett dismantled in “Quining qualia” — the concept of a qualitative state that is private, ineffable, intrinsic, and immediately apprehended. Maybe those commitments are qualified in various ways, but they are still strong enough to make the conception incompatible with our conception of the physical. Hence our puzzlement.

If that’s right, then there’s only one option for the physicalist, and that is to say that phenomenal concepts misrepresent their referents. The properties they pick out (assuming they pick out determinate properties at all, which they may not) aren’t really phenomenal ones. And that’s illusionism.

For twenty-odd years, the PCS has acted as a band-aid holding physicalism and phenomenal realism together, and it’s worn out.

Accelerating research on consciousness?

Back in December, psychologist and author Christian Jarrett got in touch to ask what I thought about the new project “Accelerating Research on Consciousness” organised by the Templeton World Charity Foundation. See this news story for more information about the project. Christian incorporated some of my comments into an article for BBC Focus magazine (which I recommend) but I thought I’d post my full reply here, in case anyone is interested. Here it is.

I have mixed feelings about the project. I’m delighted to see more funding for experimental work on consciousness. The data collected will undoubtedly be useful. I have worries, however. It looks like the project will focus on explaining consciousness in the phenomenal sense. That is, the organizers and participants conceive of conscious states as essentially subjective ones, involving awareness of phenomenal properties or qualia (the private mental ‘feel’ or ‘what-it-likeness’ of experience). If that’s right, then I am dubious of the chances of making decisive progress.

To begin with, it’s hard to see how one could explain phenomenal properties in terms of brain processes. The two things are just too different. (This is the so-called ‘hard problem’ of consciousness.) The most we can hope to do is to find correlations between brain processes and phenomenal properties. And even then there’s a methodological problem. For there can be no objective test for the presence of essentially subjective properties. The best we can do is to test for objective indications of their presence, such as the subject’s reports and reactions. And this means that tests of correlation hypotheses can never be decisive. Suppose theory A says that conscious state C occurs when brain region N1 is active, whereas theory B says that N1 isn’t sufficient on its own and that brain region N2 needs to be active as well. And suppose we run some experiments and find that participants report C when both N1 and N2 are active but not when only N1 is. Does this prove that theory A is wrong and theory B right? No. It might be that N1 is sufficient for C, but that N2 is needed to enable us to report it. The same problem will arise if we try to test for nonverbal indications of C. Again, how do we tell which brain states are necessary for the conscious state itself and which are necessary for producing the behavioural indications of it? Since there is no way of directly testing for subjective properties, we can never definitively rule out any theory.

In short, so long as we focus on phenomenal consciousness, we’re never going to have decisive tests of our theories. The moral I draw is that shouldn’t focus on phenomenal consciousness. In fact, I believe that we do not have phenomenal consciousness; it’s a kind of introspective illusion, which reflects the limited access we have to our own mental processes. (I call this view ‘illusionism.’) The real task is to explain our intuitions about phenomenal consciousness — why we think we possess it.

As regards the theories currently being tested, I am very sceptical of IIT. It is intended as a theory of phenomenal consciousness, so the worries I’ve just mentioned apply, but even as theory of that, IIT is implausible. All kinds of things can have a rich informational structure in the relevant sense, so the theory has the consequence that inanimate objects can be phenomenally conscious. Even a blank wall could be.

I am much more sympathetic to Global Workspace theory, though I think it should be construed as a theory of access consciousness — of the awareness of information in a functional sense — rather than phenomenal consciousness. Moreover, it needs to be supplemented with some account of why we think we have phenomenal consciousness.

As for what I’d like to see next: Unsurprisingly, I’d like to see the project test illusionist theories of consciousness, which focus on explaining our intuitions about phenomenal consciousness. These do not face the problems I’ve mentioned, and they offer a promising line of research. It’s early days yet, but such theories are being developed. A good example is the Action Schema Theory proposed by the Princeton neuroscientist Michael Graziano and his colleagues.

The bottom line, then, is that the funding for experimental work is welcome and the data gathered will be useful, but the project is unlikely to settle anything until we have a better conception of exactly what it is we are trying to explain.

Bright shiny colours

What are colours? My view is that they are properties of surfaces in the world around us — albeit complex gerrymanded ones, which can be picked out only by reference to our reactions to them. Blue things are things that evoke a certain distinctive cluster of reactive dispositions in us. Note that that I do not say that they are ones that produce blue sensations in us. I don’t think that experiencing blue involves entertaining a mental version of blueness — a blue quale or phenomenal property.

Where then is the quality of blueness ? It’s not out there in the world. Out there there’s just a surface with a microstructure that reflects certain wavelengths of electromagnetic radiation. And I’ve denied that there is any blue quality in our minds. So where is the blueness of the blue?

My answer is that it is not really anywhere. It’s a property that our minds misrepresent external objects as having. However, it’s a property that corresponds to, and carries information about, something real and important — namely, the affordances of the objects in question. That needs a lot of unpacking and qualification, but the general idea is this. We are tuned up, by biological evolution, cultural evolution, and personal experience, to track worldly properties that it’s useful for us to notice. Such properties afford us opportunities for action in various ways; they have specific affordances. An object’s affordances are reflected in the suite of reactive dispositions its perception triggers in us — the suite of beliefs, expectations, associations, emotions, priming effects, and so on.

