What Is Consciousness? (什麼是知覺?)

What Is Consciousness? (什麼是知覺?)
[創意組織 ]
(2003/08/19)

What Is Consciousness?

ARE you conscious? How do you know? What is consciousness-our thoughts, feelings, hopes and dreams; the hidden voice of our private selves; our inner identity? What might consciousness consist of? All of us think we can understand consciousness, but none of us can explain it--therein lies its mystery. Think about yourself reading this chapter, and at the same time, observe yourself thinking. This is self-awareness, the interior mental experience we call consciousness. But why should you be self-aware at all? Is there something special about consciousness--something unique to humans beings, something not found in computers, something of the mind not in the brain? Many scientists, taking the so-called reductionist approach, believe that the inner voice we all experience is simply the illusion of selfhood, manufactured by our brain functions. These people subscribe to materialism, the philosophy that only the physical is real and that nothing nonphysical can exist. But there are a few scientists who wonder whether consciousness may be a fundamental part or property of existence, like matter, energy, space-time--and whether some obscure form of stuff may constitute our private selves. Then there are many people who believe in the existence of an independent, metaphysical spirit or soul, which is somehow an attribute of all human beings and in concert with the human brain forms the human mind. These people--traditional theologians are an example--espouse dualism, the philosophy that two radically different forms of stuff exists in the world: mind, the essence of which is thought; and matter, the essence of which is extension in space and time. Dualism traces its roots to the ancients but was famously expounded by the seventeenth-century mathematician and philosopher Rene Descartes, who also said, "I think, therefore I am," thus asserting the primacy of consciousness. Materialism and dualism have been the two principal combatants in the philosophical tug of war commonly known as the mind-body problem. But there are related (and somewhat less respectable) belief systems--such as idealism, which asserts that mind is the reality and matter the illusion, and solipsism, which holds that the self is the one and only true reality. (Modern variances of materialism, such as Eliminative Reductionism and Functionalism, are discussed in the books of our guests.) Why is consciousness so fascinating? And why is it such a hot topic these days, with an academic journal devoted solely to consciousness studies, a proliferation of popular books on the subject, and a series of interdisciplinary conferences at the University of Arizona? To provide you with some insights, we enlisted the help of two philosophers, two physicists, and an anthropologist who is an expert on extrasensory perception. Remember, we give no assurances about truth--just a promise to get you closer.

PARTICIPANTS

David Chalmers, a philosopher at the University of Arizona, is the author of The Conscious Mind: In Search of a Fundamental Theory. Dave wonders whether consciousness may be just as fundamental as matter and energy.

Dr. Marilyn Schlitz is research director of the Institute of Noetic Sciences, a center devoted to an integrated understanding of consciousness. Marilyn believes that consciousness extends beyond the individual body and brain.

Dr. John Searle, a leading philosopher of mind at the University of California, Berkeley, is the author of many books, including The Mystery of Consciousness and The Rediscovery of the Mind. John believes that while consciousness is a real phenomenon, it arises solely from the brain.

Dr. James Trefil, a professor of physics at George Mason University, is the author of Are We Unique: A Scientist Explores the Unparalleled Intelligence of the Human Mind. Jim offers the mainstream scientific view that consciousness consists entirely of electrochemical activity within the brain.

Dr. Fred Alan Wolf, a non-mainstream theoretical physicist, is the author of The Spiritual Universe: One Physicist's Vision of Spirit, Soul, Matter, and Self. Fred suspects that consciousness may be the "real reality" and matter a dreamlike illusion.

ROBERT: John, you're one of the leading philosophers of mind. Why is consciousness such a mystery?

JOHN: We don't know how to explain it. Compare consciousness to physics. We're doing pretty well in physics, even though we have some puzzling areas, like quantum mechanics. But we don't have an adequate theory of how the brain causes conscious states, and we don't have an adequate theory of how consciousness fits into the universe.

ROBERT: Why is consciousness suddenly so hot?

JOHN: Well, in a way, the puzzling thing is why hasn't consciousness always been hot? It's the single most important fact about our existence, except for life itself. Consciousness is the most descriptive thing about human beings. So what happened to consciousness? There was a period of nearly a hundred years--most of the twentieth century--when the scientific consensus believed that there was no way to construct a scientific theory of consciousness. William James and many of the leading thinkers in the late nineteenth century assumed that there was just nothing useful one could say about it. So what has happened recently, I think, is not that we've suddenly discovered consciousness, but that we've rediscovered something we should have been studying all along. We have gone back to what is a normal preoccupation of curious, self-perceptive human beings: How does our own consciousness work? What makes consciousness hot now is that we've overcome the silliness of a certain era, when people thought you couldn't really say anything about it.

