The Mystery of Consciousness

By Oliver Burkeman, originally published at The Guardian.

The brain, [David] Chalmers began by pointing out, poses all sorts of problems to keep scientists busy. How do we learn, store memories, or perceive things? How do you know to jerk your hand away from scalding water, or hear your name spoken across the room at a noisy party? But these were all “easy problems”, in the scheme of things: given enough time and money, experts would figure them out. There was only one truly hard problem of consciousness, Chalmers said. It was a puzzle so bewildering that, in the months after his talk, people started dignifying it with capital letters – the Hard Problem of Consciousness – and it’s this: why on earth should all those complicated brain processes feel like anything from the inside? Why aren’t we just brilliant robots, capable of retaining information, of responding to noises and smells and hot saucepans, but dark inside, lacking an inner life? And how does the brain manage it? How could the 1.4kg lump of moist, pinkish-beige tissue inside your skull give rise to something as mysterious as the experience of being that pinkish-beige lump, and the body to which it is attached?

[W]e know an astonishing amount about the brain: you can’t follow the news for a week without encountering at least one more tale about scientists discovering the brain region associated with gambling, or laziness, or love at first sight, or regret – and that’s only the research that makes the headlines. Meanwhile, the field of artificial intelligence – which focuses on recreating the abilities of the human brain, rather than on what it feels like to be one – has advanced stupendously. But like an obnoxious relative who invites himself to stay for a week and then won’t leave, the Hard Problem remains. When I stubbed my toe on the leg of the dining table this morning, as any student of the brain could tell you, nerve fibres called “C-fibres” shot a message to my spinal cord, sending neurotransmitters to the part of my brain called the thalamus, which activated (among other things) my limbic system. Fine. But how come all that was accompanied by an agonising flash of pain? And what is pain, anyway?

Questions like these, which straddle the border between science and philosophy, make some experts openly angry. They have caused others to argue that conscious sensations, such as pain, don’t really exist, no matter what I felt as I hopped in anguish around the kitchen; or, alternatively, that plants and trees must also be conscious. The Hard Problem has prompted arguments in serious journals about what is going on in the mind of a zombie, or – to quote the title of a famous 1974 paper by the philosopher Thomas Nagel – the question “What is it like to be a bat?” Some argue that the problem marks the boundary not just of what we currently know, but of what science could ever explain. On the other hand, in recent years, a handful of neuroscientists have come to believe that it may finally be about to be solved – but only if we are willing to accept the profoundly unsettling conclusion that computers or the internet might soon become conscious, too.

Not everybody agrees there is a Hard Problem to begin with – making the whole debate kickstarted by Chalmers an exercise in pointlessness. Daniel Dennett, the high-profile atheist and professor at Tufts University outside Boston, argues that consciousness, as we think of it, is an illusion: there just isn’t anything in addition to the spongy stuff of the brain, and that spongy stuff doesn’t actually give rise to something called consciousness. Common sense may tell us there’s a subjective world of inner experience – but then common sense told us that the sun orbits the Earth, and that the world was flat. Consciousness, according to Dennett’s theory, is like a conjuring trick: the normal functioning of the brain just makes it look as if there is something non-physical going on. To look for a real, substantive thing called consciousness, Dennett argues, is as silly as insisting that characters in novels, such as Sherlock Holmes or Harry Potter, must be made up of a peculiar substance named “fictoplasm”; the idea is absurd and unnecessary, since the characters do not exist to begin with. This is the point at which the debate tends to collapse into incredulous laughter and head-shaking: neither camp can quite believe what the other is saying. To Dennett’s opponents, he is simply denying the existence of something everyone knows for certain: their inner experience of sights, smells, emotions and the rest. (Chalmers has speculated, largely in jest, that Dennett himself might be a zombie.) It’s like asserting that cancer doesn’t exist, then claiming you’ve cured cancer; more than one critic of Dennett’s most famous book, Consciousness Explained, has joked that its title ought to be Consciousness Explained Away. Dennett’s reply is characteristically breezy: explaining things away, he insists, is exactly what scientists do. When physicists first concluded that the only difference between gold and silver was the number of subatomic particles in their atoms, he writes, people could have felt cheated, complaining that their special “goldness” and “silveriness” had been explained away. But everybody now accepts that goldness and silveriness are really just differences in atoms. However hard it feels to accept, we should concede that consciousness is just the physical brain, doing what brains do.

Solutions have regularly been floated: the literature is awash in references to “global workspace theory”, “ego tunnels”, “microtubules”, and speculation that quantum theory may provide a way forward. But the intractability of the arguments has caused some thinkers, such as Colin McGinn, to raise an intriguing if ultimately defeatist possibility: what if we’re just constitutionally incapable of ever solving the Hard Problem? After all, our brains evolved to help us solve down-to-earth problems of survival and reproduction; there is no particular reason to assume they should be capable of cracking every big philosophical puzzle we happen to throw at them. This stance has become known as “mysterianism” – after the 1960s Michigan rock’n’roll band ? and the Mysterians, who themselves borrowed the name from a work of Japanese sci-fi – but the essence of it is that there’s actually no mystery to why consciousness hasn’t been explained: it’s that humans aren’t up to the job. If we struggle to understand what it could possibly mean for the mind to be physical, maybe that’s because we are, to quote the American philosopher Josh Weisberg, in the position of “squirrels trying to understand quantum mechanics”. In other words: “It’s just not going to happen.”

Or maybe it is: in the last few years, several scientists and philosophers, Chalmers and Koch among them, have begun to look seriously again at a viewpoint so bizarre that it has been neglected for more than a century, except among followers of eastern spiritual traditions, or in the kookier corners of the new age. This is “panpsychism”, the dizzying notion that everything in the universe might be conscious, or at least potentially conscious, or conscious when put into certain configurations. Koch concedes that this sounds ridiculous: when he mentions panpsychism, he has written, “I often encounter blank stares of incomprehension.” But when it comes to grappling with the Hard Problem, crazy-sounding theories are an occupational hazard. Besides, panpsychism might help unravel an enigma that has attached to the study of consciousness from the start: if humans have it, and apes have it, and dogs and pigs probably have it, and maybe birds, too – well, where does it stop?

This article was originally written for and published at The Guardian, and is partially reproduced here without the permission of the author, who is not affiliated with this website or its views.