The problem with the “hard problem”

Robert Lawrence Kuhn is well-known as the creator and host of the public television series Closer to Truth, an invaluable source of interviews with major contributors to a variety of contemporary debates in philosophy, theology, and science.  (Longtime readers will recall an exchange Kuhn and I had at First Things some years back on the question of why there is something rather than nothing, which you can find here, here, and here.)  Recently, Kuhn’s article “A landscape of consciousness: Toward a taxonomy of explanations and implications”    appeared in the journal Progress in Biophysics and Molecular Biology.  It is an impressively exhaustive survey of the field, and will be extremely helpful to anyone looking for guidance through its enormous and often bewildering literature.  Kuhn kindly includes a section on my own contributions to the subject.

The “hard problem”

Whether by design or not, the article marks the thirtieth anniversary since David Chalmers introduced the phrase “hard problem of consciousness” to label what has in recent analytic philosophy of mind become a focus of obsessive attention.  Introducing the problem, Kuhn notes:

Key indeed are qualia, our internal, phenomenological, felt experience – the sight of your newborn daughter, bundled up; the sound of Mahler's Second Symphony, fifth movement, choral finale; the smell of garlic, cooking in olive oil.  Qualia – the felt qualities of inner experience – are the crux of the mind-body problem.

Chalmers describes qualia as “the raw sensations of experience.”  He says, “I see colors – reds, greens, blues – and they feel a certain way to me.  I see a red rose; I hear a clarinet; I smell mothballs.  All of these feel a certain way to me.  You must experience them to know what they're like.  You could provide a perfect, complete map of my brain [down to elementary particles] – what's going on when I see, hear, smell – but if I haven't seen, heard, smelled for myself, that brain map is not going to tell me about the quality of seeing red, hearing a clarinet, smelling mothballs.  You must experience it.”

Those last two sentences indicate why qualia are regarded by so many contemporary philosophers as problematic.  The problem has to do with the metaphysical gap that seems to exist between physical facts on the one hand (including facts about the brain) and facts about conscious experience on the other (especially facts about qualia).

The nature and reality of this gap has been spelled out in various ways.  Consider Chalmers’ famous “zombie argument.”  It is possible at least in principle, he says, for there to be a world physically identical to our own down to the last particle, but where there are none of the qualia of conscious experience.  Thus, in this imagined world, there are creatures who are not only anatomically but also behaviorally identical to us, in that they speak and act exactly as we do in response to the same stimuli.  But they possess no inner life of the kind characterized by qualia.  They are “zombies” in the technical sense familiar to readers of contemporary work in the philosophy of mind (a sense very different from that familiar from Night of the Living Dead and similar movies).  But if they can be physically identical without possessing qualia, then the facts about qualia must be something over and above the physical facts.

A related argument known as the “knowledge argument” was famously put forward by Frank Jackson.  Imagine Mary, a scientist of the future who, for whatever reason, has spent her entire life in a black and white room, never having experiences of colors.  She has, nevertheless, through her studies come to learn all the physical facts there are to know about the physics and physiology of color perception.  For example, she knows down to the last detail what is going on in the surface of a red apple, and in the eyes and nervous system, when someone sees the apple.  Suppose she leaves the room and finally comes to learn for herself what it is like to see red.  In other words, she comes for the first time to have the qualia associated with the conscious experience of seeing a red apple.  Surely she has learned something new.  But since, by hypothesis, she already knew all the physical facts there were to know about the situation, her new knowledge of the qualia in question must be knowledge of something over and above the physical facts.

As you might expect, the lesson many draw from these arguments is that materialism, which holds that the physical facts are all the facts there are, is false.  And this is taken to show in turn that consciousness will never be explicable in neuroscientific terms.  But while this certainly makes qualia a problem for the materialist, you might wonder why they would be a problem for anyone else.  Can’t the dualist happily take these implications to be, not a problem, but rather a confirmation of his position?  But it’s not that simple.  For arguments like the zombie argument also seem to imply that qualia are epiphenomenal, having no causal influence on the physical world.  And if qualia have no causal influence on anything we do or say, how are we even talking about them?  Indeed, how can we know they are really there?

