by Heidi Norman
As a physicist, Kaku works a lot with models. His job consists of abstracting various chunks of the world and compressing them into cogs in a grander equation. A model, if it is good, should neatly predict future phenomena.
Kaku sees the mind as essentially a model-making machine. Except that the cogs of consciousness are various parameters of the world, like temperature or position, and the model is used to direct behaviour to accomplish very biological goals like hunting prey, dodging predators and winning a mate. No airy-fairy philosopher stuff like thoughts and experience and free will.
Kaku outlines levels of consciousness that correspond to different degrees of complexity, from the simplest things like plants at Level 0 to we humans on Level III. The big difference with us is that we are self-aware. ‘Human consciousness is a specific form of consciousness that creates a model of the world and then simulates it in time,’ he writes in the book. ‘This requires mediating and evaluating many feedback loops to make a decision to achieve a goal.’
There’s something appealingly tractable about Kaku’s theory, particularly for a cynical philosopher who’s often up to his neck in qualia – a word for when words fail to describe the indescribable features of conscious experience, like trying to describe the redness of a red rose or the ache of new love. But I can’t help but think that his is a theory of cognition, not a theory of consciousness. It describes the information processing that goes into producing behaviour, which is undoubtedly the chief function of the brain, but it doesn’t seem to account for the fact that all this model making coincides with a supremely subjective experience. As the American philosopher Thomas Nagel put it in the 1970s, there’s something it feels like to be a conscious being.
David Chalmers, Director of the Centre for Consciousness at the Australian National University in Canberra, puts it a different way. He draws a distinction between what he called the ‘easy problem’ of consciousness, which is explaining how electrical impulses racing through a network of neurons can produce behaviour, and the ‘hard problem’, which is explaining how on Earth that network can ever produce something like the redness of red. Chalmers imagines a being that does all the information processing we do, and which can make the kinds of decisions we make, but doesn’t have any conscious experience, no ‘qualia’. If such a being is at all possible, then it suggests a complete theory of the mind needs to talk about more than just information processing and brains. It needs to talk about conscious experience too.
I ask Kaku about the conspicuous absence of consciousness in his theory and he hastens to dismiss the problem, borrowing another analogy from science. ‘It used to be that the question of “what is life?” dominated and paralysed biology for decades. Now the question is irrelevant. We now know there are gradations – we have different kinds of viruses, different forms of life. So biologists no longer ask the question “what is life?”, because it turned out to be many layers of a continuum.
‘It’s the same thing about “what is redness?”, “what is a sunset?”, “what is a sensation of ecstasy and thrill?” or “what are qualia?”. Today that absorbs a lot of philosophers’ attention, but I think that just like “what is life?”, that will disappear.’
His counterpoint to Chalmers’ thought experiment of a thinking being without qualia is a thought experiment of his own. One day, he muses, ‘we will have a robot that understands red in ways a hundred times richer than any human. We will have a robot that can tell us the electromagnetic spectrum of red, that can give you all the sensations of red for different kinds of animals, a richness of red far beyond any human’s. And then the robot will say, “do humans understand red?”, and it will say, “obviously not”.’
I’m not sure Chalmers would be convinced the existence of this robot would mean we’ve solved the hard problem, but that’s a philosophical conundrum Kaku is confident will simply fade in time. Not that he’s taking a swipe against philosophy, as theoretical physicists have been apt to do, ‘Steven Weinberg, Nobel Prize winner, wrote a book [Dreams of a Final Theory], and he had a chapter against philosophy. He basically denounced philosophers for putting us on the wrong track, giving us dead ends, and conundrums and paradoxes that were really just plays on words. But after reading that chapter you realise: this is the deepest philosophy of all. So simply by attacking philosophy, you become the enemy. You become a philosopher.’
Indeed Kaku points out that philosophy-bashing physicists really are treading on thin ice, ‘quantum mechanics is perhaps the most philosophical of all sciences’.
Like philosophy, quantum mechanics is rife with conjectures about how the world might be. Maybe there’s just one universe or perhaps a multiverse of countless others, but there’s a lack of the concrete evidence that tells us which of these conjectures, if any, is true.
Nevertheless Kaku maintains his characteristic optimism that physics will ultimately prove its theories. ‘In my years as a physicist I’ve noticed that sometimes experiment and theory chase each other,’ he says. ‘When I was a kid, the strong force gave us thousands of sub-atomic particles. J. Robert Oppenheimer, the father of the atomic bomb, said that the Nobel Prize in Physics should go to the physicist who does not discover a new particle this year. We were drowning in data, but we had no theory. Most of my career was spent in that kind of climate. Now it’s flipped,’ he says.
‘Now, we have the theory of the strong nuclear force, it’s called quantum chromodynamics. And we have theories of quantum gravity. All of a sudden the theory has outraced the data. But does that mean the theory is wrong? No! It just means that we humans are limited by what our gross domestic product can create in terms of atom smashers. It has nothing to do with the correctness or incorrectness of string theory.
‘The difference between physics and philosophy is that string theory is testable, believe it or not.’
