Publisher's Weekly Review
Seth (Eye Benders), professor of neuroscience at the University of Sussex, takes on the prodigious task of defining consciousness and explaining its origins in this intense survey. His goal is "to understand how the inner universe of subjective experience relates to, and can be explained in terms of, biological and physical processes unfolding in brains and bodies." To that end, he breaks down the neuroscience, psychology, and a hefty dose of philosophy, as well as his own research, to conclude that rather than perceiving reality, "we're all hallucinating all the time. It's just that when we agree about our hallucinations, that's what we call reality." Consciousness is all about human bodies, in an attempt to survive, using their senses to predict how the world is constructed and likely to change; he argues he thus views perception as a creative act. Seth explores consciousness in nonhuman animals (they have it, he writes: "consciousness has more to do with being alive than with being intelligent") and the probability that it might arise via artificial intelligence, a prospect that he deems unlikely. A slew of terms and theories are introduced that may be difficult to get through for readers without a neuroscience background. But those who stay the course will find much to consider. Agent: PJ Mark, Janklow & Nesbit Assoc. (Oct.)
Guardian Review
For every stoner who has been overcome with profound insight and drawled, "Reality is a construct, maaan," here is the astonishing affirmation. Reality - or, at least, our perception of it - is a "controlled hallucination", according to the neuroscientist Anil Seth. Everything we see, hear and perceive around us, our whole beautiful world, is a big lie created by our deceptive brains, like a forever version of The Truman Show, to placate us into living our lives. Our minds invent for us a universe of colours, sounds, shapes and feelings through which we interact with our world and relate to each other, Seth argues. We even invent ourselves. Our reality, then, is an illusion, and understanding this involves tackling the thorny issue of consciousness: what it means to, well, be. Consciousness has long been the preserve of philosophers and priests, poets and artists; now neuroscientists are investigating the mysterious quality and trying to answer the hard question of how consciousness arises in the first place. If this all sounds a bit hard going, it's actually not at all in the masterly hands of Seth, who deftly weaves the philosophical, biological and personal with a lucid clarity and coherence that is thrilling to read. Consciousness, which Seth defines as "any kind of subjective experience whatsoever", is central to our being and identity as animate sentient creatures. What does it mean for you to be you, as opposed to being a stone or a bat? And how does this feeling of being you emerge from the squishy conglomeration of cells we keep in our skulls? Science has shied away from these sorts of intrinsically experiential questions, partly because it's not obvious how science's tools could explore them. Scientists are fond of pursuing "objective" truths and realities, not probing the perspectival realms of subjectivity to seek the truth of nostalgia, joy or the perfect blueness of an Yves Klein canvas. Also, it's hard. Seth might use other words, but essentially, he is exploring the science of people's souls - a daunting task. All of this, of course, makes consciousness one of the most exciting scientific frontiers, and nobody is better placed to guide us there. Seth has been researching the cognitive basis of consciousness for more than two decades and is an established leader in the field. He has pioneered new ways of analysing the inscrutable and measuring the incalculable in his quest to deduce the constituents of our feelings down to their atomic basis. This much-anticipated book lays out his radical theory of our invented reality with accessible and compelling writing. We take for granted the idea that we journey through life, inhabiting a world that's really out there, as the starring character in our own biopic. But this hallucination is generated by our minds, Seth explains. The brain is a "prediction machine" that is constantly generating best-guess causes of its sensory inputs. The mind generates our "reality" based on the predictions it makes from visual, auditory and other sensory information, and then constantly verifies and modulates it through sensory information updates. "Perception happens through a continual process of prediction error minimisation," he writes. These perceptual expectations shape our conscious experience. When we agree with each other about our hallucinations we call it "reality"; when we don't we're described as "delusional". Sometimes these disagreements can help us to peek past what William Blake called the "doors of perception". One of these discombobulating events that you may have experienced was #TheDress: an overexposed photo posted on social media in 2015, in which a striped dress looked blue and black to some people, and white and gold to others. The version that people saw depended on whether their brain had taken into account an adjustment for ambient lighting when generating their reality. People who spent more time indoors were more likely to see the dress as blue and black, because their prediction machine was primed to factor in yellowish lighting when preparing the hallucination. Those who spend more time outside have brains primed to adjust for the bluer spectrum of sunlight. The dress phenomenon, Seth argues, is "compelling evidence that our perceptual experiences of the world are internal constructions, shaped by the idiosyncrasies of our personal biology and history". In objective, non-hallucinated reality, though, the dress doesn't have physical properties of blueness, blackness, whiteness or goldness. Colour is not a physical property of things in the way that mass is. Rather, objects have particular ways that they reflect light that our brains include in their complex Technicolor production of "reality". "We perceive the world not as it is, but as it is useful to