How to resolve such puzzles, and determining whether it is materialism, dualism, or some alternative view that will survive when they are resolved, is what the “hard problem” is all about.  An enormous amount of ink has been spilled on it in recent decades, as Kuhn’s article shows.  Now, philosophical work can often be of great value even when it is based on erroneous presuppositions, because it can teach us about the logical relationships between certain concepts, and the consequences of following out consistently certain philosophical assumptions.  That is why it will always be important for philosophers to study thinkers of genius who got things badly wrong (which would in my view include Heraclitus, Parmenides, Zeno, Ockham, Descartes, Spinoza, Leibniz, Berkeley, Hume, Kant, and many others).

In my opinion, the literature on the hard problem is of value in just this way.  We learn from it important things about the relationships between key philosophical ideas, such as the conceptions of matter and of consciousness that have dominated modern philosophy.  And it shows us, in my view, that materialism is false, since the conception of matter the materialist operates with rules out any materialist explanation of consciousness, and denying the existence of consciousness in order to get around this problem would be incoherent.  This literature also illuminates the problem that post-Cartesian forms of dualism have in explaining the tight integration between mind and body that everyday experience reveals to us to be real.

Origin of the problem

All the same, the so called “hard problem” is, in my view, a pseudo-problem that rests on a set of mistakes.  There is a reason why ancient and medieval philosophy knew nothing of the “mind-body problem” as modern philosophers conceive of it, and nothing of the so-called “hard problem of consciousness” in particular.  And it’s not because they somehow overlooked some obvious features of mind and matter that make their relationship problematic.  It’s because the problem only arises if one makes certain assumptions about the nature of mind and/or matter that ancient and medieval philosophers generally did not make, but modern philosophers often do make. 

Points like the ones to follow have often been made not only by Aristotelian-Thomistic philosophers like me but also by Wittgensteinians like Peter Hacker and Maxwell Bennett and Heideggerians like Frederick Olafson.  The key moves that generated the so-called mind-body problem can be found in Descartes, so that Thomists, Wittgensteinians, Heideggerians, and others commonly characterize them as “Cartesian.”  But variations on these moves are found in early modern thinkers more generally. 

On the side of the body, modern philosophy introduced a conception of matter that is essentially reductionist and mathematicized.  It is reductionist insofar as it essentially takes everyday material objects to be aggregates of microscopic particles.  A stone, an apple, a tree, a dog, a human body – all of these things are, on this view, really “nothing but” collections of particles of the same type, so that the differences between the everyday objects are as superficial as the differences between sandcastles of diverse shapes.  The new conception of matter is mathematicized insofar as it holds that the only properties of the microscopic particles are those that can be given a mathematical characterization.  This would include size, shape, position in space, movement through space, and the like, which came to be called the “primary qualities” of matter. 

With color, sound, heat, cold, and other so-called “secondary qualities,” the idea was that there is nothing in matter itself that corresponds to the way we experience them.  For example, there is nothing in an apple that in any way resembles the red we see, and nothing in ice water that in any way resembles the cold we feel.  The redness and coldness exist only in our experience of the apple and the water, in something like the way the redness we see when looking through red-tinted glasses exists only in the glasses rather than in the objects we see through them.  Physical objects, on this conception, are nothing more than collections of colorless, soundless, odorless, tasteless particles.  This includes the brain, which is as devoid of these qualities as apples and water are.

On the side of the mind, meanwhile, the modern picture makes of it the repository of these qualities that are said not truly to exist in matter.  Redness, coldness, and the like, are on this view not the qualities of physical things, but rather of our conscious experiences of physical things.  They are the “qualia” of experience.  Often associated with this view is an indirect realist theory of perception, according to which the immediate objects of perception are not physical objects themselves, but only mental representations of such objects.  For example, when you see an apple, the immediate object of your perception is not the apple outside you, but rather an inner representation of it.  The situation is analogous to looking at someone who is ringing your doorbell through a security camera that is generating an image of the person on a computer screen.  What you are directly looking at is the screen rather than the person, and the colors you see on the screen are strictly speaking features of the screen rather than the person (even if they are caused by something really there in the person). 

