Your complimentary articles
You’ve read one of your four complimentary articles for this month.
You can read four articles free per month. To have complete access to the thousands of philosophy articles on this site, please
Mind & Morals
Güven Güzeldere asks where we are now with the mind-body problem.
While the mind-body problem has been around for a long time, it is no less compelling for philosophers today. This is not to say that we are in the same place with regard to understanding it as the philosophers of bygone ages. On the contrary, there has been impressive progress. This progress has been due to great advances in the scientific understanding of the workings of the brain, and to the continual refinement of our philosophical concepts and of the questions we ask about the mind. For these reasons, can we now say that the mind-body problem is nearing a (re)solution, and probably won’t be among the open-ended puzzles of 21st century philosophy?
Judging from the remarkably hot and rather unexpected wave of controversy concerning consciousness in the last decade of the 20th century, the mind-body problem seems to be very much alive and kicking. The term ‘mind-body problem’ actually covers a whole cluster of philosophical issues, such as the unity of self, the intentionality of mental states, and the rationality and agency of human beings. However, it is the problem of explaining our conscious experiences – how it is that we experience sights, colors, thoughts, emotions, as we do – that sits at the heart of this cluster, and that has generated the most vigorous controversy in recent years.
In fact, the renewed interest in the question of consciousness has brought the mind-body problem into the focus of not just philosophical but also scientific debates. Searching for the ‘neural correlates of consciousness’ – the types of brain activity corresponding to particular mental experiences – is now on the scientific agenda of many psychologists and neuroscientists. Philosophers, meanwhile, are busy questioning the nature of the relationship between neural states and mental states, above and beyond a mere correlation.
But how is the problem of consciousness related to the mind-body problem? And if the mind-body problem still seems to some to be far from disappearing from the intellectual landscape of the new century, where do things stand now, as opposed to a few decades, centuries, or millennia ago?
Mind – The Gap!
Our understanding and conceptualization of both body and mind have gone through significant changes, but the gist of the mind-body problem has remained the same for centuries. It is this: just how are body and mind related, in one’s own case or other people? Bodies are seen, by and large, as being physical objects, explained by the respective sciences in terms of their chemical, molecular and neuronal features. Minds, on the other hand, are characterized in terms of lived experiences, joys and pains, imaginations and intentions, thoughts and desires. A host of disciplines, from phenomenology to psychology, cultural anthropology to literature tell us about what goes on in the inner lives that make us subjects as opposed to mere objects.
And that is precisely where the puzzle arises: the concepts and vocabulary and methodologies used to describe bodily happenings overlap very little, if at all, with those employed in the characterization of the mental. Why is that, and what are we to make of the relationship between body and mind (and, for that matter, between bodily and mental explanations)?
We know from our own experience that, at the very least, bodily and conscious mental events are systematically correlated. My intention to move my fingers in a certain way (mental) precedes my typing at the keyboard (physical). The dryness of my throat (physical) gives rise to my desire to get a drink of water (mental). But what is the relation between intentions or desires, described as subjective mental states, and movements or lack of moisture, in particular parts of the body? (One gets a striking realization of how quickly the transparency of this relationship can disappear, in cases of failure of bodily command such as paralysis.)
Sigmund Freud was among many who investigated the nature of the relationship between consciousness and the brain, and his answer wasn’t very encouraging:
We know two things concerning what we call our psyche or mental life: firstly, its bodily organ and scene of action, the brain (or nervous system), and secondly, our acts of consciousness, which are immediate data and cannot be more fully explained by any kind of description. Everything that lies between these two terminal points is unknown to us and, so far as we are aware, there is no direct relation between them.
[An Outline of Psychoanalysis, 1940]
In 1983 Joe Levine coined the term ‘explanatory gap’ for what Freud had called the unknown between the two terminal points of brain function and acts of consciousness. It is seen today as the most difficult aspect of the mind-body problem.
Consciousness and the Mind-Body Problem
In a famous article entitled ‘What is it like to be a bat?’, Thomas Nagel set out the essential problem of consciousness in a stark and rather pessimistic way which still shadows the formulation of related questions. According to Nagel, “Consciousness is what makes the mind-body problem really intractable. Without consciousness the mind-body problem would be much less interesting. With consciousness, it seems hopeless.” [Philosophical Review, 1974]. Until the 1990s, however, the sighting of the term ‘consciousness’ was rare in the philosophy of mind literature, let alone any discussions about it. (There were, of course, a few notable exceptions, such as Paul Churchland’s 1984 book Matter and Consciousness and William Lycan’s 1987 Consciousness).