us," Seth writes. In other words, we evolved this generated reality because operating through our hallucinated world improves our survival, by helping us avoid danger and recognise food, for example. This is still an emerging science and Seth is generous to his fellow navigators, including those with competing theories, as he gently and persuasively walks us through the optical illusions, magic tricks and fascinating experiments that build his case. We are, his research shows, much more likely to perceive things we expect. In a study in which people were shown brief flashes of different images in their left and right eyes, hearing a cue for an image meant they were much more likely to "see" that image yet be unconscious of the competing image shown to the other eye. Sometimes, our hallucinated world is wildly out of sync with everyone else's - we lose our grip on reality. "What we call a 'hallucination' is what happens when perceptual priors are unusually strong, overwhelming the sensory data so that the brain's grip on their causes in the world starts to slide." Seth has experimented with shifting his own reality - he describes using virtual reality headsets and taking LSD. I learn to my surprise that hallucinogens really do take you to a higher level of consciousness - your amount of consciousness can now be measured independently from wakefulness. This has had life-changing consequences, Seth explains, enabling "locked-in" patients to be recognised as conscious, despite their apparently inert state. What then is the ground zero of consciousness in a living being - or indeed, an artificial one? At its most fundamental, it's an awareness of self, knowing where you end and the rest of the world's matter begins, and Seth explores a diversity of self-perception from parrots to octopuses - whose suckers attach to almost everything but their own skin, because they can taste themselves. He interrogates self-knowledge from inside out, dismantling the idea that our emotions produce bodily expressions, such as tears. Instead, Seth argues, our emotions are a response to the mind's perception of our bodily reactions: we are sad because we perceive ourselves to be crying. Likewise, we are fearful because we perceive our heart is beating faster - a survival mechanism to ready us to respond to a threat picked up by the visual cortex, for instance. Our feelings, even much of our experience of free will, are also hallucinations issued by the mind to control ourselves. The self, then, is another perception, a controlled hallucination built up from an assemblage of perceptual best-guesses, prior beliefs and memories. Seth writes movingly of his mother's episodes of hospital-induced delirium and delusions, and recounts the story of a talented musicologist who suffered catastrophic memory loss. The loss of memory, Seth explains, disrupted the continuity of his self perception - his "narrative self" - eroding his personal identity. We perceive ourselves to control ourselves, is Seth's often counterintuitive but nevertheless convincing argument in this meticulously researched book. However, we are just as importantly the perception of others. Seth mentions just briefly that we modulate our behaviour in response to our perceptions of what others may be thinking about us, but the social context of our "self" is far more important than that. We are to a great extent the invention of others' minds. Being you, after all, is not just about the sentience you experience, but also the youness of you. By the time my beloved grandfather died of a stroke in 2012, I'd already grieved for him for two years. Dementia had taken a smart, funny, gentle man and left us with a stranger, who lashed out or spoke inappropriately and unkindly. He was clearly somebody - he was fully conscious - but he was not himself. It is we who, bereft of his advice and conversation, knew who we'd lost - and with it, something of ourselves. That said, Being You is an exhilarating book: a vast-ranging, phenomenal achievement that will undoubtedly become a seminal text.
Kirkus Review
A neurobiological account of consciousness. "Whether you're a scientist or not, consciousness is a mystery that matters." So writes Seth, a neuroscientist at the University of Sussex. "For each of us, our conscious experience is all there is." Some current theories make the mystery all the more mysterious: the notion, for example, that consciousness is a shared hallucination, a thought that would send a Cartesian into fits. What matters, by Seth's account, is that consciousness arises in the "wetware" of our brains, which "are not computers made of meat" but are instead assemblages of electrical and chemical networks that, crucially, are embodied--i.e., contained within a living being. "In my view," writes the author, "consciousness has more to do with being alive than with being intelligent." That said, he depicts the brain as a marvelous thing that we only dimly understand but that has provoked tremendous scientific growth in recent years. In one moving episode, Seth scrubs in for an eight-hour neurological operation that, by exposing the brain to surgical intervention, revealed "the mechanics of a human self." Exploring the nature and content of consciousness, the author finds it intricately linked with self-consciousness. He also emphasizes its biological nature, suggesting that biotechnology, more than the "fleshless calculus" of artificial intelligence, will bring us further advances into what he calls "synthetic consciousness," teaching machines to think in more human terms. As for human consciousness proper, it works by means of perception. We perceive the passage of time, and it passes; we perceive the world, and it exists. These are testable notions, he asserts, that help place us in the world and in time, allowing us to accept the inevitable, when "the controlled hallucination of being you finally breaks down into nothingness." It may not be the most comforting thought, but there are worse. An accessible, unfailingly interesting look inside the workings of the human brain, celebrating its beguiling nature. Copyright (c) Kirkus Reviews, used with permission.