ROBERT: We haven't fully overcome prejudice against the subjective. Many scientists still feel that studying consciousness just spends our money and wastes our time.

JOHN: But they don't dominate the scene the way they once did.

MARILYN: Certainly consciousness has been hot, and within our own culture we're just beginning to wake up to this idea. What is unique about this moment in human history is that, for the first time, we have a convergence of worldviews. We have available all of the wisdom traditions--sacred texts from different cultures--that previously only a handful of people could access. Now you can download it all on the Internet. If you add the advances we're making in the neurosciences and cognitive sciences to the teachings of the wisdom traditions, the result is an unprecedented interface between two diverse ways of knowing and being in the world. We're suddenly being compelled to re-evaluate the significance of consciousness, and to confront the notion that our subjective and our objective dimensions are probably one and the same.

ROBERT: Dave, over the last ten years, what have you seen change in our perception of consciousness?

DAVE: The central change is a shift in science. Many scientists are now willing to take subjective data seriously, as legitimate data. Inner feelings and awareness are appreciated as real and manifest in the world. You have to take your own states of consciousness at least as seriously as, say, pointer readings on physical meters. Electronic recordings of the brain are data, but so also are accounts of inner experiences--all these are data, too. Many scientists are now prepared to consider consciousness as a real phenomenon, as something that can be connected to everything else. But that's what science is about; it's about building connections between different phenomena.

ROBERT: John, what are some of the traditional explanations for consciousness? Don't critique them now; you'll get your chance later.

JOHN: That's hard to resist--critiquing them. The standard view, the one that the man and woman in the street believe, is usually dualism. Dualism is the idea that in addition to the physical world there's a separate mental world--an independent mental reality of consciousness that's not part of the ordinary physical world. In opposition to dualism is materialism, which is the prevailing view among professional experts--psychologists, philosophers, neurobiologists. And materialism is the idea that the material world is all there is, and either consciousness has to be reduced to brain states or computational states or something absolutely physical like that, or else it doesn't really exist at all. So the big choice today is between dualism, which says that we live in two separate worlds, a mental world and a physical world, and materialism, which says no, it's all physical.

ROBERT: Zombies, Dave. What are zombies, and what do zombies have to do with consciousness?

DAVE: Zombies don't exist. That's what's interesting about them. Zombies are hypothetical creatures. They're physically identical to you and me; they look the same. They walk, they talk, they behave; they're incredibly sophisticated, just like we are--but they aren't conscious. They have no inner lives, no awareness, no subjective experiences. This is what makes these strange, spooky beings zombies. Again, the interesting thing about zombies is that they don't exist. We're not zombies. And that's precisely what we want a science of consciousness to explain. Why aren't we zombies? Why are we conscious beings? Why did nature produce self-aware beings like us? We human are much more than this interesting physical structure of body and brain; we have subjective inner lives.

ROBERT: Your recent book, The Conscious Mind, makes a claim that consciousness is as much a fundamental building block of reality as is matter, energy, space, and time. Do you really believe that? Or are you just tweaking us a bit?

DAVE: Coming at the question of consciousness as a scientist, taking the scientific worldview, I ask simply, "What do we want to explain?" Let's start with the data. There are two kinds of data about consciousness. There's third-person data--what we observe about others: physical presences, biological structures, behavior, complex language, reactions, and the like. But then there's also first-person data--what we observe about ourselves--and this data we have to take incredibly seriously. Included here are the internal subjective sensations that are highly personal--such as, what the mind "feels like" to us, the complex experience of vision, mental immersion, and thought. So data about consciousness can be bifurcated into third-person data and first-person data, and I think there's reason to believe that these are irreducible to each other. What we want a science of consciousness to do is to take both persons seriously: the third-person data about brain and behavior and the first- person data about the mind and consciousness. We need to take inner experience as seriously as outer behavior, and connect them up in a systematic theoretical paradigm. And that's what we need for a true science of consciousness.

ROBERT: Marilyn, as an anthropologist, you're a leading researcher in parapsychology, which is the scientific study of anomalous, sometimes startling mental phenomena. How does parapsychology reflect on the nature of consciousness?

