Michael Pollan's 4-Year Quest to Uncover Consciousness

Psychology, it's said, has a long past but a short history. A popular version lists three stages.

First, around the turn of the 20th century, psychologists tried to capture the stream of conscious experience in the net of introspection. The behaviourists then declared the mind off limits, arguing that psychology should study observable behaviour rather than subjective experience. Finally, the emergence of computers spurred the cognitive revolution of the 1960s, which brought the mind back in from the cold, in a new science of information processing.

This narrative arc is appealing, but substantially wrong. Introspection was never a dominant method in psychology. Psychologists continued to study mental processes throughout the behaviourist dark age. And some argue the story leaves out a crucial fourth stage. Cognitive psychology may have made great strides in understanding the mind as computation - neuroscientists helping to figure out the brain's hardware - but it failed to grasp something vital.

Review: A World Appears: A Journey Into Consciousness - Michael Pollan (Allen Lane)

Enter the study of consciousness - the subject of a new book by accomplished journalist and academic Michael Pollan. For the past few decades, philosophers, psychologists and neuroscientists have tried to redeem this once-taboo concept and uncover its secrets. That effort has been driven by the belief that mainstream cognitive science cannot solve the so-called " hard problem " of how and why subjective experience arises.

The study of consciousness has been enormously successful in attracting intellectual talent and public attention. Many specialist academic journals have been founded and blockbusters written . Distinguished scientists from other fields - Nobel Prize-winning biologist Francis Crick and physicist Roger Penrose among them - have beaten a path to this new scholarly El Dorado.

All this cerebral effort has been less than enormously successful. No consensus view has formed on the nature or underpinnings of consciousness, on what kinds of entity possess it, or even on how the field's key questions and concepts should be defined. New theories of consciousness sprout faster than they can be weeded out by evidence - and philosophers continue to hold radically different views on its metaphysics.

Pollan's book, A World Appears , wades into this morass in search of clarity. He is the author of numerous books on the intersection of nature and culture, with special emphasis on food , plants and psychedelics . This book is the product of an extended quest to understand consciousness - he wonders if it might be "a socially (and scientifically) acceptable proxy for the search for the soul".

It is a splendidly intelligent, humane and curious exploration of some truly confounding ideas.

The basement of consciousness

Pollan divides his book into chapters on sentience, feeling, thinking and the self. These labels struggle to contain the many overlaps and blurred boundaries between these concepts: consciousness studies is a minefield of contested definitions.

The "sentience" chapter begins by attempting to "furnish the basement of consciousness". Here, Pollan presents some astonishing work by researchers who cheekily describe themselves as "plant neurobiologists", knowing that plants lack nervous systems.

Some plants show evidence of goal-direction, recognition of genetic relatedness, and responses akin to pain, sleep and anaesthesia. When damaged or stressed, some produce ethylene, an anaesthetic that inhibits their movement in response to touch. Root-tips can navigate mazes in search of nutrients, like subterranean lab rats seeking cheese.

Greenery that first appears static and inert looks very different when we imagine a being with its head in the ground, operating on a different timescale, he writes. In slow motion, a vine's growing tendril seems to manifest a sense of purpose.

What might the ethical implications of plant sentience be? Would we be obliged, as the botany professor in Samuel Butler's 1872 satire Erewhon argues, only to eat plants that "had died a natural death, such as fruit that was lying on the ground and about to rot, or cabbage-leaves that had turned yellow in late autumn". Must we "plant the pips of any apples or pears […] or […] come near to incurring the guilt of infanticide"?

Perhaps the implications are less extreme than Butler suggests, but the findings Pollan lays out might make us less anthropocentric - and zoocentric - in our moral concern.

Pollan's discussion of "feeling" explores the ways consciousness is grounded in the body and tied to emotion. Challenging views that locate it in the brain's more recently evolved cortical regions, Pollan speaks to researchers who ground it in the more "primitive" brain stem. Subjective feeling may be the body's way of making the mind keep it alive, he writes, alerting us to departures from a desired internal state and enabling us to problem-solve our way forward.

