Solutions to the Mind-Body Problem?

From Robert Lawrence Kuhn, host and creator of Closer To Truth:

My whole life, I’ve wondered about this: Are human beings purely physical? Evolved at random and destined to die, extinguished forever? Or are we something more? A spirit or a soul with existence beyond?
Which? Most people are sure. Me? I’m perplexed.
Philosophers call this great question “the mind-body problem.” What’s the relationship between our brains and our consciousness, between the stuff in our skulls and the sense in our minds? What are solutions to the mind-body problem?
Philosopher Ned Block provides a road map. “There are three solutions that have been offered,” he says. “One is perhaps the most commonsense solution: dualism, the idea that we have some kind of immaterial soul and the mind is a state of that soul. If dualism is true, then the science of the mind, at least as we now see science, cannot succeed. A second solution is what’s often called ‘functionalism’: the idea that the nature of the mind is a matter of the role that mental states play in causal relations to other mental states, sensations, and behaviors. The idea is to see the mind along the lines of a computer program, or of a computer state, which is defined by and characterized by its relations to other similar states and to sensory inputs and behavioral outputs. A third solution is the one that I favor,” he continues. “It’s ‘physicalism,’ at least for consciousness: the idea that you can construct the mind, at least the conscious part of the mind, in terms of its biological realization in the brain.”
Block rejects dualism quickly “because if dualism is right, then the study of the mind is more in the domain of religion than of science. The functionalists,” he says, “are the computer people. According to the core functionalist idea, the biological substrate is just one of many potential substrates (which could instantiate mental or conscious states). We could make a mind out of silicon just as we could make it out of carbon because the important thing is the functional relations that are embedded in the computer description of it.”
So Block defends the physicalist solution, which asserts that “it’s the biological realization that’s really important”—and which, in the case of consciousness, “looks like it is on the right track,” he says. “All the advances that have been made in the last 20 years in the study of consciousness have been in the study of the brain.”
I ask Block what, fundamentally, is different about a biological substrate from any other substrate, which enables him to favor a biological realization over functionalism.
“This is the most difficult problem about the study of consciousness,” Block says. “It’s the problem of how we can understand why the biological basis of a given phenomenal quality is the biological basis of that quality rather than some other one or none. It’s that problem that makes people dualists because they don’t know how to think about it.”
I continue: What is the difference between mental states based on carbon (organisms) or silicon (computers)?
He responds: “The fear is that you could reproduce the function and so you’d have the same system—which is the functionalist approach—but you wouldn’t reproduce the phenomenal ‘feel’ of it. You’d have made what some people call a ‘zombie,’ which is something that’s functionally like us, but physically and phenomenally different, maybe phenomenally like nothing.”
I persist: But what is left over in the biology, which, after you’ve created all the functions in some other media, accounts for the phenomenal feel or inner awareness? What is this residue? If it’s physical in the biology, why couldn’t you, in principle, reproduce it in the silicon?
“Right,” Block says, “so the two different possibilities are that it’s biological or that it’s functional. If it’s biological, maybe you could reproduce it in silicon, but maybe you couldn’t. The more biological, the more physical, the substrate turns out to be, the more likely it is that a zombie could be made.”
“No, I’m not talking about a zombie,” I protest. “I think a zombie can be made [i.e., fully functional mental states and behavioral output indistinguishable from a sentient organism, but without inner awareness]. I’m talking about a real sentient organism with all the phenomenal internal feeling because that’s what we have to duplicate in order to make it real. If you say we can’t make it, what is the residue you have in your biology that’s preventing you from making it in my silicon?”