MARILYN: I think that we can assume that there's a physical, material basis to consciousness; all we have to do is take a sledgehammer and bang somebody over the head to see a reduction in consciousness. The key question takes the next step and asks whether consciousness is anything more than what is physically or materially determined? Most cultures believe that we're also capable of transcending this physical, material aspect of our being, that our consciousness is capable of stretching or expanding--stretching out into the world, expanding beyond our bodies. There's a great deal of evidence in parapsychological research that suggests that there's some non-local exchange of information--such as between two people (i.e., telepathy)--that at the very least extends our definition of materialism. Though it may provoke skepticism, statistically significant data from parapsychology begins to support some kind of dualistic model, which John [Searle] mentioned before.

ROBERT: Lest he be miscast, John didn't mention dualism with much joy, but we'll let him have at you later.

ROBERT: Jim, you're a physicist who has written a book on consciousness, Are We Unique? What do you think--are we unique, and is consciousness a part of our uniqueness?

JIM: I think it's possible to be a good twenty-first century materialist who thinks that the brain is a physical, chemical system that operates according to known, or at least knowable, laws and still think that there's something different about human consciousness--something remarkable, which can't be reproduced by machines and hasn't been seen in animals. This was the "uniqueness" question I approached in my book. And I must tell you, it was a question about which, as a scientist, I had a deep emotional concern. How do you reconcile the scientific view of a human being as basically a machine with the first-person experience that Dave [Chalmers] talked about: the sure sense of my inner self that I am not a machine? That's one of the things I try to get at.

ROBERT: And that's a fundamental issue of human existence. Fred, you're also a physicist, trained in theoretical quantum physics. Yet you've written extensively on the spiritual essence of the universe and on the spiritual nature of human beings. Give us your take on consciousness. Dualism? Materialism? Where do you stand?

FRED: I choose "C," none of the above. We may be missing the boat here by adopting a view that one of these categories must be correct, whether empirical objectivity and physical materialism on the one hand or the rather archaic and simplistic dualistic models on the other. Possibly, there's a third choice--a choice that says that there's something beyond all materialism, beyond the physical world, out of which all reality, the whole of existence, projects. This would overwhelm traditional dualism--and I take this view not as a mystic but as a quantum physicist. I think that our most modern understanding of the physical world suggests that there may be an ineffable realm, a mystical realm, an "imaginal" realm, out of which the physical world pops into existence. Kind of like what [the German physicist and pioneer of quantum mechanics] Werner Heisenberg suggested when he brought the notion of consciousness into physics--when he said that it's the observer that creates the observed simply by the act of observation. So I answer the question of consciousness not by speculating about what it is, but by specifying what it does.

ROBERT: Let's get back to basics. Let's get some traditional characteristics of consciousness.

JOHN: The obvious characteristic is the one we all experience when we wake up in the morning. There are these qualitative, subjective states of sensation or personal feelings or inner awareness. For every consciousness state, there's something that it "feels like" to be in that consciousness state. So we know what it is to taste beer, and we know that tasting beer is different from feeling an itch, and that both are different from smelling roses, which is nothing like the sensation of eating steak, and all of these are feel different from thinking about mathematics. Now, all of these things we "feel like" are conscious states; they all have this qualitative, subjective, inner character. So consciousness is what happens when you wake up in the morning from a dreamless sleep, and it continues throughout the day until you go to sleep again, or get hit on the head, or die, or otherwise become unconscious.

ROBERT: But don't all those "feel like" states of the mind relate directly to physiological states of the brain?

JOHN: Of course they do. In my worldview, there isn't any question that consciousness is caused by brain processes. Anytime I have any doubts about that, all I have to do is take an aspirin, or drink too much whiskey, and I detect immediately the effect on my consciousness of changes in my brain.

ROBERT: Marilyn, what about this clear correspondences between mental states of the mind and physical states of the brain? When you drink too much alcohol, you do feel a little dizzy; when you get hit on the back of the head, you do see stars. Don't these facts undermine arguments for the dualistic nature of consciousness?

MARILYN: We make certain assumptions, and right now--at this point in human history, in this culture--we have a materialist worldview and a physicalist, reductionist approach to existence, whereby all explanations are reduced to fundamental physical properties. Therefore the questions that scientists commonly ask today about the nature of consciousness derive from this materialist worldview. They ask physical kinds of questions. The physical nature of consciousness is very real, but perhaps we need a broader definition of what is physical. If you look at the wisdom traditions--Buddhism, for example-you see a materialist model, too, but this kind of materialism defines matter to be much more encompassing that what we currently maintain within the physicalist model that defines Western science.