If consciousness is embodied and affective, building a conscious machine might seem a fool's errand. Pollan talks to scientists who aspire to do just that - and believe success is imminent. Pollan's scepticism is undisguised. He questions the equation of consciousness with software and doubts that feeling, unlike thinking, can be simulated.

"The consciousness [AI enthusiasts] are hoping to install in computers depend on feelings that will be weightless absent the vulnerabilities of our mortal flesh."

Mysteries of the mind

Pollan's discussion of "thinking" explores the contents of consciousness. His doubts are again on display. Can we really "step outside the stream of consciousness in order to observe it from its banks"? And can the stream be separated into distinct elements and quantified?

Pollan compares the attempts of a psychologist to sample inner experience with those of phenomenologists - philosophers who hope to understand the structure of the subjectivity - and writers of modernist fiction. He concludes that this most basic of questions - what is on our minds? - remains a mystery.

In a final chapter, Pollan investigates our sense of self: "the crown of consciousness" to some and a seductive illusion to others, notably David Hume and the Buddha .

The self remains elusive: "to look for the subject is to treat it as an object, which is to negate it." Pollan considers ways of escaping the self through psychedelics, hypnosis and meditation, before entertaining the possibility of pure awareness in the absence of an experiencing self.

Scientists or sages?

Pollan is an astute and amiable guide through this strange territory. He talks with many of the leading figures in the study of consciousness.

They include Australian philosopher David Chalmers , Portugese-American neuroscientist Antonio Damasio (who argues emotions are a crucial component of decision-making), and American developmental psychologist Alison Gopnik , as well as many lesser-known ones.

He engages deeply with their ideas and spares his interlocutors no hard questions. He makes it clear to them (and his reader) when he is unpersuaded, as when one psychologist informs him his inner life seems a little empty. He is knowledgeable about the science of consciousness, but also determined to give the humanities their due.

If anything, Pollan aligns himself more with the poets, Romantics and sages - and their psychedelic fellow travellers - than with the scientists and academic philosophers. One grasps the subtle truth of subjective experience, while the other is often reductive and obscure.

The book closes with a stay in a Zen retreat in search of "unthinking presence", which reinforces the message that seeking first-person encounters with experience is more illuminating than engaging in third-person academic studies of it.

Pollan's reservations about the academic study of consciousness are perhaps a little unfair. Is the fact that neuroscientists have proposed 22 accounts of consciousness really "a pretty good indication that the field is flailing"? Should we wring our hands and rend our garments because philosophers hold radically incompatible accounts of consciousness: an emergent property of brains, an illusion, or a fundamental attribute of the universe, like gravity?

Perhaps the question of consciousness doesn't have a single answer. As Francis Crick found when he leapt confidently into the field of consciousness studies after co-discovering the genetic basis of life, some big, juicy questions are less scientifically tractable than others.

Consciousness studies may be expanding in a hundred directions rather than converging on a singular truth - and that may be a good thing.

The dream of a final theory

The fruitfulness of consciousness studies could be a valuable preparation for a later process of Darwinian selection. Just as neural connections proliferate in the developing brain and are then pruned back to enhance cognitive efficiency, exploring the broad field of conceptual possibilities before homing in on an integrating theory may optimise the pursuit of knowledge.

Consciousness may be like the proverbial elephant with the blind men. Alternative theories palpate different parts of the beast, perhaps enabling a better understanding of the whole to emerge.

Alternatively, there may be no elephant. Like morality or mental illness, consciousness may be an umbrella concept that refers to a multitude of different phenomena. If this is the case, we should be thankful for the findings of consciousness researchers.

These may never cohere into a unifying account of their target, but they shed new light on many other things along the way - from plant sentience to human perception, and from inner speech to artificial intelligence.

Pollan warns his readers that his book is likely to make them more confused and less sure of what they know. That's how he felt when he finished writing it. A World Appears is a delightful read for anyone who enjoys being intelligently befuddled by a master of the craft.

Nick Haslam receives funding from the Australian Research Council.