Excerpts
1 The Real Problem What is consciousness? For a conscious creature, there is something that it is like to be that creature. There is something it is like to be me, something it is like to be you, and probably something it is like to be a sheep, or a dolphin. For each of these creatures, subjective experiences are happening. It feels like something to be me. But there is almost certainly nothing it is like to be a bacterium, a blade of grass, or a toy robot. For these things, there is (presumably) never any subjective experience going on: no inner universe, no awareness, no consciousness. This way of putting things is most closely associated with the philosopher Thomas Nagel, who in 1974 published a now legendary article called "What is it like to be a bat?" in which he argued that while we humans could never experience the experiences of a bat, there nonetheless would be something it is like for the bat, to be a bat. I've always favored Nagel's approach because it emphasizes phenomenology: the subjective properties of conscious experience, such as why a visual experience has the form, structure, and qualities that it does, as compared to the subjective properties of an emotional experience, or of an olfactory experience. In philosophy, these properties are sometimes also called qualia: the redness of red, the pang of jealousy, the sharp pain or dull throb of a toothache. For an organism to be conscious, it has to have some kind of phenomenology for itself. Any kind of experience-any phenomenological property-counts as much as any other. Wherever there is experience, there is phenomenology; and wherever there is phenomenology, there is consciousness. A creature that comes into being only for a moment will be conscious just as long as there is something it is like to be it, even if all that's happening is a fleeting feeling of pain or pleasure. We can usefully distinguish the phenomenological properties of consciousness from its functional and behavioral properties. These refer to the roles that consciousness may play in the operations of our minds and brains, and to the behaviors an organism is capable of, by virtue of having conscious experiences. Although the functions and behaviors associated with consciousness are important topics, they are not the best places to look for definitions. Consciousness is first and foremost about subjective experience-it is about phenomenology. This may seem obvious, but it wasn't always so. At various times in the past, being conscious has been confused with having language, being intelligent, or exhibiting behavior of a particular kind. But consciousness does not depend on outward behavior, as is clear during dreaming and for people suffering states of total bodily paralysis. To hold that language is needed for consciousness would be to say that babies, adults who have lost language abilities, and most if not all nonhuman animals lack consciousness. And complex abstract thinking is just one small part-though possibly a distinctively human part-of being conscious. Some prominent theories in the science of consciousness continue to emphasize function and behavior over phenomenology. Foremost among these is the "global workspace" theory, which has been developed over many years by the psychologist Bernard Baars and the neuroscientist Stanislas Dehaene, among others. According to this theory, mental content (perceptions, thoughts, emotions, and so on) becomes conscious when it gains access to a "workspace," which-anatomically speaking-is distributed across frontal and parietal regions of the cortex. (The cerebral cortex is the massively folded outer surface of the brain, made up of tightly packed neurons.) When mental content is broadcast within this cortical workspace, we are conscious of it, and it can be used to guide behavior in much more flexible ways than is the case for unconscious perception. For example, I am consciously aware of a glass of water on the table in front of me. I could pick it up and drink it, throw it over my computer (tempting), write a poem about it, or take it back into the kitchen now that I realize it's been there for days. Unconscious perception does not allow this degree of behavioral flexibility. Another prominent theory, called "higher-order thought" theory, proposes that mental content becomes conscious when there is a "higher-level" cognitive process that is somehow oriented toward it, rendering it conscious. In this theory, consciousness is closely tied to processes like metacognition-meaning "cognition about cognition"-which again emphasizes functional properties over phenomenology (though less so than global workspace theory). Like global workspace theory, higher-order thought theories also emphasize frontal brain regions as key for consciousness. Although these theories are interesting and influential, I won't have much more to say about either in this book. This is because they both foreground the functional and behavioral aspects of consciousness, whereas the approach I will take starts from phenomenology-from experience itself-and only from there has things to say about function and behavior. The definition of consciousness as "any kind of subjective experience whatsoever" is admittedly simple and may even sound trivial, but this is a good thing. When a complex phenomenon is incompletely understood, prematurely precise definitions can be constraining and even misleading. The history of science has demonstrated