“Once your brain is vaporised, the lights go out for good. Even an exact physical duplicate of your body and brain would not be you—although it would certainly believe it was.”

Self

by Barry Dainton (Penguin, £8.99)

Me, Myself and Why: Searching for the Science of the Self

by Jennifer Ouellette (Penguin US, £9.99)

Most of us, when we look in the mirror, have a sense that behind the eyes looking back at us is a me-ish thing: a self. But this, we are increasingly told, is an illusion. Why? Well, according to neuroscientists, there is no single place in the brain that generates a self. According to psychologists, there is no little commander-in-chief in our heads directing our behaviour. According to philosophers, there is no “Cartesian ego” unifying our consciousness, no unchanging core of identity that makes us the same person from day to day; there is only an ever-shifting bundle of thoughts, feelings and memories.

In the last few years, a number of popularising books, bearing titles like The Self Illusion and The Ego Trick, have set out the neuroscientific/psychological/philosophical case against the self. Much has been made of clinical cases where the self seems to malfunction spectacularly: like Cotard syndrome, whose victims believe they do not exist, even though they admit to having a life history; or “dissociative identity disorder,” where a single body seems to harbour multiple selves, each with its own name, memory, and voice. Most of us are not afflicted by such exotic disorders. When we are told that both science and philosophy have revealed the self to be more fragile and fragmentary than we thought, we take the news in our stride and go on with our lives.

But perhaps we should be paying closer attention. For example, there is striking evidence (detailed by the Nobel laureate Daniel Kahneman in his book Thinking, Fast and Slow) that each of us has a “remembering self,” which makes decisions, and an “experiencing self,” which actually does the living. And when the remembering self looks back on an experience and decides how enjoyable it was, it can arrive at an assessment that is quite out of whack from what the experiencing self actually endured. It is your remembering self that tyrannically resolves to take another family vacation this summer, even though your voiceless experiencing self was miserable for most of the last one. Evidently, the subtleties of the self are of practical as well as scholarly interest.

Barry Dainton’s Self and Jennifer Ouellette’s Me, Myself and Why stand out, in different ways, from the recent crop of books that seek to undermine our sense of self-identity. Dainton, a philosopher who teaches at the University of Liverpool, is a dissenter from the no-self consensus. He can tell you exactly what your self really is and how to keep track of it over time, even if it somehow escapes your body (which he appears to think is possible). Dainton presents a theory of the “core self,” in all its philosophical purity. In contrast, Ouellette is concerned with the “extended self,” the sum total of all we turn out to be: genetically, socially, temperamentally, sexually. An American science journalist, she wants us to understand how genes and environment conspire to make each of us idiosyncratically singular—indeed, more singular than you might have imagined (as in the case of a transgender person mentioned by Ouellette who refers to her genitalia as “Schrödinger’s vagina”). Ouellette goes to heroic lengths to explore her own self, on one occasion even dropping LSD in an attempt to dismantle it temporarily.

The basic question about the self is: what, in essence, am I? Is my identity rooted in something physical (my body/brain) or something psychological (my memories/personality)? Normally, physical and mental go together, so we are not compelled to think of ourselves as primarily one or the other. But thought experiments can vex our intuitions about personal identity. In An Essay Concerning Human Understanding (1689), John Locke imagined a prince and a cobbler miraculously having their memories switched while they sleep: the prince is shocked to find himself waking up in the body of the cobbler, and the cobbler in the body of the prince. To Locke, it seemed clear the prince and the cobbler had in effect undergone a body swap, so psychological criteria must be paramount in personal identity.

A more contemporary thought experiment along these lines involves “teleportation.” Suppose you want to get to Mars in a hurry. Instead of going in a spaceship, you opt to be beamed there. You enter a teleportation chamber on Earth, where a complete scan of your body is done, after which your body is vaporised; then the information is sent at the speed of light to Mars, where a 3D printer creates a perfect duplicate of your body, right down to the cut on your upper lip you got from shaving that morning. You walk out of the receiving cubicle on Mars after just a few minutes of unconsciousness.

Or do you? Is teleportation really a mode of travel? Might it not rather be a mode of death? It maintains perfect psychological continuity while destroying your original body and brain.

For Derek Parfit, who presented this thought experiment in his 1984 book, Reasons and Persons, this type of teleportation is a survivable process. Psychological continuity, Parfit argued, preserves what matters in personal identity. But not all philosophers agree with this neo-Lockean view. Thomas Nagel, for one, thinks that the correct criterion for personal identity is physical, not psychological. The key to your identity, Nagel has suggested, is the physical object that is causally responsible for the continuing existence of your consciousness: your brain. On this “I am essentially my brain” view, you cannot survive teleportation of the kind Parfit describes. Once your brain is vaporised, the lights go out for good. Even an exact physical duplicate of your body and brain would not be you—although it would certainly believe it was.

So which will it be, the psychological criterion or the physical? Those would seem to be the only options on the table (unless you’re one of those benighted people who believe in immaterial souls). But in Self, Dainton stakes out what he takes to be a novel position—and a “very radical” one, by his own estimation. What is critical to your identity, Dainton claims, has nothing to do with your psychological make-up. It is your stream of consciousness that matters, regardless of its contents. That’s what makes you you. As long as “your consciousness flows on without interruption, you will go on existing”—even if you have massive amnesia, or some evil scientist replaces your psychology with a duplicate of Steve Coogan’s.