Now my suggestion is that the human brain monitors its own reactive dispositions and generates schematic representations of them, which are linked to its representations of the objects that triggered them. The upshot of this is that we experience the world as being metaphorically coloured by our reactions to it. We experience objects as having a distinctive but ineffable significance for us, which is a marker of their affordances. This is what we call their quality or feel. The blueness of blue is a distorted representation of the affordances it presents, represented as a property of the object itself.

That’s still very schematic, but a little example may help. Consider shiny, metallic colours, such as silver and gold. These seem to have a distinctive feel to them, and as a child I was very puzzled as to where they fitted into the visible spectrum. But, of course, they are not really different colours. Shiny things are just regularly coloured things whose brightness (and colour if they are very shiny) varies markedly with viewing angle. What gives them their distinctive ‘feel’ is precisely the affordances they present. We expect them to change in a distinctive way as we move in relation to them. The ‘feel’ of metallic colour just is the expectation of this effect.

A postscript: Another illustration of this is afforded by Gregory Thielker’s paintings of scenes though rain-spattered glass. In me, these create a powerful response (‘feel’, if you like). Doubtless, this is in part because they evoke memories of glum hours spent in traffic during rainy commutes. But I think it also reflects the way they trigger strong expectations that the scene will morph and distort in a distinctive way as the water drips or I move my head.

Illusion or identity?

Illusionists believe that consciousness involves no properties that are not detectable and fully describable by third-person science. Any other properties we think are involved are illusory. Suppose that’s right. Still, why should it follow that phenomenal properties are illusory? Why not say that they are properties that are detectable and fully describable by third-person science? It’s true (the objection continues) that we think of phenomenal properties as ones that present a problem for science — that pose a hard problem — but it doesn’t follow that they really do present one. Maybe we are just wrong about them.

Suppose that phenomenal concepts do in fact track completely unmysterious brain properties, which for some reason we mistakenly think of as nonphysical. There are many candidate explanations of why we might do this. If that’s the case (and illusionists don’t deny the possibility), then wouldn’t it be better to say that phenomenal properties are real but different from what we thought?

Here’s my answer. Maybe we could say that. It’s a revise-or-eliminate situation, and there is no simple procedure for determining the best way to go. But here are some reasons for rejecting the revisionary route.

First, it would invite confusion. The concept of the phenomenal carries a lot of connotations that physicalists must reject — assumptions about the reliability of introspection, intuitions about well-known thought experiments, associations with dualist notions such as sense data, and so on. Using a term with all this theoretical baggage is not the most perspicuous way of presenting a physicalist theory of consciousness.

Second, it would be misleading. The notion of phenomenal consciousness has become bound up with that of the hard problem — a problem that is supposed to be both substantive (there’s a real thing that needs explaining) and qualitatively different from ‘easy’ problems that can be solved by cognitive science. To offer a theory of phenomenal consciousness is to suggest that one has solved this hard problem, and physicalists shouldn’t do that. For physicalists, there is no hard problem, only the problem of explaining why there seems to be one.

Third, it would be tedious. In theoretical work, we’d have to laboriously disinfect phenomenal concepts before use, explicitly disavowing all their theoretical accretions.

Fourth, it would be pointless. After disinfection, we’d be left with nothing more than a bare demonstrative or quotational device, equivalent to ‘whatever this is’, applied introspectively. It’s not clear that this would pick out something determinate or theoretically interesting. We’d be gesturing at the whole complex perceptual-cum-reactive state triggered by the current stimulus, and without further specification it’s doubtful that the gesture would pick out a clear target for scientific investigation. (By contrast, gesturing at the supposed qualitative aspect of the state would narrow down the target, but only to something that physicalists must say is illusory.)

Fifth, it’s restricting. Physicalists need phenomenal concepts in their old theoretically laden senses in order to describe how people mistakenly think of consciousness (‘It seems that experiences have a phenomenal aspect as well as a functional one’). Compare the term ‘witch’. If we revise it to mean female naturopath, then it becomes harder to express what mediaeval people thought. After all, they were right to think that there were witches in that sense. Of course, this is only a linguistic problem and it could be solved by paraphrase, but it’s a consideration.

In the end, the concept of the phenomenal is too compromised to be useful to science. As Daniel Dennett says in his Consciousness Explained, let’s cut the tangled kite string and start over. Phenomenal properties are illusory.

Imagine

With apologies to John Lennon

Imagine there’re no qualia
It’s easy if you try
No feel or what-its-likeness
Just plain old cog sci

Imagine all the zombies
Being just like us

Imagine there’re no inverts
It isn’t hard to do
Nothing for Mary to learn
And no hard problem, too

Imagine all the people
Being illusionist

You may say I’m a quiner
But there’s nothing wrong with that
I hope someday you’ll join us
And learn what it’s like to be a bat.