many times over that useful definitions evolve in tandem with scientific understanding, serving as scaffolds for scientific progress, rather than as starting points, or ends in themselves. In genetics, for example, the definition of a "gene" has changed considerably as molecular biology has advanced. In the same way, as our understanding of consciousness develops, its definition-or definitions-will evolve too. If, for now, we accept that consciousness is first and foremost about phenomenology, then we can move on to the next question. How does consciousness happen? How do conscious experiences relate to the biophysical machinery inside our brains and our bodies? How indeed do they relate to the swirl of atoms or quarks or superstrings, or to whatever it is that the entirety of our universe ultimately consists in? The classic formulation of this question is known as the "hard problem" of consciousness. This expression was coined by the Australian philosopher David Chalmers in the early 1990s and it has set the agenda for much of consciousness science ever since. Here is how he describes it: It is undeniable that some organisms are subjects of experience. But the question of how it is that these systems are subjects of experience is perplexing. Why is it that when our cognitive systems engage in visual and auditory information-processing, we have visual or auditory experience: the quality of deep blue, the sensation of middle C? How can we explain why there is something it is like to entertain a mental image, or to experience an emotion? It is widely agreed that experience arises from a physical basis, but we have no good explanation of why and how it so arises. Why should physical processing give rise to a rich inner life at all? It seems objectively unreasonable that it should, and yet it does. Chalmers contrasts this hard problem of consciousness with the so-called easy problem-or easy problems-which have to do with explaining how physical systems, like brains, can give rise to any number of functional and behavioral properties. These functional properties include things like processing sensory signals, selection of actions and the control of behavior, paying attention, the generation of language, and so on. The easy problems cover all the things that beings like us can do and that can be specified in terms of a function-how an input is transformed into an output-or in terms of a behavior. Of course, the easy problems are not easy at all. Solving them will occupy neuroscientists for decades or centuries to come. Chalmers's point is that the easy problems are easy to solve in principle, while the same cannot be said for the hard problem. More precisely, for Chalmers, there is no conceptual obstacle to easy problems eventually yielding to explanations in terms of physical mechanisms. By contrast, for the hard problem it seems as though no such explanation could ever be up to the job. (A "mechanism"-to be clear-can be defined as a system of causally interacting parts that produce effects.) Even after all the easy problems have been ticked off, one by one, the hard problem will remain untouched. "[E]ven when we have explained the performance of all the functions in the vicinity of experience-perceptual discrimination, categorization, internal access, verbal report-there may still remain a further unanswered question: Why is the performance of these functions accompanied by experience?" The roots of the hard problem extend back to ancient Greece, perhaps even earlier, but they are particularly visible in RenZ Descartes's seventeenth-century sundering of the universe into mind stuff, res cogitans, and matter stuff, res extensa. This distinction inaugurated the philosophy of dualism, and has made all discussions of consciousness complicated and confusing ever since. This confusion is most evident in the proliferation of different philosophical frameworks for thinking about consciousness. Take a deep breath, here come the "isms." My preferred philosophical position, and the default assumption of many neuroscientists, is physicalism. This is the idea that the universe is made of physical stuff, and that conscious states are either identical to, or somehow emerge from, particular arrangements of this physical stuff. Some philosophers use the term materialism instead of physicalism, but for our purposes they can be treated synonymously. At the other extreme to physicalism is idealism. This is the idea-often associated with the eighteenth-century bishop George Berkeley-that consciousness or mind is the ultimate source of reality, not physical stuff or matter. The problem isn't how mind emerges from matter, but how matter emerges from mind. Sitting awkwardly in the middle, dualists like Descartes believe that consciousness (mind) and physical matter are separate substances or modes of existence, raising the tricky problem of how they ever interact. Nowadays, few philosophers or scientists would explicitly sign up for this view. But for many people, at least in the West, dualism remains beguiling. The seductive intuition that conscious experiences seem nonphysical encourages a "na*ve dualism" where this "seeming" drives beliefs about how things actually are. As we'll see throughout this book, the way things seem is often a poor guide to how they actually are. One particularly influential flavor of physicalism is functionalism. Like physicalism, functionalism is a common and often unstated assumption of many