My book, The Feeling of Life Itself – Why Consciousness is Everywhere But Can’t be Computed, will be published by MIT Press in the fall of 2019. If you wonder where the sounds and sights in the skull-sized infinite kingdom that is your mind come from, who else has these feelings and whether computers can ever be conscious, this is the book for you.
I am the Chief Scientist and President of the Allen Institute for Brain Science in Seattle in the Pacific Northwest. My passion is to understand how the cortex that makes up the crown of the brain, the most complex tissue of active matter in the known universe, gives rise to any conscious experience – to the feeling of love, melancholy, pain or pleasure. This is the heart of the ancient mind-body problem.
I’m one of seven billion random deals from the deck of human possibilities—I grew up happily, lived in many cities in America, Africa, Europe, and Asia, a physicist turned neurobiologist. From 1986 until 2013, I was a Professor of Biology and Engineering at the California Institute of Technology in Southern California. I’m a vegetarian cyclist with a soft spot for philosophy and a great love for books, big boisterous dogs, vigorous physical activity, and the outdoors, and a sense of melancholy, living in the twilight of a glorious age.
I experience the world – I see a verdant forest, enjoy the delectable taste of Nutella, am in love or am upset. That’s what consciousness is: any experience, no matter how banal or exalted. But how it is that a physical organ like the brain can give rise to feelings? That seems distinctly odd. Nothing in physics, chemistry or biology prepares us for this seemingly miraculous fact – that certain physical systems can have inner states. That’s the beating heart of the ancient mind-body problem.
Until recently, the only tools to explore the mind were introspection, a relative barren enterprise given that so much of the mind is inaccessible to consciousness, and philosophical armchair speculations. But now there is a growing science of consciousness. We can detect and track the footsteps that any conscious experience leaves in the brain. This is the modern quest for the neural correlates of consciousness, a research program that the molecular biologist and co-discoverer of the double-stranded nature of DNA, Francis Crick, and I articulated many years ago. Much progress has been achieved since then in understanding what regions of the brain are responsible for generating experience, and how the waxing and waning of consciousness over the course of the day and the night is reflected in the underlying brain activity.
The book describes Integrated Information Theory (IIT), a quantitative, rigorous, consistent and empirically testable theory that starts with experience and proceeds to the underlying neuronal mechanisms. “Integrated information” is a mathematical measure quantifying how much any system, no matter how simple or how complex, is determined by its past state and how much it can influence its future, its intrinsic causal power. Any system that has this potential is conscious. The larger the system’s integrated information, referred to by the Greek letter phi (pronounced fi), the more conscious the system is. If something has no causal power upon itself, such as the neural networks that underlying machine learning, its phi is zero. It doesn’t feel like anything to be this system.
Unlike superstrings, the welter of ideas derived from IIT can be tested today: Where in the brain does consciousness arise (answer – in the back of the neocortex)? Only in the brains of humans (extremely unlikely)? What about creatures such as elephants, whales or dolphins with bigger brains than us or monkeys, dogs, mice and other mammals with smaller brains that are, however, similar to ours (they too experience the world)? How low does consciousness go in the animal kingdom – what about flies or worms (we don’t know but based on the complexity of their brain, the theory imputes some conscious experience to them)? What happens if the brain is cut into two, as in a split brain surgery to alleviate epileptic seizures (two conscious minds co-exist within the same skull, each one within its own cortical hemisphere)? What happens if two brains are connected together artificially (the two conscious minds would merge into one)? How active is the brain of a long-term meditator in a state of “pure experience” (possibly very little)?
The theory has practical consequences as it allows us to build a consciousness-meter, a practical device that determines whether patients unable to signal by speech, hands or eye movements, either because they are anesthetized or because their brains are severely injured are conscious or not. This method, dubbed zap-and-zip, is now being evaluated in patients and in animal experiments at a number of clinical centers in the US and in Europe, including here at the Allen Institute.
The book squarely addresses the burning question of our times – could appropriately programmed computers be conscious? Could Alexa or Siri 10.0 feel like something?
No! Despite the near-religious belief of the digerati in Silicon Valley, most of the media and the majority of Anglo-Saxon computer and philosophy departments, there will not be a Soul 2.0 running in the Cloud. Consciousness is a not a clever hack. Experience does not arise out of computation.
The dominant mythos of our times, grounded in functionalism and dogmatic physicalism, is that consciousness is a consequence of a particular type of algorithm the human brain runs. According to integrated information theory, nothing could be further from the truth. While appropriate programmed algorithms can recognize images, play Go, speak and drive a car, they will not be conscious. Even a perfect software model of the human brain will not experience anything, because it lacks the intrinsic causal powers of the brain. It will act and speak intelligently. It will claim to have experiences, but that will be make-believe. No one is home. Intelligence without experience.
That’s the difference between the real and the artificial. A supercomputer simulating a rain storm won’t cause its circuit boards to become wet. Nor will a computer simulating a black hole twist and warp space-time around its chassis; you won’t be sucked into its simulated massive gravitational field. It’s the same with consciousness – clever computer programming can simulate the behavior that goes hand-in-hand with human level consciousness but it’ll be fake consciousness.
That’s not to say there is something magical about brains; they are a piece of furniture of the universe like any other. However, brains are by far the most complex chunk of active matter in the known universe. A computer could acquire human-level consciousness but it would have to be built in the image of the human brain, including its vast complexity, so called neuromorphic computers.
Consciousness is fundamentally about being, not about doing. This has a host of scientific, philosophical and ethical consequences.
Stemming in part from a long-standing collaboration with my long-time mentor and close colleague, the late Nobel Laureate Francis Crick, I previously wrote Consciousness: Confessions of a Romantic Reductionist. This thin book blends science and memoir to explore topics in the science of consciousness. My previous textbooks are The Quest for Consciousness: A Neurobiological Approach (2004) and Biophysics of Computation: Information Processing in Single Neurons (1999).
My research interests include elucidating the biophysical mechanisms underlying extracellular electric fields, the computations carried out by cortical neurons, clarifying the structure and function of the claustrum, a thin layer of neurons underneath cortex to which it is strongly and reciprocally connected, and using integrated information theory to study consciousness in brains and machines.