But what if you undergo anaesthesia, or get knocked out, or simply doze off? Dainton is aware that such interruptions in the stream of consciousness pose a problem for his initial conception, so he adjusts it a bit. Your self is not your stream of consciousness, which admittedly stops and starts; rather, it is your “capacity” for consciousness, which is still there even when it is inactive during dreamless sleep. “According to my account of the self,” Dainton writes, “there is a very real sense in which we are nothing but potential.” The self, to use his term, is a “C-capacity”—the “C” standing for “consciousness.”

This seems to be an awfully austere view of the self. Am I really just a naked potential for consciousness, stripped of all psychological “quiddity,” inherent nature? If so, what makes my self different from yours? Well, our C-capacities are embodied in different brains. But if C-capacities get their identities from the brains that realise them, then Dainton’s theory is not so novel after all. It is merely Nagel’s “I am my brain” position, disguised by some ungainly new terminology. But Dainton suggests that, given the right circumstances, a single stream of consciousness might be able to flow from one brain to another—or even from a brain into a computer. All that is required is the right kind of “bridge” (or perhaps we should say “plumbing,” to avoid mixing our metaphors).

In fairness to Dainton, interesting philosophical propositions often sound like caricatures when they are ripped out of the context of careful reasoning in which they naturally live. And Dainton’s reasoning is not just careful, but often clever. It is also fun to follow, thanks to his relaxed and humorous prose. In a brief volume he ranges over a vast conceptual territory, lucidly presenting current views of how consciousness fits into the physical world, and speculating with brio on the fate of the self in a future age of brain-augmentation and virtual reality.

I only wish Dainton’s own conception of the self was not so minimal. As he himself acknowledges, it leaves untouched the issues about the self raised by contemporary neuroscience and psychology. It says nothing about the role of the conscious self as the (real or deluded) originator of our choices and actions. And, unlike Derek Parfit’s view of the self, it seems to have no implications for our attitude toward death. If I am in essence nothing but a capacity for consciousness, how should I feel about the inevitable extinction of this bare capacity, as opposed to what Philip Larkin called the “lading-list” of contingencies with which it becomes freighted over the course of my life?

Philosophy alone cannot give us an idea of how weird and extensive that “lading-list” of the self is. For that, we need science, in all its laboratory-bench messiness. And it is hard to imagine a more delightful guide to the science of self than Ouellette. In Me, Myself, and Why, she uses all the devices of contemporary genetics, brain scanning and personality testing to delve deep into the formation of her own self.

The book opens with the author, who was adopted as a child and never knew her biological mother, getting a first look as an adult at her faded onion-skin birth certificate, and marvelling at the unfamiliar name that it bears: “fragments of a self that might have been.” She sends a bit of her saliva in the mail to a genetic-testing company called 23andMe to get an idea of the DNA she inherited. This becomes the pretext for an informative account of how genes can fine-tune our personalities. (People with a long version of a gene that codes for dopamine-receptor molecules, for example, “tend to score higher on extroversion and novelty-seeking. The longer the gene, the greater the need for novelty.”) Ouellette explains why people are “surprisingly good” when it comes to assessing their inner feelings and insecurities, but are much poorer at assessing their outward traits, like intelligence and attractiveness. Discussing narcissicism, she notes that celebrities test higher than average for this trait, with female reality TV stars scoring off the chart.

The most entertaining chapter in this very entertaining book concerns the author’s acid trip—undertaken in a spirit of pure enquiry and ending in psychedelic bathos. She describes the history of LSD and psilocybin, what little is understood about their temporary fragmenting effect on the brain, and their positive potential for curing cluster headaches, breaking the hold of alcoholism, and generally “rebooting” a brain that is caught up in destructive loops. What LSD is no good for is “mind control,” as the CIA, to its disappointment, discovered during the Cold War when it set up a string of brothels in San Francisco where prostitutes would slip their johns a tab of acid so agents could observe its effects through two-way mirrors.

Ouellette treads lightly over philosophical ground, but she does take up the deep question of how different parts of the brain might collude to generate self-consciousness. A robust sense of self seems to arise in us by the age of two, when children learn to recognise themselves in the mirror. Chimpanzees can also do this, and are thus believed to be endowed—afflicted?—with selfconsciousness; but few if any other species pass the mirror test. Yet even the humble roundworm C elegans, with its paltry 302 neurons and 2,462 synaptic connections (which scientists have exhaustively mapped), has a single neuron devoted to distinguishing its body from the rest of the world. “I think it’s fair to say that C elegans has a very primitive self-representation” comments the philosopher-neuroscientist Patricia Churchland—indeed, she adds, “a self.”

If the spectrum of selfhood begins with the roundworm, surely it ends with Proust—whose own oversubtle explorations of memory and the self are sadly neglected in these two otherwise estimable books. Moving from Barry Dainton’s philosophical conception of the self—pure, pristine potential—to the endlessly variegated empirical self traced by Jennifer Ouellette, I was reminded of Proust’s description (near the beginning of The Guermantes Way) of what it’s like to wake up out of a leaden slumber. At first, there’s just a glimmer of undefined consciousness; you’re not even a person. Then gradually, in a sort of resurrection, you recover your thoughts, your memories, your personality; you become you again. Proust’s narrator likens the awakening process to finding a lost object. What baffles him is how, “among the millions of human beings one might be,” he unerringly manages to lay his hands on the very self he was the day before. Puzzling as the self is, that might be one puzzle too many.