ROBERT: Dave, why do you talk about "easy problems" and "hard problems" in the study of consciousness?

DAVE: There are many different problems of consciousness. Even the word "consciousness" doesn't mean the same thing to all of us. When I'm talking about consciousness, I mean this. When you're talking about consciousness, you mean that. So there are many problems. Problem one has to do with behavior. How is it that we're able to get around in the world, to respond appropriately?" For example, I look at you and say, "That's Robert." I can behave towards you; I can point at you; I can talk about you.

ROBERT: Nicely, I hope.

DAVE: Only if you're having a good day. But that's what we might call the relatively easy problem of consciousness: how is it that I can behave toward you in this conscious way? Now, the hard problems of consciousness are the problems of first-person subjective experience. While I'm doing all this sensing, acting and behaving--looking at you, talking to you, talking about you--I'm also having inner, subjective experiences of you. It "feels like" something.

ROBERT: Simple as it sounds, this "feel like" question is fundamental for understanding the true nature of consciousness.

DAVE: Right. I have internal visual images of you; I have thoughts about you running through my mind, maybe even with a little emotional affect attached. But why is all this internal stuff going on? Why is there a first-person inner life at all? Granted, it's probably connected, in some way, in my brain. But why is it that my brain processes produce these subjective experiences of inner awareness? That's the hard problem.

ROBERT: Dave, do you see Jim [Trefil] over there? Usually he's a nice guy. But in his book about consciousness, here's what he wrote about you, and I paraphrase: If consciousness were a football game, you, Dave Chalmers, would forfeit right after the opening kickoff. In other words, he's saying that you seem to have thrown up your hands and given up too quickly in simply rejecting the mainstream materialist view. Now, maybe the metaphor should have been rugby [Dave is Australian], but you get the point.

DAVE: Jim said that?

JIM: The point is that there's a standard saying in the sciences that extraordinary claims require extraordinary proof. And so when you want to say, as Dave does, that we have to create this new category of reality which is somehow related to consciousness--or if you want to say that there's this other kind of dimension or this undetected part of our world--the first thing I want to know is, Well, OK, why am I forced to consider this extreme possibility? Unless I see data saying that there's no way that I can avoid this unlikely scenario--that there's no way to explain all the things we're talking about just on the basis of the physical brain alone--then I'm not going to take that next step. Until I see proof of that, I'm not going to look beyond the physical.

FRED: You can't even explain physics without going beyond the physical! That's the answer, and it's very clear. If we talk about quantum mechanics, we have to talk about a quantum wave function, something that is clearly not material, not substantive, yet necessarily it has to exist in order to explain the simplest physical phenomena.

JOHN: But isn't there a rather simple verbal shift that will at least get us to the point where we can address the same question? The traditional categories of the mental and the physical, as they're commonly used in popular speech and even in much of the sciences, are essentially seventeenth century categories. And they're really out of date. What we're interested in is "How does the world work?" Now, one of the things I think we do know about the world is that consciousness exists. It's a real phenomenon in a real world, and it's a biological phenomenon caused by processes in the brain. Maybe consciousness is caused by some new kind of brain systems; we don't know that yet. But certainly consciousness is caused in the brain. By the way, Jim, I was amazed that you were seeming to deny consciousness to animals. Let's get serious here; there isn't any doubt that my dog Ludwig is conscious.

JIM: So's my dog.

ROBERT: We're now going to compare dogs?

JIM: No, but the point I was making was this. Everyone has his or her own idea of how the brain will ultimately be determined to produce consciousness. My own particular idea comes from complexity theory--from what are called emergent properties. I think consciousness is an emergent property. Consciousness requires lots of neurons [the hundred billion cells in the brain that carry information as electrical impulses] to be stuck together, and like it or not, dogs have fewer neurons than humans do. This is very much like what John [Searle] said--that these categories of consciousness are a seventeenth century concept. We have this one word, "consciousness," and it has to describe everything.

ROBERT: I agree that this same word has to subsume every possible collection of neurons, whether found in humans, dogs, or worms. We don't yet know enough about the issue of mental awareness--let alone self-awareness--across species, and this is a problem, though I'm not sure it's the problem. Jim, do you think there's a significant difference between human consciousness and whatever exists of a similar nature in nonhuman animals?

