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The brain, wrote Charles Scott Sherrington, is an “enchanted loom where millions of flashing shuttles weave a dissolving pattern”. The British neuroscientist created this striking image more than 80 years ago, a time when mechanised looms, not computers, embodied the idea of technology. Even so, the symbolism feels relevant. We struggle to talk of our brains or minds without recourse to the machine metaphor: once it was clocks, then looms, and now computers. We say that our brains are hardwired; we talk of our ability to process information.
The quote appears as merely a footnote in Michael Pollan’s new book, A World Appears, a fabulous and mind-expanding exploration of consciousness: how and why we are self-aware. But the whole thing can be read as a lucid and impassioned riposte to Sherrington’s conception of the mind as a machine. In Pollan’s view, we have become imprisoned by such narratives, which have obscured the richness and complexity of human and non-human consciousness. Bridging both science and the humanities, Pollan mines neuroscientific research, philosophy, literature and his own mind, searching for different ways to think about being, and what it feels like.
Pollan’s curiosity was piqued after he took magic mushrooms and began to view the plants around him as sentient. “It seemed obvious that not only were these plants cognisant of their environment, but they also had preferences, agency, and a viewpoint of their own,” he writes. Obvious perhaps for an author on psilocybin, but it turns out there are many scientists who would agree with his conclusion. They call themselves “plant neurobiologists”. The title is deliberately provocative; plants, of course, do not possess neurons, though, as Pollan learns, they exhibit some of the qualities we associate with species that do: plants can learn and form memories, predict changes in their environment and respond appropriately, send and receive signals from other plants, and alter their behaviour depending on circumstances.
Plant neurobiologists hypothesise that the seat of this intelligence is the roots, which form a leaderless network of cells exchanging information through chemical or electrical signals, much like neurons. (Pollan cites the research of Michael Levin, who has shown that simple cells can communicate through bioelectricity, and can even store memories.) This chapter upended many of my assumptions about intelligence and also raised unsettling questions. Can plants make decisions? Do they feel pain? “I cannot help but think of plants as … these locked-in syndrome patients that cannot flag that they are mentally alive,” says one of the researchers.
Pollan himself charts a careful course between anthropomorphism (plants as “locked-in patients”) and its opposite, a wilful denial of their sophistication. He doesn’t think of them as conscious, preferring “sentient”, which he classifies as an evolutionary step before consciousness. A distinguishing feature of consciousness, he argues, is feeling and emotion, which scientists have “located” in the upper brainstem, one of the most ancient parts of the human brain (and one that is also present in other species, something that raises important ethical implications).
Unlike our ability to use language, our emotions have proved resistant to artificial reproduction. Pollan draws us into the weird universe of synthetic consciousness, in which neuroscientists and computer scientists are seeking to build a conscious AI by endowing it with feelings and desires, such as hunger, thirst and the need to rest. These pages are decidedly eerie, but it soon becomes clear that such exercises simply confirm what’s distinctive about human consciousness; as Pollan notes, when an AI registers information, it is not the same as feeling. He refrains from judgment on these experiments, though one of his interlocutors asks a pointed question of the researchers conducting them: “Why don’t they just have a baby?”
I experienced a kind of claustrophobia and estrangement reading about the various theories of consciousness, their soulless lexicon seemingly drawn from a business school manual (one leading hypothesis is called global workspace theory). So too does Pollan, a science writer, yes, but one schooled in the humanities, more concerned with the exploding of categories rather than their strict delineation. Of the 22 or so theories on offer, none, Pollan writes, has come close to resolving the “problem” of consciousness. The metaphors that we have for the mind, largely drawn from the world of machines, are not up to the task (in one of the most interesting passages, he lays out precisely how the human mind is different from a computer; how feelings and thoughts cannot be reduced to the mere processing of information, and are intimately connected to our biology). Those seeking to replicate human-like consciousness on a chip may resemble Sisyphus more than Dr Frankenstein.
Pollan likens the study of consciousness to cosmology: just as we can only examine the universe from within it, there is no way for us to position ourselves outside our own consciousness. You can almost sense his relief when he moves away from the reductionism of neuroscientists to consider the work of those who embrace their own subjective positions. William James appears as a guiding light; the pioneering philosopher and psychologist carefully noted the ambiguities of the human mind, its shifts and nuances. Like James, Pollan experiments on himself, sampling his inner experiences at random times of the day with the assistance of a social psychologist, but he quickly finds that what is going on in his own mind is often beyond the reach of language. The later chapters, which draw on everything from Buddhist thought to modernist literature, remind us of what is obvious if only we stop to notice: that our minds are constantly in flux, remoulding, shifting, flowing.
Much of Pollan’s book reminded me of Siri Hustvedt’s brilliant 2016 extended essay, The Delusions of Certainty, a lucid critique of scientific reductionism. Like that work, Pollan’s book attempts to disentangle the ideas we have inherited about our own minds, an inheritance of which we are not even aware. All too often, these theories have visited “violence” on our own consciousness, he writes. Violence is a strong word, and it implies a harm. So what is the harm, and to whom is it being done? Pollan lives in the Bay Area of California, and, although his book rarely mentions Silicon Valley, it can be read as an act of resistance towards the financial and technological interests that are invested in distancing us from our inner lives and emotions.
He cites the MIT sociologist Sherry Turkle, who wrote: “Technology can make us forget what we know about life.” I’d agree, though I’d add that to forget something, one needs to know it in the first place, and there may come a time when we are so divorced from the richness of our own minds that we will mistake the mere processing of information for consciousness, the machine metaphor for reality. That, perhaps, is the monster that stalks this book: our concern should be less about what kind of AI we might produce – whether a machine may one day experience love or hatred – and more what kind of a human will be fashioned by AI and our interactions with technology; whether we will settle for an impoverished conception of our own minds, or can be reacquainted with its wonders.