“The problem will be if we make a silicon version of human consciousness, how will we know whether we’ve left out something essential,” Block explains. “How do we know what level of description of the human biology of consciousness is essential to consciousness? Furthermore, we do not know now whether we will find a ‘similarity metric’ which will allow us to tell whether another kind of being of this sort really is conscious.”
Here’s where I seem to find myself: If consciousness is purely physical, biological, I can’t imagine why, ultimately, it couldn’t be reproduced in other physical structures, including nonbiological systems.
Block certainly rejects dualism, as do most philosophers, which is why I should speak with a dualist philosopher. I ask Dean Zimmerman how he can defend what most of his colleagues dismiss.
“Anybody who thinks, ‘Well, maybe I can survive the destruction of this body,’ is on the road to some kind of ‘substance dualism’—the belief that the ‘real person’ is not made out of physical kind of stuff so that he or she can somehow exist independently of it,” he says. “Not many philosophers hold this view; there are still a few of us left.”
Zimmerman articulates what it means to be a substance dualist. “A substance dualist is a person who thinks my mental states are possessed by, or they’re exemplified by, a thing that doesn’t have a mass,” he explains. “Such a person has a lot of questions to answer, obviously, one being just how different is this thing that’s thinking from ordinary matter? On the extreme end, people have said: ‘I’m a thinking thing, I know that. I’ve got mental states. They can’t be identical with any mere physical state of physical matter and [so] they belong to a thing that exists outside of time, outside of space; the thing that’s responsible for mental states is totally alien, very unlike any ordinary material objects.’ Others have said, ‘Well, that’s just too different.’ So Descartes is sort of the paradigmatic dualist: He thinks that, ‘I’m certainly in time—I have one thought and then I have another thought and another thought, right, so I’m as temporal as a clock—but I’m not in space [i.e., thoughts do not reside in a place]. Now, I interact with one particular body in space, but I’m not literally there, somehow.’ But other dualists have said, ‘No, I’m more like ordinary material objects than even that. I’m located where my brain is, and I interact with it.’”
In this last formulation, where the stuff would be located where the brain is, I assume that the stuff would still be nonphysical, right?
“Right,” Zimmerman says, “because although the stuff is located in space and pushing things around, as it were, so long as it’s not made out of the same kind of bits as tables and chairs and rocks, it’s nonphysical. This still seems like a respectable kind of dualism to me.”
He adds, “The thing that’s really important is: Do you believe in a soul, and if so, why? Why do you believe in this extra something or other?
I look Zimmerman in the eye and say softly, “What do you believe?”
“So you’re calling me out,” he responds with a smile. “Well, let’s say I feel quite convinced that phenomenal states really are distinct from any material goings on inside this body. So then I wonder: Well, what is their subject? Is it my brain, or part of my brain? I confess that I’m sort of hopeful that it’s not, that it’s something else.”
Fair enough. While most philosophers eviscerate and discard dualism, Zimmerman is hoping for “something else” beyond the physical.
I’m hoping, too, but hope can thwart reason and distort belief. That’s why I speak with Colin McGinn, who has been labeled a “mysterian” in that he doubts human minds can ever comprehend consciousness. So why is he not a dualist?
“Dualism is the view that there are two kinds of substance in the world,” McGinn begins. “There’s matter: Descartes understood matter to be defined by extension—matter is extended substance—which is a spatial notion. And there’s a mental substance, or spiritual substance, which is nonspatial substance. And the essence of the latter, according to Descartes, was thought.”
McGinn continues: “Then Descartes had the question of how these two things are connected to each other. He thought the brain would cause events in the mind. And events in the mind would cause events in the brain. This is how perception worked; this is how action worked. Mind was its own special kind of stuff, existing somewhere. He was rather vague about where it might exist because if it doesn’t have extension, it can’t be in space. So he had the problem of how the two interact. By what conceivable mechanism could a substance whose definition is to be extended in space [brain] interact with something whose definition is to be unextended and not in space [mind]? So that was the classic problem with dualism and the problem of interaction.”