JIM: Yes, I think so. At least you can make that argument. Someplace along the evolutionary track, you get to a certain complexity, and suddenly the properties of a system become fundamentally different. And such emergence has happened many times on the curious path to human beings--or to mammals or sea cucumbers.

JOHN: There are all kinds of differences between human and animal consciousness, but the essential thing is what Dave [Chalmers] was pointing to--namely, that they both have subjectivity, they both have these qualitative, inner experiences--and that's what we are all trying to explain. How do these qualitative, inner experiences fit into the rest of the universe? And what I'm suggesting is that the traditional categories are not the way to pose the question.

DAVE: There's no question that a really deep connection exists between the brain and consciousness. If you duplicate my brain in reality, you're going to duplicate my consciousness in reality. You affect my brain, you affect my consciousness. The real question is, What is it about the brain that can explain consciousness? You can tell stories about how the neurons interact within the brain, such as how the prefrontal cerebral cortex produces motor responses [i.e., what happens in the brain to cause movements like fingers playing a piano]. This will explain only how I behave. It will explain how I can talk to you, and how I react to your constant questioning, and so on. Physical processes are really good for explaining physical structure and physical behavior. But once we get to consciousness, it seems that we're dealing with a whole new class of problems. It's no longer a problem about the structure and behavior of physical objects--it's now about the internal qualitative feel of inner mental awareness. And here is where the standard method of physical explanations may well need to be amended.

JOHN: [To Dave Chalmers] Do you believe in levels of consciousness? Is a mouse conscious? A fly? A virus? A piece of wood?

DAVE: I think there are degrees of consciousness, and there are very different kinds of consciousness. We humans have a particularly complex consciousness, as expressed by our language and as represented by our concepts. And we are conscious of ourselves. Now take a dog. A dog may well be conscious of the world around it--the internal hunger, the external food, fire hydrants, other dogs. But it may not be conscious of itself in the same complex, self-aware way that humans are. Go on to a fly. A fly is still sort of looking out at the world, and it may have some really simple kind of visual perceptual field. I don't see a reason to deny a simple kind of consciousness to a fly. The farther down you go on the chain of animal complexity, the more diminished the degree of consciousness, but it's very much an open question.

ROBERT: Fred, how do you envision degrees of consciousness?

FRED: I'm not sure if the degree of consciousness ever diminishes. I'm not even sure that we humans are so super-conscious ourselves. I look at an anthill and I'm amazed at how human-like these simple creatures behave. The real question is trying to define what we mean by consciousness. This is the really crucial point that scientists need to think about. How do we define consciousness? What are the models we can use to approach the question? Materialism is not going to work. Pure subjectivity [i.e., idealism, the philosophical theory that only the mental is real and the physical is an illusion] is also not going to work. But something that somehow encompasses the two might work. This synthesis is what has to be brought about. Quantum mechanics might be the place to start to look. But even quantum mechanics is not going to be the final answer.

JOHN: I don't see the problem. Definitions sometimes come in two kinds: There's the detailed, comprehensive, technical definition that you give at the end of an investigation; we are nowhere near being able to do that for consciousness. But there's also the commonsense definition, where you simply identify the target of an investigation; that's rather easy. Let's try the commonsense definition here: Consciousness consists of these qualitative, subjective, inner states. You pinch yourself and you produce an altered state of consciousness-that is, you feel a pain that you didn't feel before. Now, that's what we're trying to explain. Eventually, of course, if we had a perfect science of the brain, we'd be able to give a comprehensive, scientific definition of consciousness. It would be like moving from the definition of water as a colorless, tasteless liquid to water as the molecule H2O with a precise bonding structure. Regarding consciousness, we're still in the "colorless, tasteless liquid" phase. But there's no fundamental problem.

ROBERT: Would that comprehensive, scientific definition of consciousness include the possible need for a separate entity or independent category?

JOHN: No separate entity, not for me. I don't know about an independent category--but the point is that we want to be able to recognize that consciousness is a real feature in a real world. It's a biological phenomenon. It's real in the same sense that digestion or photosynthesis is real biological phenomena. We're not going to get rid of consciousness, or show that it doesn't really exist or that it's all an illusion.