As consciousness was taking center stage in philosophical as well as certain scientific circles in the early 1990s, some sided with Nagel about the importance and the difficulty of understanding consciousness; other were more upbeat. While John Searle declared the return to the problem of consciousness as The Rediscovery of the Mind (the title of his 1992 book), for example, Daniel Dennett’s answer to Nagel was to publish a book in 1991 optimistically entitled Consciousness Explained. This book was followed by Owen Flanagan’s 1992 book Consciousness Reconsidered, which advocates a milder, but still optimistic, naturalistic position. Fred Dretske presented an information-theory account of consciousness in his Naturalizing the Mind (1995).
The argument that current scientific or philosophical theories can’t explain consciousness in their physicalistic framework was brought back again by David Chalmers in The Conscious Mind (1996). Chalmers introduced a distinction between the ‘easy’ and the ‘hard’ problems of consciousness, putting a twist on Freud’s ‘unknown’ and Levine’s ‘explanatory gap’. He argued that no level of sophistication in understanding the physical aspects of the brain or behavior, or cognitive processes such as learning and reasoning (which he called the ‘easy problems’), can bring us any closer to understanding the qualitative aspects of the conscious mind (the ‘hard problem’).
Taken at face value, this position forces us into a dilemma. One horn of this dilemma is to abandon any hope of coming up with a full explanation of consciousness within the present philosophical and scientific framework, and just accept the mind-body relation as a ‘brute fact’ unlike any other in nature. The other horn, as suggested by another philosopher, Colin McGinn, is that whatever the nature of this relation, we human beings will forever remain unable to fully grasp it (just as monkeys, due to the phylogenetic limitations in their brain function, are permanently blocked from understanding quantum mechanics).
Examined closely, these two conclusions turn out to be not all that different. They can both be proposed as terminal points in the history of the philosophical attempts to tackle the mind-body problem. The mind-body problem has either no further explanation, at least in the present scientific paradigm, or one that shall forever remain a mystery.
As was the case with Nagel and Searle, some philosophers sided with Chalmers, giving the term he coined ‘the hard problem of consciousness’ wide circulation, while others expressed serious scepticism. David Papineau, for example, suggested that perhaps what was needed was not a solution or a resolution to the mind-body problem in its present formulation, but a dissolution of it. Taking Wittgenstein’s advice that philosophy’s job is “to show the fly the way out of the flybottle”, Papineau argued that ‘the hard problem’ was among those philosophical problems that “need therapy, rather than solutions, to unravel the confusions that generate them.” [‘A Universe of Zombies’, Times Literary Supplement June 21, 1996]
The Rise of the Zombies
In this article I want to give you an overview of the recent philosophical debates on consciousness, rather than trying to convince you of a particular view (even if my own view undoubtedly colors my reading of the landscape). But let’s take a look at why the different sides defend what they defend, and what kind of considerations might possibly tip the balance in favor of one of the opposing sides in these debates.
The gist of the disagreement concerns whether or not it is conceivable to think of mind and body as each existing separately, apart from the other. Strong dualists, following the Cartesian line, would claim that both body and mind can exist apart from one another, since they are constituted by mutually exclusive substances, res extensa and res cogitans. Weak dualists claim something less ambitious: that a body can exist and exemplify its behavior all by itself, just as it ordinarily would when connected with a mind. If so, then removing consciousness from an otherwise identical replica of myself would create my zombie twin, who would be indistinguishable from me both physically and in terms of behavior while lacking any conscious inner life. Borrowing from Saul Kripke’s imagery in Naming and Necessity (1972), if God were to create a physical duplicate of our world, right down to the last molecule, but stop before doing the extra work of making sure that the brain events in its inhabitants are in fact felt as sensations, pains or tickles, that would be a zombie world. The inhabitants of the zombie world would behave in ways indistinguishable from us, but they would not be able to enjoy tastes, aromas, sounds, and colors as we do.
The conceivability of such a world is evidence, say those with dualist inclinations, that consciousness is a feature of the world above and beyond all scientifically recognized properties. Those who do not sympathize with dualism, on the other hand, reject the claim that a zombie world is possible (and perhaps even conceivable). That is, Kripke’s scenario cannot be used to undermine a physicalist picture of the world. Rather, they contend, the argument runs the other way around – it is precisely an implicit commitment to a dualist ontology that makes a zombie world seem possible.
The debate on the possibility of zombies contains numerous technical details that cannot be properly covered here. Yet, the following general point needs to be noted. Thought experiments, such as the possibility of zombies, are the bona fide currency in philosophy of mind. In particular, when it comes to debates about consciousness, the measure of acceptability of most arguments is typically based upon their intuitive conceivability. However, it is also generally recognized that conceivability has hardly been a reliable guide through history, in large part due to the continual evolution of scientific knowledge and, consequently, changes in the conceptualization of the relevant subject matters. Thus, it is tricky to defend a position on the basis of a conceptual possibility, which is justified on the basis of what seems ‘conceivable’ to our present thinking. Intellectual history is full of cases where what seemed mysteriously inconceivable to the best minds of the past seems intuitively conceivable today.
