The problem of personal identity - of what makes you, you - has for a long time been investigated through thought experiments. John Locke asked us to imagine what it would mean to say that your immortal soul had in a past life been that of a warrior who fell at, say, the seige of Troy - given that you have no actual memories of being that warrior, and only the most coincidental resemblances in personality, outlook, knowledge, and beliefs. Leibniz asked us if we'd agree to 'become' the Emperor of China, on the sole condition that we took with us no memories of our present actual life. In this way, they tried to bring into focus our intuition that what matters in personal identity is continuity of memory and personality, and that our belief or lack of it in any immortal spark is strictly irrelevant.
But the self itself may not even be a mortal spark.
At a session chaired by Steven Gale, Julian Baggini spoke yesterday (Monday 22 August) on his book The Ego Trick, in which he explains the 'bundle theory' of personal identity, long familiar in the teachings of Buddhism in the East, and first explicated in the West by Hume. This is the recognition (attained, by Hume and by Buddhist practioners alike, through introspection) that when you look into your self, you find thoughts, perceptions, emotions ... but nothing that you can identify as yourself. On the bundle theory, that's all there is: the self just is the passing show of thoughts, perceptions, emotions ... there's no there, there.
But, Baggini went on, in his book he hadn't just expounded this philosophical idea, he'd gone and talked to philosophers and other thinkers who'd developed it. To clarify the notion of reincarnation, he'd talked to Tibetan lamas who believed that they were reincarnations of identifiable dead people. To investigate the ways in which bodily continuity is important to identity, he'd interviewed people who'd changed sex.
The self, he argues, does exist, but it's not what we take it to be, and it's in this sense that it is an illusion - the ego trick. This seems to me to approach from a different angle the idea that the self is what the Danish science journalist and mathematician Tor Nørretranders has called 'the user illusion', by analogy with the 'desktops' and 'folders' and so on through which we operate computers. We no more see the workings of our minds than we see the workings of our computers. Instead, we see icons on the screen. As one of my characters put it: 'All is analogy, interface; the self itself has windows, the sounds and pictures in our heads the icons on a screen over a machine, the mind.' By windows he, and I, meant Windows.
One of the many interesting aspects of science fiction (SF) is that through it you can not only conduct such philosophical thought experiments, but experience them in imagination, through stories. Someone unfamiliar with SF might be a little taken aback by a novel opening with: 'He woke, and remembered dying.' How (assuming it's intended to be literal) does that even make sense? SF readers, I'm sure, took it in their stride, but it may be worth spelling out the assumptions they'd have brought to the sentence.
In a world where computers are familiar, we know what it means to take a back-up of a computer's memory. Imagine it was possible to take a back-up of the contents of our brains (which it isn't, and may never be, but suppose). What if we were to flip the Locke/Leibniz question, and ask how we'd feel knowing that someone with all our present memories and dispositions, and a body that was a clone of our own, would walk the Earth (or another world) after we had died? Would you think, 'Wow, I'm going to live again!'? Would you think, 'Well, lucky for so-and-so, but that doesn't really help me'? Or would you think: 'Well, that's tough on the poor clone, denied a life of its own and saddled with my memories.'? If we knew we were about to die (but with all our faculties intact) would we feel relieved when the nurse or technician placed the mind-recording apparatus on our brow? Or knowing we'd sensibly made one of our own regular back-ups a couple of weeks ago?
I've imagined these situations, and others yet more bizarre, in that novel (The Stone Canal) and later in Newton's Wake, and of course I'm not the only one and far from the first. I don't know of an earlier example than John Varley's The Ophiuchi Hotline (1977) but there must be some. In another medium, other questions of identity are played with in the film Total Recall, based on a Philip K. Dick story. don't let Arnie's muscles fool you: that film is worth a philosophy seminar. Years ago I and my daughter had a long discussion of it on the bus, and some of the conclusions we came to went into my novel.
My daughter was with me at Baggini's session - we're both big fans of his books - and we posed some of these questions to him at the signing. He answered helpfully and cheerfully, and sent us away still talking. I hadn't asked him the question I should have, about the bundle theory. The first time I looked at my daughter, when she was less than an hour old, I was sure there was a person looking back, and I'm sure it's the same person still. But I didn't ask how that could be.
Born in Stornoway, Isle of Lewis, Ken has been a full time writer since 1997 authoring thirteen novels, including The Star Fraction (1995) and Intrusion (forthcoming, 2012), plus many articles and short stories. His novels and stories have received three BSFA awards and three Prometheus Awards, and several have been short-listed for the Clarke and Hugo Awards. In 2009 he was a Writer in Residence at the ESRC Genomics Policy and Research Forum. Learn more from Ken’s blog The Early Days of a Better Nation