MARILYN: Let's build on that idea. If consciousness is a construct as much as it is a process--and as we begin to try and do science on consciousness--we need to recognize the dichotomy between the first- person and the third-person data that Dave [Chalmers] offered us and expand it. We have our first-person subjectivity--that inner experience. We have the third-person objectivity, which we can study using electrodes and PET scans and different kinds of physiological monitoring techniques. But there is another "person." I believe we must include in any appreciation of consciousness the second-person perspective, which is the relational aspect of consciousness. All of our concepts, our symbols, the meaning systems by which we can even have this conversation, are based on a shared set of cultural assumptions. I'd like to use this second-person perspective to comment on what Jim [Trefil] said--that until there are data to support the notion that there's something more than a physical brain state of consciousness, he won't be willing to buy it. I would say that a key to understanding consciousness is the problem of the second person. I seek the liberation of the second person in the study of consciousness. I believe that a second-person perspective provides a fresh set of assumptions, a new cognitive framework, in which we can formulate our opinions, ask our questions. And so I would submit that there are data out there suggesting that consciousness is more than just the brain--or at least suggesting that the brain's capacities are far more than what we've currently reduced them to. But because our worldview--our Western scientific way of thinking--limits our assumptions, we interpret those data with a particular set of filters, which may limit our ability to actually get closer to truth about what is the nature of reality.

JIM: But now you're introducing the interaction between two brains, which of course is much more complex than the processes within a single brain itself.

MARILYN: But you can't have consciousness without a multiplicity of beings from all levels of psychological strata.

JOHN: It seems to me that you can have subjective states of awareness even if you're Robinson Crusoe on a desert island. You don't need a second-person perspective for consciousness. The point that Dave [Chalmers] was making--I was trying to make the same point--is that consciousness is a first-person mode of existence. Of course, you can't have a fully developed consciousness, of the kind we have, without second-person activities as well. You need language, which you can't have unless you can interact with other consciousnesses. Nor can you explain consciousness without appealing to the third-person fact that we have objectively existing brains in our skulls. But the actual existence of conscious states--the actual feeling of a pain, or the taste of the beer--these are first-person experiences.

ROBERT: Are you using a third-person analysis of biological processes to equate, say, gastric secretions in the stomach to consciousness "secretions" in the brain?

JOHN: Yes, absolutely. That's the point I'm making. Maybe we can create consciousness artificially in some machine, but as far as we know to date, it exists only in human brains and in certain animal brains. And it's probably not worthwhile worrying about how far down the biological strata consciousness goes. Since we don't know how it works in our brain, we're not yet ready to worry about flies.

ROBERT: Dave, do you agree with the gastric secretions analogy?

DAVE: The difference as far stomachs are concerned is that you can tell a physical story to make it transparently clear just why you find those gastric secretions there. You tell a physical story about the brain--how the neurons hook up to each other, how brain areas are wired together--and you can say that this is what produces consciousness, and probably it does, but does that explain why it produces consciousness? No. Consciousness seems to be an irreducible, further fact that seems to be tacked on to the story somewhere. What we need in the science of consciousness is an explanatory theory that connects brain processes and mental self-awareness.

JIM: Doesn't that depend on what kind of explanation it turns out to be? Look at where we're starting. It's like sitting around in 1600 and arguing about electronics four hundred years in the future. We have no idea what the science of complexity is going to tell us about how the brain is organized.

ROBERT: I think it's fashionable to underestimate how much we do know about the brain and overestimate how much there is yet to know. I'm not sure whether what there's yet to know will qualitatively increase our understanding of the neural basis of first- or second-person consciousness.

JOHN: We do have one fact we can start with. We know that it happens--we know that the brain produces consciousness. Now, from the fact that we know that the brain does it, we can at least formulate a well-defined question: How does the brain do it? That's the basis on which we have to proceed. Of course, it may turn out that our existing neurobiological paradigms are inadequate to explain the special essence of consciousness and maybe we need some complete scientific revolution. But we have to recognize that, one, consciousness exists, and two, consciousness is caused by the brain.

ROBERT: John, tell me about those who would take issue with you and deny altogether the very existence of consciousness. The brain is real, they contend, but consciousness is not. What are their best arguments? I want you to honestly be your own opponent here.

JOHN: I've dealt with these guys for years; I don't have any problem telling you their arguments.

ROBERT: I'm listening carefully.

