Jim Fleming: Consciousness isn't just one of the great mysteries in neuroscience. All sorts of people are slugging it out over their theories about the mind, from philosophers to computer scientists, to theologians. One of the questions that lurks behind the debate over consciousness has cosmic dimensions. Does the mind have an independent existence apart from the brain? Come to think of it, is there any way to answer that question? Steve Paulson figured the best thing to do would be to talk with some of the leading figures in the study of consciousness including neuroscientist Andrew Newberg, philosophers Daniel Dennett and Ken Wilber, physicist Roger Penrose and New Age guru Deepak Chopra. Steve has this report.
Steve Paulson: It's just a three pound chunk of wrinkled tissue, but what a chunk that is. The human brain is so complex it spawned all kinds of competing theories about the nature of consciousness. Some people say science will never explain how the mind works, but others say no, we've been seduced to believe it's far more mysterious than it really is. Take MIT computer scientist Marvin Minsky, one of the pioneers of artificial intelligence. In his book, The Emotion Machine, he argues that part of the problem is the language we use, starting with a word like consciousness.
Marvin Minsky: I call it a suitcase word for about 20 different kinds of mental processes and so whenever you try to explain part of it then you find that you left something out and this makes people feel like there's a big mystery, but I think this is the case with a lot of psychological words.
Paulson: So you're saying that the word consciousness basically doesn't mean anything. It just, it covers so much ground and so many different brain functions that it's just this vague, amorphous concept.
Minsky: That's right. I don't think it's good enough for a scientific word and so we have to replace it by reflection and decisions and about a dozen other things. Once you do that the big problem goes away, and so instead of talking about the mystery of consciousness, let's talk about 20 or 30 really important mental processes that are involved. Then, with a couple of years work you can take a big step towards solving each of them and when you're all done somebody says, well, what about consciousness, and you say, oh that. That was what people wasted their time on in the 20th century.
Paulson: Yet the brain, the human brain, is as far as we know is the most complex object in the whole universe. It contains something like a trillion cells and many synapses. There are many different chemical reactions that go on within the brain. Do you really think computer scientists can understand how all of this works?
Minsky: I can understand exactly how a computer works, although I'm very fuzzy on how the transistors work, and my bet is that when all is done it'll turn out that it didn't matter very much how each synapse worked, so although it's nice to know how all of the individual nerve cells work, what's more important I think is all the middle levels of organization which makes the parts of the brain do things that don't depend very much on the small chemical events inside them.
Paulson: Marvin Minsky believes computer scientists will one day be able to build a copy of the human brain, and, in fact, make a vastly better version of it, but plenty of scientists think it's dead wrong to say the brain works like a computer.
Roger Penrose: It's very different, I mean, subjective experience. There's nothing in science that tells you that such and such a combination of whose-its gives you a subjective experience.
Paulson: Roger Penrose is a renowned British physicist and mathematician. Some years back he felt compelled to launch his own study of consciousness after he heard a radio interview with Marvin Minsky which greatly annoyed him. When Penrose talks about the difficulty of explaining subjective experience he's touching on what philosophers call the hard problem of consciousness, the mysterious nature of our rich inner lives, for instance our experience of love or the quirky dreams we have. He says no computer can generate those experiences, in fact, they're beyond anything that neuroscience, biology, or physics can now explain.
Penrose: We do need a major revolution in our understanding of the physical word in order to accommodate consciousness. The most likely place, if we're not going to go outside physics altogether, is in this big unknown, namely making sense of quantum mechanics. It's the borderline if you like between quantum mechanical behavior and classical behavior. Now this borderline is completely un-understood at the moment.
Paulson: Penrose has a theory about how this quantum computation within the brain might work, which involves tiny protein structures within neurons called micro-tubules. His theory is quite speculative and highly controversial. The late biochemist Francis Crick once said of Penrose, at bottom his argument is that quantum gravity is mysterious and consciousness is mysterious and wouldn't it be wonderful if one explained the other? It will be remarkable if it turns out to be true. Listening to some of these theories makes me wonder if I am wondering aimlessly around my consciousness. Looking for some reassurance I checked in with the philosopher Daniel Dennett who once wrote a book called A Consciousness Explained. Dennett is an unabashed materialist who believes a thorough understanding of the brain's neural structures and electrochemical surges will tell us everything we need to know about the mind.