There were other problems, too, McGinn explains. “Where does the mind come from? What’s its origin? If you can join dualism to a theistic view of the universe, then at least you can say that God is the cause of the mind,” he says. “Descartes was a mechanist about how the brain develops: From embryo to childhood to adulthood, the brain develops on its own track by physical processes. But parallel with that, the mind is developing, too. How is it changed? Where does the mind’s change come from? Not from the brain because, according to Descartes, the mind doesn’t have its being derived from the brain, so God is somehow propelling the whole process. What other explanation could we have? So one must bring God in to explain how the mind comes into existence, and even how it develops.”
God brings no satisfaction to McGinn. “As soon as God is invoked,” he states, “all the problems of God come in to haunt you. You have to have a theory in which you explain the existence of God. To most philosophers, and to me, that’s not an acceptable way to go.”
But McGinn also rejects physicalism or materialism. “The problem here really is one of definition,” he says. “If tomorrow physicists discover some completely new force, some completely new dimension, of the natural world, will they say they’ve discovered something nonphysical? Some at first may say, ‘This is nothing like what we know, so it’s immaterial, nonmaterial. Others will say, ‘Well, we discovered it; we’re physicists, so let’s call it ‘material.’”
So physics becomes open-ended, I ask?
“Yes,” McGinn says, “which means that the answer to the question ‘Is physicalism true?’ is ‘vacuously yes’ because the mind is part of the natural world—resulting from biology, evolution, and so on. So in a very broad sense, the mind is part of the material world. I myself think there’s no objection to describing consciousness as a form of matter because, the way I see it, matter has many forms.”
I ask McGinn if he is then using the term “matter” as a synonym for “everything.”
“Yes,” he says. “All there is.”
So McGinn is a physicalist in the broadest sense of the term. And he posits a radically new kind of physical stuff to account for consciousness.
The old brain scientist in me recoils, “Rather extreme, Colin, don’t you think?”
But then I reflect: Maybe current explanations of consciousness are not extreme enough! Perhaps what’s needed is a radically new kind of mental stuff?
For that, I see Charles Tart, a pioneer in parapsychology and altered states of consciousness. He’s an unabashed dualist—but not your daddy’s dualist.
“The place you start is the very commonsense observation that what goes on inside our minds seems to be somehow different from the solid stuff that happens out in the world,” Tart says. “Then things get complicated. For example, after Descartes defined mind as totally different from material stuff, people worry about how they can interact. But mind and brain were defined as noninteracting, so of course it’s a problem.”
He goes on: “I’m a pragmatic dualist. I emphasize the pragmatic because it’s not a philosophical position so much as an attempt to deal with actual events that you can observe. In parapsychological experiments, the mind does things that we don’t know how to make matter do, such as sending mind-to-mind messages (telepathy) or apprehending things at a distance (clairvoyance) or affecting physical matter by mental intention alone (psychokinesis) or healing someone when there’s no physical intervention. And sometimes it works. It works often enough that you know that it happens. Even after you filter out all the noise of unsuccessful experiments and wishful thinking [and fraud], sometimes the mind can do this. Well, the mind is obviously interacting with the material.”
Tart gives his view, which is certainly idiosyncratic. “My take on what’s going on is that clairvoyance and psychokinesis are actually going on in the mind, normally, all the time, but they’re used for what we might call internal communications. The senses feed into the physical brain, and the mind picks up this information by some kind of inner clairvoyance by which the mind reads the state of the brain so that the mind is informed of what the brain is doing. Then the mind influences the brain by means of psychokinesis. I think this is the normal, regular, everyday use of clairvoyance and psychokinesis. And it’s the irregular, abnormal, unusual use of clairvoyance—going outside the body to something totally different in the physical world—which even tells us that clairvoyance exists.”
This is a radically different approach to the mind-body problem. Scientists, philosophers, even theologians, would reject Tart’s hypothesis with world-class swiftness.