JOHN: OK, here we go. Their argument goes as follows: Science demonstrates that the way the world works is entirely physical or material. Nothing exists that is not physical. Therefore if some people still believe that consciousness requires something else to exist--something in addition to the physical, some touchy-feely, airy-fairy kind of stuff like Searle kind of talks about--then it must be unscientific and hence imaginary. Consciousness can't be anything like that. So consciousness is in fact an illusion--an artificial, artifactual, deceptive illusion generated by!K, and here follows whatever your favorite theory is. Nowadays the favorite theory is "by computer programs in our brains," and these programs, we're told, is all that consciousness ever was. How about that? Was that honest enough?

DAVE: For much of this century, science has been afraid of subjectivity. Science is meant to be objective, right? No subjective elements allowed. But consciousness is subjective by its very nature, so some people conclude, by a priori definition, either that science can't touch consciousness or that consciousness doesn't exist.

ROBERT: It's interesting how the latest brain theory always employs the latest technology--modern mechanisms as modern metaphors. At the beginning of the century, the brain was likened to a telephone exchange, with wires plugging and unplugging. Then electronic circuits, then simple computers, then holograms. Remember the hologram period of brain theory, where all parts of the brain stored all the same memories? Recently, the metaphors have grown more intricate, with parallel computing, and now even quantum physics and complexity theory.

JOHN: Look back all the way to the Greeks. Greek thinkers thought that the brain was a kind of catapult.

FRED: There's something very important that we're leaving out. Even the notion of a subject is questionable. Take Buddhism's concept of consciousness: there is no subject. It's something that arises momentarily, spontaneously, and then disappears.

ROBERT: Fred, is consciousness a useful concept?

FRED: Well, sociologically, we need to understand consciousness, because we build pictures of the world based upon how we envision the world. If we can understand how brains are conditioned by certain ways of seeing, if we can understand how differences in perceiving can yield differences in actions, then I think we've come a long way. Take some mundane examples: In advertising, how do images and ideas affect the minds of the audience? In politics, why did we choose this candidate and not that one? In Hollywood, why do we like that movie star and not this one? All of these attitudes have to do with the nature of our human consciousness.

ROBERT: Jim, wouldn't many of your fellow physicists believe that research funds spent on consciousness would be more productively employed in building larger accelerators?

JIM: No, I think there's a pretty good recognition that the study of the brain, in which I embed the study of consciousness, is the real frontier for the next century. What happened, as John [Searle] alluded to, is that we now think we understand how to ask the questions. We start with neurons. We understand a little bit about how the brain works and we see how we can understand a whole lot more. And that's why, in the scientific community, brains are hot.

MARILYN: At this point, I don't think we do know the right questions to ask about consciousness. I think we're just beginning to formulate some questions, let alone come up with any answers about the nature of this great mystery.

ROBERT: John, do you think that the wisdom traditions and religion can make significant contributions to the study of consciousness?

JOHN: I'm open minded. My theory is, use any weapon you can lay your hands on, use any data you can find. If you can get interesting data from mystics or swamis or people in altered states, that's fine by me; just use all the weaponry you can. But I think that when ultimately we solve the problem of consciousness, we'll have done it by examining actual biological mechanisms. You're going to have to get deep into the thalamo-cortical system and find out how these critical brain processes work.

ROBERT: But once we do, when we have finally worked out a comprehensive biological mechanism of consciousness, will you then be satisfied that consciousness is completely explained?

JOHN: Absolutely!

ROBERT: Marilyn, will you satisfied by biology alone?

MARILYN: I would say that a complete explanation of consciousness will require an integrated research agenda. Surely we acknowledge the physical dimensions that John [Searle] and Jim [Trefil] refer to, but we also need to recognize that consciousness can't be completely explained in isolation from other people--there's a social, cultural dimension. Going further, I also think there's compelling data to suggest that consciousness also includes a transpersonal component, something beyond individual awareness. The mystics and sages of all the ages haven't all been deluded; their insights and visions can't all be categorically rejected. Ultimately, a complete explanation of consciousness is going to have to accommodate these various perceptions.

ROBERT: It seems we've found a fundamental disagreement here.

JOHN: I don't think there's any out-of-brain consciousness.

ROBERT: And you do, Fred?

FRED: I'm convinced there is. I rely not only on my readings of the traditions of many cultures and religions, but also on some extraordinary experiences that I personally have had with shamans in various parts of the world.

ROBERT: Jim, no out-of-body consciousness for you, right?

JIM: I'll keep an open mind, but right now I don't see why we need it.