Daniel Dennett: There's lot of puzzles. There aren't any mysteries. If we distinguish between problems that we haven't yet solved but things that we have at least some leads on, I don't think consciousness is a mystery.
Paulson: But there are all kinds of things that I just, I can't imagine how science will ever be able to explain. For instance, the precise nature of how we love someone else. I mean, I'm not talking about the sex drive here, but I'm talking about the mystery of love, or why we have certain kinds of dreams, and dreams, of course, are not rooted at all in the physical world. I mean, if you dissect the brain somehow and look at all the neural connections, do you think science will ever be able to explain those things?
Dennett: Sure. In what sense of explaining? Would you find it just unimaginable that science might in the next 15 or 20 years be able to read people's brains while they sleep and then write down what they're actually dreaming? Would you give me that kind of mind reading?
Paulson: I don't think I would.
Dennett: We can't do it yet. We can do it a little bit.
Paulson: I don't give you that actually.
Dennett: Well, then hang onto your hat-
Dennett: 'Cause that's coming.
Paulson: So you're saying science will be able to do that without any kind of self-reporting by the dreamer?
Dennett: Oh no. We'll use waking reports by dreamers of course to calibrate the instruments and understand how to decode the neural signals.
Paulson: See, that's my point. That's my point. If you don't actually ask the person what they're dreaming will you ever be able to decipher the dreams?
Dennett: Well, let's build up to it then. So, we ask the person what they're dreaming for 100 nights and we build up a nice library and we translate the relevant brain states for that person, then the idea that one might be able to say a little bit later, oh, look, look, Jones is having that dream about the old car and look, he's falling over a cliff now, and we wake him up and that's what he reports. If you think that's just beyond the reach of science I think you're wrong.
Paulson: But that's just correlation, you're just, you know-
Dennett: That's right.
Paulson: You're just looking at what so-and-so has dreamed and you're just going to match the brain imaging to some future dream. That still doesn't explain how within the brain that particular kind of dream is generated.
Dennett: So, we have to do that too, but I think we're making good progress on that too. We can't do that now. Might we do that in the future? Certainly.
Paulson: Ken Wilber is a very different kind of philosopher. Unlike the reductionism of Dan Dennett, Wilbur embraces what he calls an integral philosophy, a theory of consciousness within an explicitly spiritual dimension. He says a materialist understanding of consciousness simply doesn't get you anywhere.
Ken Wilber: If you're looking at just material stuff like a planet that doesn't have life on it, or a rock, a physicist can tell you where that planet's going to be, barring other forces 1,000 years from now, but that physicist cannot tell you were my dog's going to be two seconds from now.
Paulson: Ken Wilber's heady mix of eastern spirituality and wide-ranging analytical thinking has given him an almost cult-like following. He regards consciousness as interior experience which is quite distinct from the neural circuitry of the brain. That position sets him apart from virtually every neuro-scientist, but Wilber says we'll never be able to explain the mind just by looking at it's physical make-up.
Wilber: It reduces everything. I mean, if that's the case, then you're statement itself and your awareness is nothing but neuro-chemical fireworks and you can make no distinctions of value. There is no such thing as love is better than hate. All those value distinctions are erased.
Paulson: You can't make the value distinctions, but is there still anything to say that that scientific view is wrong?
Wilber: Well, at this point, of course you've entered the philosophy of science, and the argument is endless. Is there nothing but physical stuff in the universe, or is there some sort of interiority? Not, we're not talking about ghosts and goblins and souls, all that good stuff. Just is there interiority? Is there an inside to the universe? If there is interiority as there is exteriority then that interiority is where consciousness resides and where values reside and you can't see that, but it's real.
Paulson: So, where does religion fit in this whole business? Can we actually see God in the brain? Well, not exactly, but Andrew Newberg, a neuroscientist at the University of Pennsylvania, can pinpoint the precise parts of the brain that are activated during religious experience. By using brain scanning technology he's found that meditating Buddhist monks and praying Franciscan nuns have remarkably similar cognitive experiences. In both cases the parietal lobe shuts down which leads to a loss of the sense of self creating that feeling of oneness with the universe that mystics so often describe. The difference is that the nuns activate the language parts of the brain while the Buddhists stimulate their visual areas. Still, these studies beg the question, do these altered states of consciousness result from an encounter with God or some larger intelligence, or is it just an electrochemical surge firing in the brain? Newberg himself doesn't know.
