Deep Thoughts: who is I?

Go to work on an ego: How do you transform difficult scientific theories into an evening's entertainment? A leading neuropsychologist explains how he adapted his best-selling book on the brain, soul and 'self' for a theatre audience -- by Paul Broks

I have never bargained with the Prince of Darkness but I do get drawn into wrangles over the soul. They are mostly benign but one woman came to the brink of physical assault. It was during a talk I gave at a literary festival. She told the organisers she just wanted to shake me by the lapels. What had I done to upset her? I'd said that studying brain function and working with brain-damaged people had led me to certain views about the nature of personal identity; that neuroscience had no place for the soul; that the human brain was a storytelling machine, and that the self was a story.

I said that our deepest intuitions about what it means to be a person are based on an illusion. There is no inner essence, no ego, no observing 'I', no ghost in the machine. The story is all and, moreover, the story is enough. It was nothing personal. I've reeled off my litany of self-annihilation ad nauseam since Into the Silent Land was published. Sometimes I feel like shaking myself by the lapels.

The book explores love, loss and personal transformation through neurological case stories and speculative fiction. But if the scientific assault on the soul is one of its themes, so too is the limitation of science. Journeying into the tangled forest of the brain, determined to expose the smoke and mirrors of the illusory self, the narrator hits a block that seems to mark the boundary of scientific explanation. His travels in neuropsychology always lead to a conundrum that science cannot crack: the paradox of consciousness. How does meat become mind? The confused, ambivalent narrator is mostly me.

Mick Gordon, I discovered, is also baffled by his own existence. He read my book and suggested we collaborate on a play - or as he prefers, 'theatre essay'. Formerly Trevor Nunn's associate director at the National Theatre, he is an award-winning director who is not particularly interested in directing plays. For Mick, as for his mentor, the legendary Peter Brook, theatre is a quest for the essence of communication and a medium for the exploration of ideas. The notion of the 'theatre essay' is just this - an examination of explicit themes and questions that makes no compromises in terms of drama or intellectual rigour.

Mick had explored love and death in previous works. Now he had the idea of using Into the Silent Land as the starting point for a dramatic dissection of the self. He travelled down to Plymouth to make his pitch and, over several drinks, he told me there was one question that fascinated him more than any other: is it possible for a person ever to change? My question was this: is it possible ever to remain the same? Thus, in counterpoint, we embarked on the project that became On Ego. Our challenge was to bring the neurology and the philosophy behind these questions to dramatic life. We wanted to move and inspire as well as to inform; we intended to disturb. 'A book should shake us awake like a blow on the skull,' said Franz Kafka. Likewise drama.

Not coincidentally, the deepest mysteries of philosophy are also the universal concerns of drama. In one way or another, all great drama probes the nature of the self and the origins of action. All great drama deals in paradox and conflict. In these terms, neuropsychology offers rich grounds for excavation. These are awesome times. The laser beams of cognitive neuroscience are beginning to penetrate the philosophical fog of centuries. Modern brain scanning procedures have opened windows into the working brain. We see the circuitries of memory and emotion; we see how thought turns to intention, intention to action. We even know the signatures of truth and deceit, written in blood (or rather patterns of blood flow) on the crumpled vellum of the cortical mantle.

But peering into the intricate machineries of the brain one is bound to inquire - who's running the show? The answer is: no one. Neuroscience tells us that the functions of the brain have a life and logic of their own. Your conscious awareness of choosing to perform an action lags behind the neural processes that determined the choice by roughly half a second. So where exactly do 'you' figure? Are you really the reflective, autonomous being you believe yourself to be or, rather, a shadow-puppet shaped by the firings of a hundred billion brain cells?