In the context of the mind-body problem, for example, what Descartes regarded as the most exemplary and problematic aspect of mind four centuries ago, namely the cognitive faculties, are presently considered as problems being unravelled in well-established research programmes with no hint of mystery attached to them. In contrast, what were then considered rather second-class citizens of the mind, namely the qualitative sensory aspects, have become the prominent placeholders in the mind-body problem.
Nevertheless, philosophical attitudes towards the possibility of zombies seem well-entrenched on both sides of the debate. So rather than rehearsing various pro and con arguments on the zombie question, I wish to bringsome more general considerations onto the stage. These general considerations are relevant to the assessment of two opposing fundamental intuitions in philosophy of mind with respect to consciousness.
Opposing Intuitions and the Dialectics of the Dispute
When it comes to the problem of consciousness, there seem to be two powerful intuitions at work that pull in different directions.
On the one hand, phenomenal aspects of conscious experience, such as a powerful feeling of thirst after a hot day’s hike, the sensation of ice cold water in one’s mouth and running down one’s throat, and the pleasant sense of satisfaction that comes from quenching one’s thirst, do not feature in the vocabulary or the explanatory aims of any science. Neither do the sour taste of lemon candy, or the amber hue and the felt warmth coming from the fireplace, or the fuzzy texture of a ripe peach in one’s hand. These are just a few examples of a whole multitude of phenomenal aspects of one’s ordinary conscious life, and yet they don’t seem to have any place in theories that talk only about particles, waveforms, neuronal structures and the like, all described in terms of physical magnitudes. Perhaps, then, it is unduly optimistic to think that psychology or neuroscience or a naturalistic philosophy that remains within a scientifically legitimate ontology will come up with an explanation of the conscious mind. This first intuition pulls us towards saying that the problem of consciousness lies outside the explanatory range of present-day science.
The second intuition pulls us in the other direction. This intuition tells us that, all things being equal, it is generally reasonable to aim for a scientific understanding of the world, especially when it comes to questions of identifying the fundamental constituents of the universe. This second intuition is ultimately at odds with one of the two direct metaphysical consequences, neither of which is very palatable, of the conclusion based on the first intuition.
If one follows the first intuition, there are two possibilities. The first is to proclaim that consciousness has causal powers, but that uniquely in Nature its causal powers aren’t reducible to the scientifically-identified fundamental elements and forces, so that consciousness eludes scientific explanation altogether. Alternatively we can accept the idea that consciousness itself makes no causal difference, despite our deep-seated belief that the way we behave is affected by our consciousness of the world – how we feel, what we perceive, think or want to do.
The first alternative flies in the face of the impressive success of 20th century science in uncovering the fundamental forces that underlie the causal networks ubiquitously at work in nature. Perhaps it can be argued that aspects of consciousness are to be postulated as irreducible and autonomous fundamental properties of their own. But this view has no evidence in its favor other than the intuition that motivates it. As such, it stands on very shaky ground.
The second alternative, which commits one to some form of epiphenomenalism about consciousness, fares no better. What good is consciousness if it is an ‘idle spectator’ in the flow of our lives? If Samuel Alexander is right, for anything to be is for it to have causal powers. More importantly, can ‘consciousness’, construed as having no causal effect on the world, be the same consciousness with which we are all so very familiar, the problematic character of which constitutes the heart of the venerable mind-body problem?
Where does this discussion leave us? We face two opposing intuitions, each of which is laced with different kinds of difficulties. The arguments in the philosophical literature, given in the framework outlined above, leave one with the sense of a suspended stalemate, without any obvious way of tilting the balance to either direction. Perhaps, however, as it may seem from the brief discussion above, it is not really accurate to say that the two powerful intuitions are on a par. Rather, so long as we find ultimately reasonable the commitment to a scientific understanding of the world, especially in the general context of what counts as a fundamental constituent of the universe, the dialectic between these two intuitions should be regarded in a different light.
That is, in the light of more general considerations, it is the second intuition about commitment to a scientific understanding of the world that is to be honored. And, as such, the first intuition about the gap between the phenomenal and the physical descriptions of the world is to be regarded as a challenge to the project of using explanatory means available and looking for others in innovative research programmes to come up with more satisfactory accounts of the phenomenal aspects of our conscious lives.
Returning to the question posed at the beginning, it seems unlikely at this stage that the mind-body problem will disappear any time soon. Given the open-ended nature of the present debates, it is natural to think that time will tell which way of thinking about consciousness and the mind-body problem was headed in the right direction. Nonetheless, if the above analysis is correct, understanding the nature of the relationship between brain and conscious mind should be viewed as a difficult yet exciting challenge. In any case, the resurrection of the problem of consciousness in philosophical as well as scientific circles is a most welcome event.
© Güven Güzeldere 2002
Güven Güzeldere is an assistant professor of philosophy at Duke University.