On the indirect realist theory of perception, conscious experience is experience of the inner “screen” of the mind itself rather than of the physical world.  The physical world is the cause of what we see on this inner screen, just as the person ringing your doorbell is the cause of what you see on your computer.  But we have no direct access to it, and can know it only by inference from what we see on the inner screen.  Our awareness of the screen involves something called “introspection,” which is analogous to perception except that its objects are purely mental and known directly, whereas the objects of perception are physical and known indirectly.  For example, by introspection you directly know your experience of the apple and the reddish, sweet, fragrant, etc. qualia of this experience.  Perception involves indirect knowledge of an external physical object that is the cause of your having this experience and those qualia.

The mind as conceived of on this picture is often called the “Cartesian theater.”  The reductionist-cum-mathematicized conception of the physical world I described is often called the “mechanical world picture.”  The modern mind-body problem is essentially the problem of determining how these two pictures are related to one another, which is why no such problem existed in ancient and medieval philosophy (or at least not in its mainstreams, though the ancient atomist Democritus noted a paradox facing his own position that is at least in the ballpark).

The problem is that, on the one hand, since the Cartesian theater is characterized by properties that the mechanical world picture entirely extrudes from the material world, that theater itself cannot be part of the material world.  Thus are we left with Cartesian dualism or something in its ballpark.  But on the other hand, the separation between them is so radical that it becomes utterly mysterious how the Cartesian theater can get into any sort of epistemic or causal contact with the mechanistically described material world.  Thus are we left with skepticism and with the interaction problem or something in its ballpark.

The “hard problem of consciousness” is just the latest riff on this post-Cartesian problematic.  On the one hand, it is said, neuroscience can shed light on the relatively “easy problems” about how neural processes mediate between sensory input and bodily behavior, but not on the “hard problem” of why any of this processing is associated with qualia.  On the other hand, it is said, it is hard to see how qualia could be other than epiphenomenal given the “causal closure of the physical.”  The former point recapitulates traditional Cartesian arguments against materialism and the latter recapitulates the interaction problem the materialist traditionally raises against the Cartesian.

Dissolution of the problem

From the point of view of Aristotelians, Wittgensteinians, Heideggerians and others, what is needed is, not further efforts to try to find a way to stop this merry-go-round, but rather not to get on it in the first place.  In particular, we need to abandon the background modern philosophical assumptions that generate the “hard problem of consciousness” and other variations on the mind-body problem.  For instance, we need to reject the reductionist-cum-mathematicized conception of the material world we’ve inherited from early modern philosophy’s mechanical world picture.  With natural substances, it is simply a mistake to think of them as no more than the sum of their parts, and to suppose that to understand them involves determining how their higher-level features arise out of lower-level features in a strictly bottom-up way.

In the case of a human being or non-human animal, it is a mistake to look for consciousness at the level of the particles of which the body is made, or at the level of nerve cells, or even at the level of the brain as a whole.  Consciousness is a property of the organism as a whole.  The mathematicized description of matter that the physicist gives us, and the neural description the physiologist gives us, are abstractions from the organism as a whole, useful for certain purposes but in no way capturing the entirety of the organism, any more than a blueprint captures all there is to a home.  We should no more expect to find consciousness at the level of physics or neuroscience than we should expect to find Sunday dinner, movie night, or other aspects of everyday home life in the blueprint of a house.

We should also reject the assumptions about perception and introspection inherited from post-Cartesian philosophy of mind.  As Bennett and Hacker show in detail in their book Philosophical Foundations of Neuroscience and elsewhere, discussions of the hard problem of consciousness routinely characterize the relevant phenomena in ways that are not only tendentious, but bizarre from the point of view of common sense no less than of Aristotelian and Wittgensteinian philosophy. 

For example, consider Chalmers’ remark, quoted above, that seeing a red rose, hearing a clarinet, and smelling mothballs all “feel a certain way.”  It is common in the literature on qualia and consciousness to see claims like this.  The idea seems to be that different kinds of conscious experience are differentiated from one another insofar as each has a unique “feel” to it.  But this is not the way people normally talk.  Suppose you asked the average person what it feels like to see a red rose, hear a clarinet, or smell mothballs.  He might suppose that what you had in mind was whether these perceptions evoked certain emotions or memories or the like.  For example, he might imagine that what you are wondering about is whether seeing the rose evokes a feeling of longing for a girlfriend to whom you once gave such a rose, or whether hearing the clarinet evokes happy memories of first hearing a Benny Goodman record, or whether smelling mothballs generates a feeling of nausea. 