We settled on two central questions: what (if any) are our essential properties as persons? And what changes can we survive? They are developed through two intertwining stories, one a science fiction fantasy (which deals primarily with the first question), the other a sequence of snapshots from the life of a woman with a progressive brain disorder (which deals mainly with the second). Alex, a neuroscientist, finds himself accidentally duplicated when a teleportation exercise goes wrong. While the replicated Alex gets on with his life oblivious to the plight of his twin, the original is confined in a cell and put under heavy persuasion to end his life. But which version of Alex has the right to live? And if suicide is a recommended course of action, wouldn't murder, in the circumstances, also be justified? To be two or not to be, that is the question. As we tease out the philosophical strands of the teleportation adventure we are also drawn into the story of Alex's wife, Alice, who has a brain tumour. We visit the interior of her transforming mind. As the disease progresses she comes to disown her husband. Each was the other's mirror. We define ourselves by those we love. What is he, what can he become, without her?

The juxtaposition of science fiction and personal tragedy was dramatically risky, we knew. I'd played similar tricks in my book but what thrives on the page does not necessarily survive the constraints of the stage. We had begun work on the piece with a series of workshops at the National Theatre Studio, the first of which was marked by an exquisite coincidence. Arriving at Paddington, I glimpsed a gaunt but handsome-looking man emerging from the Underground station. A second glance confirmed that it was Jeffrey Gray, the distinguished professor of psychology I'd first encountered at Oxford in the late Seventies. He disappeared and I continued on my way to Waterloo and the Studio where, over coffee, I found myself chatting to an actress called Leila. She told me that her father was a psychologist and that he was writing a book about consciousness. Perhaps I knew him: Jeffrey Gray. I was flattered that Jeffrey subsequently reviewed Into the Silent Land and regret that I never had the opportunity to tell him how much I admired the book that he'd been working on - Consciousness: Creeping Up on the Hard Problem. Its publication coincided with Jeffrey's death. I'd been reading it the day I heard the news. I felt a jolt, but the author's death does not affect the life of the book. Bizarrely, it's the opposite. Something of the person reasserts itself in the text. This tells us something about what it is to be a person (there are mortal and immortal elements) and about the turns of magical thinking that seem to be involved in perceiving others and ourselves. It's but one small step to a belief in souls.

Didn't I find it depressing, someone once asked, to see myself as a vacant, soulless machine? No, I find it inspirational - at least I do when I stop to think about the unfathomably intricate device that packs my skull and the chasm that separates our knowledge of its workings from the universe of experience it generates. Being a machine does not stop me getting on with the things that matter. I accept that one day the device will stop, and so shall I. While I am not thrilled at the prospect of my bodily apparatus grinding to an oblivious halt, it is not something that fills me with dread either, or even sparks the slightest flicker of apprehension. Some people find this offensive. But if you don't believe you have a soul, you don't fear losing it. As John Updike wrote, 'We are immortal for as long as we live'.

Views of the self:

Ego theory
The intuitive, common sense view. There is an 'I', an experiencer of experiences that constitutes the essential core of every person. Descartes believed that our capacity for self-awareness is due to the possession of an immaterial soul.

Bundle theory
Origins in Buddhist teaching with modern formulations by David Hume and Derek Parfit. Rejects the idea that actions and experiences are owned by some inner essence, ego, or 'I'. A life is a long series - or bundle - of interconnected mental states and events.

Biological self
The self as body. Daniel Dennett refers to: 'The fundamental biological principle of distinguishing self from world, inside from outside ... to distinguish self from other, in order to protect oneself.'

Extended self
A unified, continuous being journeying from a remembered past to an anticipated future, with a repertoire of skills, stores of knowledge and dispositions to act in certain ways. The extended self is shaped by neural systems distributed throughout the brain, especially those involved in language and long-term memory.

Minimal self
The self of the present moment. In the words of Antonio Damasio, this core self is 'a transient entity, recreated for each and every object with which the brain interacts'. It arises from brain systems involved in regulating body states and mapping body signals.

(Paul Broks is a clinical neuropsychologist who teaches at the University of Plymouth. On Ego is at the Soho Theatre, London W1 until 7 January. Tickets: 0870 429 6883. Into the Silent Land: Travels in Neuropsychology.)