neuroscientists. Many who take physicalism for granted also take functionalism for granted. My own view, however, is to be agnostic and slightly suspicious. Functionalism is the idea that consciousness does not depend on what a system is made of (its physical constitution), but only on what the system does, on the functions it performs, on how it transforms inputs into outputs. The intuition driving functionalism is that mind and consciousness are forms of information processing which can be implemented by brains, but for which biological brains are not strictly necessary. Notice how the term "information processing" sneaked in here unannounced (as it also did in the quote from Chalmers a few pages back). This term is so prevalent in discussions of mind, brain, and consciousness that it's easy to let it slide by. This would be a mistake, because the suggestion that the brain "processes information" conceals some strong assumptions. Depending on who's doing the assuming, these range from the idea that the brain is some kind of computer, with mind (and consciousness) being the software (or "mindware"), to assumptions about what information itself actually is. All of these assumptions are dangerous. Brains are very different from computers, at least from the sorts of computers that we are familiar with. And the question of what information "is" is almost as vexing as the question of what consciousness is, as we'll see later on in this book. These worries are why I'm suspicious of functionalism. Taking functionalism at face value, as many do, carries the striking implication that consciousness is something that can be simulated on a computer. Remember that for functionalists, consciousness depends only on what a system does, not on what it is made of. This means that if you get the functional relations right-if you ensure that a system has the right kind of "input-output mappings"-then this will be enough to give rise to consciousness. In other words, for functionalists, simulation means instantiation-it means coming into being, in reality. How reasonable is this? For some things, simulation certainly counts as instantiation. A computer that plays Go, such as the world-beating AlphaGo Zero from the British artificial intelligence company DeepMind, is actually playing Go. But there are many situations where this is not the case. Think about weather forecasting. Computer simulations of weather systems, however detailed they may be, do not get wet or windy. Is consciousness more like Go or more like the weather? Don't expect an answer-there isn't one, at least not yet. It's enough to appreciate that there's a valid question here. This is why I'm agnostic about functionalism. There are two more "isms," then we're done. The first is panpsychism. Panpsychism is the idea that consciousness is a fundamental property of the universe, alongside other fundamental properties such as mass/energy and charge; that it is present to some degree everywhere and in everything. People sometimes make fun of panpsychism for claiming things like stones and spoons are conscious in the same sort of way that you or I are, but these are usually deliberate misconstruals designed to make it look silly. There are more sophisticated versions of the idea, some of which we will meet in later chapters, but the main problems with panpsychism don't lie with its apparent craziness-after all, some crazy ideas turn out to be true, or at least useful. The main problems are that it doesn't really explain anything and that it doesn't lead to testable hypotheses. It's an easy get-out to the apparent mystery posed by the hard problem, and taking it on ushers the science of consciousness down an empirical dead end. Finally, there's mysterianism, which is associated with the philosopher Colin McGinn. Mysterianism is the idea that there may exist a complete physical explanation of consciousness-a full solution to Chalmers's hard problem-but that we humans just aren't clever enough, and never will be clever enough, to discover this solution, or even to recognize a solution if it were presented to us by super-smart aliens. A physical understanding of consciousness exists, but it lies as far beyond us as an understanding of cryptocurrency lies beyond frogs. It is cognitively closed to us by our species-specific mental limitations. What can be said about mysterianism? There may well be things we will never understand, thanks to the limitations of our brains and minds. Already, no single person is able to fully comprehend how an Airbus A380 works. (And yet I'm happy to sit in one, as I did one time on the way home from Dubai.) There are certainly things which remain cognitively inaccessible to most of us, even if they are understandable by humans in principle, like the finer points of string theory in physics. Since brains are physical systems with finite resources, and since some brains seem incapable of understanding some things, it seems inescapable that there must be some things which are the case, but which no human could ever understand. However, it is unjustifiably pessimistic to preemptively include consciousness within this uncharted domain of species-specific ignorance. Excerpted from Being You: A New Science of Consciousness by Anil Seth All rights reserved by the original copyright owners. Excerpts are provided for display purposes only and may not be reproduced, reprinted or distributed without the written permission of the publisher.