This gives a hint as to why Kaku chose to write a book about the mind right now. After centuries of armchair speculation and coarse poking and prodding, finally physicists have gotten involved and brought their rigour – and their tools – to the field. They invented the new gizmos that are opening a window into the brain: magnetic resonance imaging, positron emission tomography, electroencephalography, computed tomography, magnetoencephalography and transcranial magnetic stimulation, to name but a few. ‘In the last ten years we’ve learned more about the brain than in all of human history combined. And it’s all because of physics,’ says Kaku.
His book is filled with tales of scientists watching people’s ‘thoughts’ on a computer screen – of moving objects with the power of the mind – and transmitting one person’s ideas to another. And the most remarkable feat according to Kaku? ‘As I was writing the book last year, the announcement was made at Wake Forest University and University of Southern California in Los Angeles that they’d been able to record a memory and upload that same memory. This is incredible. I was saying that very soon we’ll have that capability, and they did it as I was writing that chapter!’
Kaku envisages a world where our new insights into the workings of the brain enable (almost) unbelievable feats. We will enhance our intelligence to super-Einsteinian levels. We will encode the billions of connections in our brains and upload that information into computers, effectively hitting ‘CTRL-S’ on our personalities and consciousness (whatever the latter is). We will beam that information to other planets via laser, loading our minds into robots on the other end to explore the cosmos like a legion of sentient Mars rovers. There’s nothing in the laws of physics that explicitly says we can’t do any of these things, so they simply become engineering problems.
Of course, if the mind is nothing more than information and physical processes, that means we can create artificial minds as well, although Kaku acknowledges we’re still decades away from building a Level III mind that can think like us.
‘We made a mistake 50 years ago,’ he says. ‘The mistake was to assume the brain is a computer. So what is the brain? The brain is a neural
network of some sort. It’s a learning machine. It rewires itself after mastering a task. Your laptop today is just as stupid as it was yesterday. Your laptop never gets smarter, but brains do. That’s why it’s so hard to create machines that can mimic the brain.’
Naturally, he’s confident it can be done, it’s only a matter of time and money. Which is probably a good thing, because if we create something that has a Level III mind – something that thinks, desires and that can reproduce like we do, something that competes with us for resources – well, we’ve all read enough science fiction to know how that plays out. But Kaku’s not perturbed.
‘First of all, robots are not going to take over any time soon. They have the intelligence of a cockroach – a retarded, lobotomised, stupid, idiotic cockroach. They can barely walk across the road.
‘But I assume in the coming decades they will be as smart as a mouse, then as smart as a rabbit, then as smart as a cat, a dog and eventually – maybe by the end of the century – a monkey. I think at that point they are potentially dangerous so we’ll put a chip in their brain – a fail-safe button – so we can just shut off these monkey-like robots if they start to get too intelligent for their own good.’
But then there’s the question of what to do when they go beyond simian intelligence? What if they become smarter than us? Again, Kaku’s infinite optimism means he’s unperturbed by the prospect of super-intelligent robots roaming around eyeing our stuff. ‘What do we do? We merge with them,’ he says. ‘Otherwise they could literally become smarter than us, put us in zoos and throw peanuts at us.’
Let’s just hope they want to be merged with.
There can be little question that Kaku’s is an extraordinary mind. But it’s also the mind of a physicist. So it’s entirely natural he would look at the mind firmly through the lens of the physical. And there is certainly a part of me that is enticed by his infectious confidence in physics. However, I still can’t quite shake my doubts that even the most penetrating brain scanner will ever truly lay bare the deepest mysteries of consciousness. Then again, after centuries of abstract speculation by philosophers, perhaps Kaku’s refreshingly concrete approach is precisely what we need to unravel the secrets of this extraordinary thing we call the mind.
I, wormbot: The next step in artificial intelligence
It’s all in your mind: The feeling of ‘wetness’ is an illusion
How I rescued my brain
Advisory panel
PROFESSOR CARLA CATTERALL is based at Griffith University, where she teaches ecology and environmental management, and investigates how free-living plants and animals respond to habitat change, and how they might be encouraged to persist within landscapes used by people. Her findings are published in scientific journals and in other formats for land managers and the wider community. Carla is a previous president of the Ecological Society of Australia and recipient of the Serventy Medal for ornithological research.
PROFESSOR MERLIN CROSSLEY is Dean of Science at the University of New South Wales. He studied at the Universities of Melbourne and Oxford (as a Rhodes Scholar) and has carried out research on genetic diseases at Oxford, Harvard, Sydney and UNSW. He serves on the Trust of the Australian Museum, the Boards of the Sydney Institute of Marine Science, the Australian Science Media Centre, NewSouth Innovations and UNSW Press Ltd. He is an enthusiastic science communicator.