“Right, yes,” Tart agrees. “Philosophers usually focus on the mechanism for interaction. Well, these parapsychological effects are the mechanism for interaction. This is what experience and the experimental data force me to conclude. But I’m not offering some absolute philosophical position. I don’t know what the ultimate nature of reality is. But using parapsychological or extrasensory perception (ESP) phenomena to understand the mind-body problem makes the best sense to me. A philosophy of mind that doesn’t take parapsychological data into account is woefully inadequate. It’s leaving out a whole important section of reality.”
Tart calls himself a “pragmatic dualist” because dualism, he claims, is the only way that fits the facts. His wild idea of “internal ESP” to explain brain-mind interaction is double-dose bizarre. That’s why I like it. Though almost certainly wrong, such far-out theories from serious thinkers highlight the inscrutable essence of consciousness.
Even physicalism offers up its own radical explanations of consciousness. To physicist Henry Stapp, the key to consciousness is quantum mechanics.
”For most neuroscientists,” Stapp says, “the mind isn’t doing anything; in fact, it’s difficult to understand why it exists at all.” This materialistic way of thinking, he says, is rooted in “tremendous inertia from the philosophers of the past, philosophers of the classical world, a world that was deterministic and in which the mind played no role. But that physical theory is no longer true; it’s known to be untrue. In the new physics, quantum mechanics, consciousness plays an actual role: The laws of quantum mechanics are not formulatable; one cannot get any predictions out of the theory unless one allows what Niels Bohr calls the ‘choice’ on the part of the experimenter.”
Whereas in classical mechanics “you started with a deterministic understanding of what happens at the lowest level, and this determinism just builds up,” in quantum mechanics, “there is already uncertainty at the lowest level and it builds up as it would in any nonlinear system,” Stapp says, adding, “It explodes.” The point, he stresses, is that the whole brain becomes a single quantum mechanical system. “The core reality upon which quantum mechanics is based is the collapse of wave function, some action in the physical world,” he says. “But it’s associated with a psychological element such that there’s a close connection with the pattern of neurological activity that’s sending out all these nerve impulses. In your mind, there is intent, so that the psychological aspect and the physical aspect are linked together.”
He continues: “In quantum mechanics, but not in classical mechanics, the laws of the physical realm only determine potentialities for something to happen. They do not answer this question of what question is going to be asked. You need something else outside the known laws to determine what the question will be. And once you ask the question, the laws of quantum mechanics determine how the system is then going to evolve. In actual practice, these choices are determined by psychological process. So you have need for psychological processes to make the quantum mechanics work. Bohr had a famous quote: ‘When searching for harmony in life, one must never forget that in the drama of existence we are ourselves both actors and spectators.’ In the classical worldview, we were just spectators; we could only watch what was happening, but couldn’t do anything. In quantum mechanics, we are needed as actors. If neuroscientists would really understand how quantum mechanics works, I think they would recognize that something is missing here.”
Are we all “missing something” here? I hope so. I hope there’s more to me than my brain. But hope, I know, is a great deceiver, and it’s gotten me before. Neuroscience, however, is honest: We know how the brain works, and we’ll know lots more.
But as for the inner, raw sense of personal awareness, I still doubt we’ll ever explain consciousness by neuroscience alone. If physicalism is correct, if I’m just my brain, then, ultimately, consciousness will be reproduced in nonbiological substrates. I do not think it’s possible for the following conjunction to be true: (i) the mind is realized solely in the physical brain, and (ii) the mind cannot be realized in nonbiological substrates. Still, it will be impossible, even in principle, to ever know for sure whether other minds—human, biological, or nonbiological—truly have inner experiences.
Here’s my bottom line: Explaining consciousness will require something radically new—either finding physical stuff beyond current boundaries or revealing the reality of nonphysical stuff.
Which is why trying to solve the mind-body problem edges us closer to truth.