DAVE: John says that consciousness is caused by the brain, that consciousness arises from the brain. But I think there can be subtle problems with cause and effect. Cause and effect are often different things. So even if consciousness does arise from the brain, it isn't at all clear that consciousness must therefore be reducible to the brain. One must keep these two separate domains distinct, even if interwoven, in their fundamental natures.

ROBERT: A summary question: Fast forward a hundred years. What has happened to consciousness?

JOHN: In a hundred years, and I hope before that, we're going to know how the brain does it. As we talk here, there are very confident people working on precisely this question: By what processes, exactly, do human and animal brains cause consciousness--and I think we're going to know the answer to that.

MARILYN: We'll recognize the limits of a strictly physical, materialist model. We'll have begun to embrace some of the expanded aspects of our being so that we can grapple with the serious social problems that we're facing today.

JIM: I think we'll understand the brain in terms of neurons, and we'll understand how this phenomenon of consciousness arises from that.

ROBERT: Fred, I hope you don't agree with these guys.

FRED: Well, I don't entirely disagree, bit I'll reverse it. What we're going to understand in a hundred years is possibly how consciousness creates brains! And how brains arise from the messiness of reality.

DAVE: I think we'll be closer to creating a sort of fundamental principle connecting physical processes and processes of conscious experience. When we have a simple set of fundamental principles--like the laws of physics--then we'll have a theory of consciousness.

ROBERT: CONCLUDING COMMENT

YOU are not a zombie, and you know it. What it means to be conscious directly affects what it means to be human. The strongest current theory is that consciousness is a complex, emergent property of the brain--a property not easily, or perhaps not ever, reducible to simple states of the brain. This means that consciousness "emerges" from all the complex electrical and chemical activities in our brains, something like an atomic bomb "emerges" from a critical mass of uranium or a molecule of water "emerges" from two atoms of hydrogen and one atom of oxygen. So while consciousness is produced by the brain, we may never know quite how. But I can't shake the thought that consciousness may also be something else--a more fundamental description of self-aware beings like us, a special part of reality.
With philosophers and physicists disagreeing among themselves, it is good that consciousness studies is becoming a scientific field of great promise. For now, this divergence of opinion is what brings us closer to truth.

Editor's Comments:

Reductive materialists "just don't get it." They presume incorrectly that reverence for the Scientific Method dictates a reductive materialist worldview in which only physical matter is "real." They insist incorrectly that consciousness, specifically human consciousness, is somehow "unreal," and does not qualify as scientific data worthy of systematic study. When reductive materialists do this they commit a glaring scientific, not to mention philosophical blunder.

By treating "physical" as a synonym for "real" and dismissing consciousness as "unreal," reductive materialists are guilty of defining consciousness out of existence via semantic sleight of hand. If in order to be considered "real" something must be physical, then anything non-physical will automatically be classified as "unreal." By asserting in advance what they are obligated to prove, reductive materialists are being flagrantly unscientific. In mathematics this is referred to as "begging the question," and constitutes a serious error in logic.


Genuine science deals with reality. Reality is that which exists. Matter exists, but so does consciousness. Since consciousness exists, it is real. Since it exists, it is not "unreal." When one experiences a gut-wrenching anxiety, a heart-rending emotional loss, a conceptual breakthrough, or a flash of spiritual insight, that feeling, that emotion, that thought, that insight exists. It is not "nothing." It is real. Consciousness is not the same as matter of course. Consciousness is different from matter. But that does not make consciousness "unreal," it merely makes it different. It merely makes it another component of reality.

Many "scientifically-minded" Western rationalists still do not grok certain simple yet ancient truths: The soul is real. The mind is real. The spirit is real. These truths were understood millennia ago by great sages such as Sakyamuni and Laozi. The soul, the mind, the spirit can neither be defined out of existence nor reduced to mere matter. Not even gray matter in the brain.

-- Bevin Chu

Explanation: What Is Consciousness?
Illustration(s): David Chalmers, John Searle, Marilyn Schlitz, James Trefil, Fred Alan Wolf, Robert Lawrence Kuhn
Author(s): Dr. Robert Lawrence Kuhn
Affiliation: CLOSER TO TRUTH (CTT)
Source: http://www.closertotruth.com/topics/mindbrain/107/107transcript.html
Publication Date: N/A
Original Language: English
Editor: Bevin Chu, Registered Architect