"Being You: A New Science of Consciousness
By Anil Seth
(Dutton, 340 pages, $28)
Whenever I hear that someone has found a new theory of consciousness, I start to lose my own. The puzzle of how it is that squidgy, physical brains can give rise to primitive sensations, rich emotions and complex thoughts has stubbornly resisted solution; it's not even clear how it could be solved. So when the latest would-be Einstein announces yet another theory, my eyes start to glaze over in anticipation of drivel and disappointment. Neuroscientist Anil Seth's "Being You" is the exception that proves the rule. If you only read one book about consciousness, it must be his.
Most theories of consciousness are doomed to fail because they try to solve the wrong puzzle. What the philosopher David Chalmers has called the "hard problem" is how consciousness could possibly be part of an entirely physical universe. How can the stuff of stones and bones also be the stuff of thought? The other, "easy" problem is how brain activity relates to mental activity -- what the "neural correlates" of consciousness are. This problem is easy only in the sense that it presents no deep conceptual difficulties, just hard empirical lab work.
Following either of these paths leaves researchers between a rock and hard place. No matter how much you discover about the correlations between brain states and mental states, you never explain why it is that any brain state should result in a subjective feeling at all. But if you try to answer the hard problem, you quickly get nowhere.
Mr. Seth argues that if we are to understand consciousness better, we would do well to stop going after the easy or hard problem. Instead he poses the "real problem" of consciousness. It requires that we explain "why a particular pattern of brain activity -- or other physical process -- maps to a particular kind of conscious experience, not merely establishing that it does."
His general answer to the "why" question is that our minds are prediction machines, making informed guesses not only about the world but about what is going on in our own bodies. As he puts it: "The entirety of perceptual experience is a neuronal fantasy that remains yoked to the world through a continuous making and remaking of perceptual best guesses."
If this doesn't sound like an "aha!" moment, that's because it isn't meant to be. Mr. Seth believes that, as we work piece by piece to understand the details of why the mind works as it does, the hard problem will "fade away, eventually vanishing in a puff of metaphysical smoke." The precedent for this is the science of life. For centuries scientists puzzled as to how anything could be alive, imagining there must be some kind of ethereal life force that animates matter. As our understanding of biology progressed, this sense of mystery faded. Similarly, the hard problem of consciousness may not be so much solved as dissolved.
Mr. Seth's understanding of the mind as a prediction machine entails the idea that we don't perceive the world as it is. Rather our perceptions are "controlled hallucinations," designed by evolution to "enhance our survival prospects, not to be a transparent window onto an external reality."
The same is true of our sense of self. "The self is not an immutable entity that lurks behind the windows of the eyes, looking out into the world and controlling the body as a pilot controls a plane," he says. It is rather a hodgepodge of functions that give us the abilities to perceive the world from a point of view, to make decisions, to possess a narrative sense of autobiography and to locate ourselves in society. The feeling that we have that this is all the work of a singular subject is just another controlled hallucination.
Mr. Seth is meticulously precise in his use of language, for the purposes of clarity and rigor. But I'm not so sure that he was wise to use words like "hallucination" and "fantasy." As he says, there is a big difference between normal perceptions when "what we perceive is tied to -- controlled by -- causes in the world" and what we normally call hallucinations, when our perceptions have "lost their grip on these causes." Of course, how the world is in itself and how it seems to us must be different: All perception has to be mediated through the senses. But to call these representations "hallucinations" invites the misunderstanding that we never have a grip on reality at all.
Such minor concerns aside, "Being You" is an impressive work that handles complex issues with exceptional insight and beautiful clarity. Mr. Seth's chapter on free will should be read ahead of any book-length treatment of the subject.
Similarly, his chapter on artificial intelligence cuts through the froth and hype, arguing that fears that conscious AI is just around the corner are based on the false assumption that consciousness and intelligence are intimately linked: "that consciousness will just come along for the ride." It ignores the fact that consciousness is "a deeply embodied biological process."
Mr. Seth argues that "the fuss about machine consciousness is symptomatic of an increasing alienation from our biological nature and from our evolutionary heritage." His book helps to make us more at home with both. It shows how hard-nosed science can also be deeply humane. For all that neuroscience has shattered naive illusions we have about the world, ourselves and our free will, it leaves everything of value in place. "Every time science has displaced us from the center of things," he says, "it has given back far more in return." It's a truth that this book exemplifies on every luminescent page.
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Mr. Baggini is the author of "The Great Guide: What David Hume Can Teach Us About Being Human and Living Well."" [1]
1. Why We Have A Sense of Self
Baggini, Julian. Wall Street Journal, Eastern edition; New York, N.Y. [New York, N.Y]. 10 Dec 2021: A.15.
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