Robert Lawrence Kuhn speaks with Ned Block, Dean Zimmerman, Colin McGinn, Charles Tart, and Henry Stapp in “Solutions to the Mind-Body Problem?”—the 18th episode in the new season of the Closer To Truth: Cosmos, Consciousness, God TV series (57th in total).
The series airs on PBS World (often Thursdays, twice) and many other PBS and noncommercial stations. Every Thursday, participants will discuss the current episode.

P.S. Click here to visit our Closer to Truth archive.

Category: Closer to Truth


6 Responses

  1. Congratulations! You have discovered that neither monism (physicalism) nor dualism answer the mind-body problem. For some reason modern people are unable to go beyond these two options, but it should be noted that Socrates/Plato originally had humans composed of mind, body, and spirit. Modern psychologies like Freud’s id, ego, and superego are also triune.

    I know that you do not expect me to solve the mind-body dilemma in one posting, but if you log on to my website,, I will give you more information and tell you how to order my new book, DARWIN’S MYTH which will give you all the details.

  2. Tom Clark says:

    “Explaining consciousness will require something radically new—either finding physical stuff beyond current boundaries or revealing the reality of nonphysical stuff.”

    A third option not covered in your very nice review of the “hard problem” of consciousness is representationalism: that phenomenal experience is non-causally entailed by being the right sort of world-representing system. See Thomas Metzinger’s great new book The Ego Tunnel for one version of this theory, reviewed at You might also enjoy which considers the puzzle of how conscious experience could possibly influence behavior.

  3. Bro. Clark I am glad the we can agree that there is no such thing as a “substantial” self. How can a relational spirit be considered a substance?

  4. “Neurosciences have irrevocably dissolved the Judeo-Christian image of a human being as containing an immortal spark of the divine”
    Quote from The Ego Tunnel found on Tom Clark’s website.

    Bro. Clark, I think that you and your friends need to wake up and understand intellectual reality of today’s world. Today’s science has not irrevocably dissolved the Judeo-Christian worldview, it has dissolved the Western philosophical world view based on Socrates, Plato, and Aristotle. This is very the world view that is the basis of modern science.

    The phrase “immortal soul” certainly does not appear in the Hebrew Bible. Nor does it appear in the Greek Bible. It appears in Greek philosophy, which was used by theologians to explain Christianity and by scientists to develop modern science.

    The Bible was written independently of Greek philosophy and its world view independent on it. Science on the other hand is based on the Greek belief that reality is based on absolutes, and the dissolution of this understanding by Einstein’s Theory undermines its very existence as The Ego Tunnel clearly demonstrates.

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  5. George Faulkner says:

    I disagree with the author Kuhn’s conclusion that “Explaining consciousness will require something radically new—either finding physical stuff beyond current boundaries or revealing the reality of nonphysical stuff.” All of science so far shows us that monism is the most consistent and economical explanation for the “world” we experience, whether we call it naturalism or materialism. As noted, dualism leaves us with too many extra problems.

    I think the “hard” (or “qualia”) problem can be solved by understanding that it is a category error or mistake of “misplaced concreteness, to use Alfred North Whitehead’s term. We often seem to forget that the “physical” or “material” world itself is a mental construct, based on analogizing from subjective sensations like hardness, distinct boundaries, solidity, separateness, sameness, etc. From this process of course we initially came up with the 18th Century bouncing billiard balls image of the material world, which we all agree is no longer accurate physics, but we still seem to unconsciously rely on.

    So, while a lot of Whitehead’s process philosophy may be outmoded, his idea of panpsychism seems to me to solve the mind/body problem by simply implying that all interactions have an internal or “subjective” (loosely defined) and an external or objective perspective. This allows our very human sense of “mind” to be simply a matter of greater complexity (as most cognitive scientists would claim anyway), rather than something altogether new. The “mental” exists in all physical interactions, but of course some types are organized in animals’ nervous systems with self-correction feedback loops, internal models to compare with sensations of the “outside” of one’s boundaries, etc. Metzinger and others are trying to solve somewhat more specific problems, such as how human internal models construct and maintain a unified “self” image. But it still seems that the only solution to the more basic “hard problem” is to understand that our internal experience is the sum total of the internal “experiences” (or call them “sensations,” “signals,” “energy” or “information” flows, or whatever) of trillions of synaptic electro-chemical interactions, organized by evolution in very specific ways — excluding of course the “survival need” to solve mind-body and other philosophical problems.

    The panpsychic solution, as I hope I’ve described it, is not some New Age, amorphous “cosmic consciousness” or another form of dualism. It is simply recognition that we need to start from the interior, “mental,” or subjective first and then recognize that the exterior, bodily, material aspect is itself a construction of the former. It still allows for the “reductionism” of science showing how parts at a lower level, organized is specific ways, can make higher level “wholes.”

  6. How i wish some of these history/philosophy could live in Houston,TX i need help right now in the subject.!

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