Science & Technology

The Hard Problem Gets Harder

After decades of neuroscience, the mystery of consciousness is not shrinking. It is expanding — into plants, into bodies, into the cosmos itself

chuppala nagesh bhushan|  15th June 2025

THERE is a peculiar irony at the heart of consciousness research. The thing being studied — the felt quality of inner experience — is the only phenomenon in the universe of which every human being has direct, first-person knowledge. And yet, after thirty years of concerted scientific effort, the mystery of consciousness has not diminished. It has deepened.

This is the central tension of "A World Appears: A Journey Into Consciousness", a new book by the science writer Michael Pollan, better known for his investigations into food and, more recently, psychedelics. The book is an ambitious tour through the latest theories of mind — from neural workspace models to panpsychism — and Mr Pollan arrives at its end, if anything, more bewildered than when he began. That bewilderment, he argues, is the appropriate response.

"The closer we look at consciousness," he writes, "the weirder it gets. The more we try to describe it, the more our language begins to fail." He finds this not cause for despair but for delight — a reminder that a central question about the universe is one that unfolds, perpetually, inside each of us.

Gossamer wisps of mentation

Mr Pollan opens with a deceptively simple experiment. He spent several days wearing a beeper, courtesy of Russell Hurlburt, a psychologist at the University of Nevada, Las Vegas who has spent fifty years sampling people's inner experience at random moments. When the beeper sounded, Mr Pollan was required to record exactly what had been passing through his mind at that precise instant. The results were humbling.

His thoughts, it turned out, were neither literary nor profound. Standing in a bakery queue, he was weighing whether to buy a bread roll or use a heel of loaf already at home. The mental image involved, he discovered on reflection, was less an actual roll than something resembling an emoji of one. When Professor Hurlburt pressed him to characterise whether his inner voice had spoken the thought or whether he had somehow heard it, Mr Pollan found he had no answer.

The episode points to something that William James, the nineteenth-century father of American psychology, identified long before modern neuroscience existed: that mental life is vastly more intricate, shadowy and transient than ordinary introspection suggests. James described its textures with extraordinary precision — the "fringe of unarticulated affinities" that surrounds each thought, the way one idea colours the next before it has fully formed, the stream-like quality that makes it impossible to extract any single thought without disturbing the whole. Contemporary scientists, in Mr Pollan's view, have not improved on him. Their reductions — to qualia, to neural correlates, to workspace broadcasts — tend to flatten precisely what James illuminated.

"The fact that something so close can remain so mysterious — that a central question about the universe is happening inside of us all of the time — I find that so delightful." — Michael Pollan, A World Appears

 

Can you anaesthetise a plant?

One of the book's most unsettling chapters concerns plant consciousness — or, more cautiously, plant sentience. A group of researchers who call themselves plant neurobiologists (the name is deliberately provocative: plants have no neurons) have shown that mimosa pudica and carnivorous plants can be rendered apparently insensible using anaesthetic agents including xenon gas, an inert substance that should, by conventional chemistry, have no pharmacological effect whatsoever. Expose the plants to it, and they stop responding. Remove it, and they recover.

Stefano Mancuso, the Italian botanist who leads much of this work, has also shown that plants exhibit sleep-like states meeting criteria proposed by Giulio Tononi — criteria previously thought to apply only to higher animals. The philosopher Thomas Nagel famously proposed that a creature is conscious if "it is like something" to be that creature. Mr Mancuso's plants, in their waking and sleeping states, at least raise the question.

Mr Pollan is careful not to overreach. A thermostat responds to stimuli without it being "like anything" to be a thermostat, and plants may be no different. But the experiments, he argues, at least return us to something resembling animism — the intuition, found across traditional cultures and in most children before formal schooling extinguishes it, that the living world is saturated with experience. Western scientific materialism is, in this view, a localised and possibly temporary consensus rather than an eternal truth.

The body writes first

A second major theme of the book is the primacy of the body in conscious experience — a theme that cuts against the prevailing tendency to seat consciousness firmly in the cortex. The brain, Mr Pollan reminds the reader, exists to keep the body alive, not the other way around. Feelings — hunger, itchiness, the dull dread of social threat — originate in the body and are subsequently interpreted by the brain, not generated there from scratch.