Andrew Newberg: We don't know if it's something that just comes out of the brain that we then experience as coming from outside of us as if it was a hallucination like what would happen in schizophrenia or whether it really is something that's out there that somehow touches our senses and our experiences or whether it's something that's purely internal and yet still enables our brain to rest on some more fundamental plane of reality or existence.
Paulson: There are clear religious implications to this whole mind-brain conundrum. Think about it. If your mind can communicate with God, or if there really is life after death then consciousness must go beyond the purely physical mechanics of the brain. This is why this whole question of consciousness is the whole 800 pound gorilla looming over the whole science and religion debate. It's why most, though not all, Atheists line up on the side of materialism, while religious believers assume the mind is more than the brain, but even some Atheists admit that consciousness is a great mystery.
Richard Dawkins: Consciousness is the biggest puzzle facing biology, facing neurobiology, facing evolutionary biology. It is a very, very big problem.
Paulson: That's the famous Oxford biologist and outspoken Atheist Richard Dawkins, author of The God Delusion.
Dawkins: I don't know the answer. Nobody knows the answer. I think they probably one day will know the answer, but even if science doesn't know the answer I return to the question, what on Earth makes you think that religion will? To say that because science has so far failed to explain something such as consciousness that therefore the facile, pathetic explanations religion has produced somehow by default must win the argument really is quite ridiculous. We don't have an explanation. Nobody has an explanation for consciousness. That should be a spur to work harder and try to understand it, not to give up and say, oh well, it must be a soul. You said absolutely nothing when you said that.
Paulson: Deepak Chopra is about as far as you can get from Richard Dawkins. Chopra is the best-selling New Age guru famous for touting mind-body healing and Hindu spirituality, but Chopra is also well-versed in some of the cutting edge but highly speculative theories about consciousness which tend to rely on the weirdness of quantum physics like the principle of non-locality where particles nowhere near each other in space can affect each other and how the active observation can actually create the phenomenon that are observed. In his book, Life After Death, Chopra argues that there's plenty of scientific support for the idea that consciousness doesn't really end with death.
Deepak Chopra: Well, all we have to understand is what comes first. Does consciousness come first or magic comes first? The old paradigm was that consciousness is a phenomenon of molecules, but now, we know that molecules are only atoms. Atoms are subatomic particles and that these subatomic particles are fluctuations of energy and information in a huge void, and the void is not emptiness. It's the womb of creation.
Paulson: OK. My head is starting to spin. I confess, I'm getting lost in the theoretical possibilities of the new physics and what this might mean for some cosmic consciousness, so I turn to America's best-known Atheist, Sam Harris, whose book, The End of Faith, has become a kind of touchstone for lots of skeptics. Harris is the most viscous critic of religious belief I've ever read, so what's his take on this question? Can consciousness survive death?
Sam Harris: I just don't know. One thing I can tell you is that we don't know what the actual relationship between consciousness and the physical world is.
Paulson: What makes Sam Harris so compelling on the question of consciousness is his background. He's getting his PhD in neuroscience. What's more, he spent years practicing Buddhist meditation. So, Harris is not your garden-variety Atheist, which makes his take on consciousness and life after death all the more fascinating.
Harris: There are good reasons to be skeptical of the naive conception of the soul, and so the idea the brain can die and a soul that still speaks English and recognizes granny is going to float away into the afterlife, that seems to be profoundly implausible. Yet, we do not know what the relationship between subjectivity and objectivity ultimately is and, for instance, we could be living in an universe where consciousness goes all the way down to the bedrock so that there is some interior subjective dimension to an electron say.
Paulson: That's interesting, though, because most evolutionary biologists, some in particular, thinking that the secular ones would say, of course, consciousness cannot survive the brain. It will not survive death. You are not willing to make that claim.
Harris: Yeah. I just don't know. I'm just trying to be honest about my degradations of certainty. If we were living in a universe where consciousness survived death in some sense, or just transcended the brain so that single neurons were conscious we would not expect to see it by our present techniques of neuro-imaging or cellular neuroscience and we would never expect to see it. There are profound philosophical and epistemological problems that anyone must confront whose trying to reduce consciousness to the workings of the brain and this discourse is in its infancy and who knows where it's going to go.
Paulson: To me, those comments from Sam Harris pretty much sum up the whole murky question of consciousness. Oh, there's one other thing. Maybe our obsessive self-awareness and human consciousness itself really isn't all it's cracked up to be.
Fleming: Steve Paulson prepared that report.