PROFESSOR TANYA MONRO is Deputy Vice Chancellor: Research and Innovation and an ARC Georgina Sweet Laureate Fellow, University of South Australia. Tanya received the Bragg Gold Medal (best Physics PhD in Australia) and a Royal Society University Research Fellowship, at the University of Southampton. She served as Inaugural Director: Institute for Photonics and Advanced Sensing, and the ARC Centre of Excellence for Nanoscale BioPhotonics, University of Adelaide. Tanya’s numerous awards include: South Australia’s ‘Australian of the Year’, Scopus Young Researcher of the Year, South Australian Scientist of the Year, and the Malcolm McIntosh Prize for Physical Scientist of the Year.
PROFESSOR ANDY PITMAN is a Professor in climate science at the University of New South Wales. He is the Director of the ARC Centre of Excellence for Climate System Science. His expertise is in climate modelling, with broad interests extending across climate change, climate impacts and land cover change. He has worked extensively on how land cover change and increasing greenhouse gases change the probability of extremes. He has been a lead author on the Intergovernmental Panel on Climate Change and on the Copenhagen Diagnosis. He won the NSW Climate Scientist of the Year in 2010.
Contributors
IDAN BEN-BARAK holds an MSc in microbiology from the Hebrew University of Jerusalem, and a PhD in the history and philosophy of science from the University of Sydney. His first book, Small Wonders: How microbes rule our world, won the 2010 AAAS/Subaru SB&F Prize for Excellence in Science Books, Young Adult category. Why Aren’t We Dead Yet? The survivor’s guide to the immune system, published by Scribe, is his second book. He lives in Melbourne with his wife and two children.
ELIZABETH BRYER is curious about the world and our place in it, and in her short fiction and essays writes about memory, identity and cultural imaginings, as well as the ways in which we are shaped by place, history and politics. She is a commissioning editor for art and literature magazine Higher Arc and is currently working on a novel and essays that combine the mundane with the mythic, as well as translating an award-winning novella. Her online home is
GEORGE CLARK obtained tertiary degrees at Sydney and Stanford Universities followed by an engineering career that included working in Australia, the UK, France, Canada and the USA. He has a small cattle property in the central ranges of NSW where he makes wine and writes poetry, which has been published in several anthologies. He believes it to be a privilege to understand the physical world and the laws of nature to combine with the inexpressible beauty of the natural world.
TRENT DALTON writes for the award-winning The Weekend Australian Magazine. A former assistant editor of the Courier-Mail, he has won a Walkley Award for excellence in journalism, been a four-time winner of the national News Awards Feature Journalist of the Year Award, and was named Queensland Journalist of the Year at the 2011 Clarion Awards for excellence in Queensland media. He was named Features Journalist of the Year at the 2014 and 2013 Kennedy Awards for Excellence in NSW Journalism.
WILSON DA SILVA is a science writer in Sydney, and was for almost a decade the editor-in-chief of Cosmos, the literary science magazine he co-founded. A former science reporter at ABC TV, his writing credits include Nature, The Guardian, The Sydney Morning Herald, The Age, New Scientist and the Australian Financial Review Magazine. He has served as president of the World Federation of Science Journalists, and is the winner of 31 awards, including the AFI for Best Documentary and the Human Rights Award for Print Journalism.
TIM DEAN is a science and technology writer and editor with over 15 years experience. He has edited PC & Tech Authority, Cosmos and Australian Life Scientist magazines, and is currently Section Editor for Science & Technology at The Conversation. He also has a PhD in philosophy, focusing on the intersection between evolution and ethics. With an interest in both philosophy and science, he relished the opportunity to probe quantum physicist Michio Kaku’s thoughts on the nature of the mind.
ELIZABETH FINKEL spent five years at the University of California, San Francisco, studying the genes that transform a mushy egg into a shapely embryo. For the last 20 years she has been a science writer, contributing regularly to the American magazine Science, the ABC Science Show and Cosmos magazine, a popular science magazine that she co-founded and of which she is now Editor in Chief. She has published two books; Stem Cells: Controversy at the Frontiers of Science and The Genome Generation.
LAUREN FUGE is an Adelaide-based author and science communicator. Her debut YA novel When Courage Came to Call was published by Random House Australia in 2010, and her non-fiction has appeared in On Dit, Austral
ian Science, and on her short-form blog,
ALICE GORMAN is a lecturer in the Department of Archaeology at Flinders University, and a member of the Executive Council of the Space Industry Association of Australia. For the last decade, she has focused her research on the archaeology and heritage of space junk and planetary landing sites. Her blog Space Age Archaeology has been archived by the National Library of Australia as a significant scientific publication. She is a regular contributor to The Conversation.
NICK HASLAM is Professor and Head of the School of Psychological Sciences at the University of Melbourne. Nick’s academic work as a social and clinical psychologist has explored psychiatric classification, stigma and intergroup conflict. His books include Psychology in the Bathroom and Introduction to Personality and Intelligence.
JESSE HAWLEY is a lover of science and science communication. He enjoys expressing his passion through fiction and non-fiction, drawing and painting, animation, and any other way he can (including cosmos-themed house parties on Carl Sagan Day). He prefers to write his bios in the third person, but sometimes likes to change it up: to keep up with my science-expounding escapades, you can follow me on Twitter @PenSapiens or my blog,