This insight, associated most powerfully with the neuroscientist Antonio Damasio, has peculiar implications for arguments about artificial consciousness. If feelings are not simply information signals but irreducibly somatic events — if moral disgust is literally processed through the gut, as one experiment showed by demonstrating that ginger, which calms the stomach, measurably reduced subjects' responses to morally offensive imagery — then it is very hard to see how a system without a vulnerable, mortal body could replicate them. A feeling, Mr Pollan suggests, has no weight if it carries no risk.

The neuroscientist Mark Solms has proposed that consciousness is essentially "felt uncertainty" — the space that opens when automated responses are insufficient and genuine decision-making is required. It is a compelling theory. But Mr Pollan notes its limits: psychedelic or meditative consciousness, which is characterised by an almost overwhelming richness of raw experience rather than by anxious deliberation, seems to describe something different — something closer to what the developmental psychologist Alison Gopnik calls "lantern consciousness", the diffuse, 360-degree attentiveness of a young child before schooling narrows it to the spotlight of adult cognition.

Idealism at the frontier

The book's most philosophically adventurous chapters follow scientists who have, apparently, been changed by their own minds. Christof Koch — a neuroscientist who ran the Allen Brain Institute and spent his career hunting for the neural correlates of consciousness — travelled to Brazil and underwent a series of ayahuasca sessions. He returned, to his own evident astonishment, entertaining philosophical idealism: the proposition that consciousness is not an emergent property of matter but the fundamental substrate from which matter arises.

This is not a fringe position. Panpsychism — the view that some form of experience is a basic feature of reality, as fundamental as mass or charge — is taken seriously by a growing number of philosophers. Its appeal lies partly in the apparent failure of its alternatives: standard materialist accounts of consciousness tend, when pressed, to dissolve into what Mr Pollan calls "abracadabra" — the word "emergent" used as a magic formula to skip over precisely the step that needs explaining.

Mr Koch used the analogy of a colour scientist who has spent her life in a black-and-white room. She knows everything there is to know about wavelengths and retinal cones. The day she steps into a coloured world, something new has been added to her knowledge that no amount of prior science could have given her. A psychedelic experience, he argues, is structurally similar: it is not reducible to the chemistry that induced it.

The sovereignty of attention

The book's final chapters turn from theory to politics — of a kind. Mr Pollan argues that consciousness is not merely a scientific puzzle but a moral and civic resource, and one currently under siege. Modern capitalism, he contends, has an interest in colonising inner life: attention captured is attention monetised. Reed Hastings, the co-founder of Netflix, once described sleep as his company's primary competitor. Social media algorithms are not merely distracting; they are, in a meaningful sense, determining what a very large number of people think about, and when, and in what emotional register.

The neuroscience supports his concern. Narrow, screen-focused attention corresponds to a physiologically different state — tight pupil, constricted peripheral vision, elevated cortisol — from the broad, associative gaze that characterises creative thought, contemplation, or walking in nature. A culture that persistently promotes the former and erodes the latter is not merely less pleasant to live in; it is, Mr Pollan suggests, more susceptible to manipulation and less capable of genuine democratic deliberation.

The remedies he proposes are not novel — meditation, time in nature, mind-wandering, protecting stretches of the day from digital intrusion — but the argument for them is more rigorous than self-help conventions usually allow. Kalina Christoff, a psychologist who studies spontaneous thought, has shown that highly creative individuals — composers, novelists, mathematicians — typically work only four or five hours a day and spend the rest in apparently unstructured wandering. The breakthroughs tend to arrive during the wandering.

Mr Pollan ends his book in a cave in New Mexico, at the Upaya Zen Centre, where the teacher Joan Halifax declines, with some elegance, to give him the interview he has travelled to obtain. She has, she tells him, "divested herself of meaning". Left alone with himself for several days — no electricity, no media, no interlocutors treating him as a self and thereby reinforcing the illusion of one — he finds the borders of his identity becoming porous. He wakes one night, walks outside and looks up at a moonless sky. The stars, he writes, seem not to be out there but to extend all the way down to where he stands, as if the two of them — man and cosmos — share the same intergalactic blanket.

What he took from the experience was a shift in framing: from consciousness as a problem to be solved to consciousness as a fact to be inhabited. The hard problem, he decided, may not have a solution. It may be, instead, the permanent condition — the irreducible strangeness of there being something rather than nothing at all, an inside to this universe, a view from somewhere. The appropriate response, he concluded, is not frustration but wonder.

 

A World Appears: A Journey Into Consciousness. By Michael Pollan. Allen Lane; 400 pages.