If you wonder where the sounds and sights in the skull-sized infinite kingdom that is your mind come from, who else can experience the world (dogs, mice, flies, bacteria, matter itself), whether brain organoids, digital computers or sophisticated cyborg can ever be conscious, the (im)-possibility of mind-uploading, and related themes, The Feeling of Life Itself – Why Consciousness is Widespread But Can’t be Computed this short book is for you.

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 an 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 material 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, published by MIT Press (2019), 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 today in the clinic and the laboratory: 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 very 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 has allowed clinicans 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 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 myth 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!

Three reasons for why you may want to read this book.

Firstly, our experience of the world, our thoughts, memories, dreams, desires and fears, arise from the brain, the organ of our mind. In a very real sense, “you” are your brain. Therefore, the better we understand this organ, the better we know ourselves.

Secondly, we all struggle in our daily life – we are overly anxious, we are hooked to social media and compulsively consult our phone every few minutes, we seek equanimity within chaos, we constantly compare ourselves to others and come up short, we struggle with weight, alcohol, drugs and so on. The better we understand our brains, their quirks and idiosyncrasies, and how they evolved to make us the dominant species on the planet, the more likely we can harness our brain power in service of a less stressful and more mindful life. 

Finally, the 21. century will be the time when we begin to take control of our own brains to not only restore function lost to accidents or disease, but also to enhance the working of the healthy brain using brain-computer interfaces or direct brain-to-brain communication. While this is science fiction today, such a future is approaching faster than most think.

The New Scientist, The New Yorker and Prospect Magazine published reviews of the book for a general audience. Here are three more technical reviews, in specialty journals, by Matthew Owen (Philosophia Christi), Talis Bachmann (Journal of Consciousness and Cognition) and Philip Goff (American Journal of Psychology).