Suppose you said to him “No, I don’t mean anything like that.  I mean, what is the feel that the experience of seeing red has even apart from that sort of thing, and how does it differ from the feel that the experience of hearing a clarinet has?”  He would likely not know what you are talking about.  In the ordinary sense of the word “feel,” it doesn’t “feel like” anything to see a red rose or hear a clarinet.  Seeing an object is one thing, hearing a clarinet played is another, and “feeling” something (like an emotion) is yet another thing, and not at all like the first two.  Discussions of qualia routinely take for granted that there must be some special “feeling” that demarcates one experience from another.  But as Bennett and Hacker note, that is not how we ordinarily do in fact distinguish one experience from another.  Instead, we distinguish them by reference to the object of the experience (a rose versus a clarinet, say) or the modality of the experience (seeing as opposed to hearing).  There is no “feel” on top of that that plays a role in distinguishing one experience from another.

Similarly, it is often said that each experience has a distinct “qualitative character” to it.  There is, we are told, a “qualitative character” to an experience of seeing one’s newborn daughter that is different from the “qualitative character” of an experience of smelling garlic cooking in olive oil.  But as Bennett and Hacker point out, this too is an odd way of speaking, and certainly not what the ordinary speaker would say.  To be sure, seeing one’s newborn daughter may cause one to feel affectionate, and smelling garlic cooking in olive oil may make one hungry.  In that sense there is a different feel or qualitative character to the experiences.  But all this means, as Bennett and Hacker stress, is that person feels a certain way as a result of the experiences.  It’s not a matter of the experiences themselves possessing some sort of “feel” or “qualitative character.”

Then there is the fact that in discussions of the hard problem, it is constantly asserted that one’s experiences involve a reddish color, a garlicky smell, and so on.  But here too, that is simply not the way people ordinarily talk.  They would say that the rose is red, not that their experience of the rose is red, and that the garlic has a certain distinctive smell, not that their experience of garlic does.  Common sense treats colors, smells, and the like as qualities of things out there in the physical world, not as the qualia of our experience of that world. 

Now, these odd ways of talking become intelligible (sort of, anyway) if one thinks of the mind on the model of the Cartesian theater.  Suppose that what we are directly aware of are only inner representations of physical things, rather than the things themselves.  Then it might seem that we cannot entirely distinguish different experiences by reference to the objects or modalities of the experiences.  For the experiences could, on this model, be just as they are even if the physical objects didn’t exist and indeed even if the organs associated with the different modalities (eyes, ears, etc.) didn’t exist.  How to differentiate them, then?  Positing a unique “feel” or “qualitative character” for each experience might seem necessary.  Similarly, if it is only our own experiences, rather than physical things themselves, that we are directly aware of, then it is understandable why it would seem that in experiencing a reddish color, a garlicky smell, etc. we are encountering the qualia of experiences rather than the qualities of physical objects.

Aristotelians, Wittgensteinians, Heideggerians, and others would say that this way of carving up the conceptual territory is wrong, and that common sense is right.  Of course, others would say that common sense has it wrong, and that post-Cartesian philosophy was correct to go in the direction it did.  The point, though, is that the “hard problem of consciousness” is not something that arises just from a consideration of the relevant phenomena.  Rather, it is an artifact of a certain set of philosophical assumptions that are read into the phenomena.  And those assumptions are by no means unproblematic or unavoidable.  Indeed, the fact that they generate the “hard problem of consciousness” is itself a good reason to question them.  (I have argued against the mechanical world picture and the Cartesian theater conception of the mind in several places.  For example, I do so at length in Aristotle’s Revenge, and also in Immortal Souls, in chapters 6 and 7 especially.)

All the same, the contemporary debate about the “hard problem” remains worthy of study – not because it teaches us where the truth about human nature lies, but rather because it illuminates the nature and consequences of certain very common and tenacious errors.