Apparently it's World Philosophy Day. Why have a WPD I asked myself, but when I clicked on the link I discovered the answer is only available in French. Ah, the virtuous impenetrability of the academic classes. However, I was pleased to see the BBC covering the conundrum I featured a little while ago, ie is it morally acceptable to harvest human organs from unsuspecting hospital porters?
I thought I'd return the favour and pick up one of their philosophical teasers;
Consider a photo of someone you think is you eight years ago. What makes that person you? You might say he she was composed of the same cells as you now. But most of your cells are replaced every seven years. You might instead say you're an organism, a particular human being, and that organisms can survive cell replacement - this oak being the same tree as the sapling I planted last year.
But are you really an entire human being? If surgeons swapped George Bush's brain for yours, surely the Bush look-alike, recovering from the operation in the White House, would be you. Hence it is tempting to say that you are a human brain, not a human being.
But why the brain and not the spleen? Presumably because the brain supports your mental states, eg your hopes, fears, beliefs, values, and memories. But then it looks like it's actually those mental states that count, not the brain supporting them. So the view is that even if the surgeons didn't implant your brain in Bush's skull, but merely scanned it, wiped it, and then imprinted its states on to Bush's pre-wiped brain, the Bush look-alike recovering in the White House would again be you.
But the view faces a problem: what if surgeons imprinted your mental states on two pre-wiped brains: George Bush's and Gordon Brown's? Would you be in the White House or in Downing Street? There's nothing on which to base a sensible choice. Yet one person cannot be in two places at once.
In the end, then, no attempt to make sense of your continued existence over time works. You are not the person who started reading this article.
To me this is a classic philosophical problem, and I don't mean that in a good way. It's essentially a word puzzle rather than an actually existing difficulty that we need to solve. Whilst the question of what it's acceptable to do, or not do, to save human lives has a direct impact on how we see the world, this question is one of how we construct language.
It's a bit like the old joke where a cleaner proudly boasts that he has been using the same broom for forty years. Every summer he replaces the head and every winter the handle. Ho ho. It's an example of amusing language play, which has its place, but doesn't get us far when exploring genuine ethical issues.
Now, it can be fascinating to think about the implications when someone has their brain wiped, which does seem particularly plausible in reference to Mr Bush, but I suspect that what we're grappling for here is an understanding of the soul in a secular context. It's futile to look for an objectively accurate definition of what a person is and is not because it can only exist in the sense of a shared subjective understanding of what we take to be a person.
The term used in the academic world is ontology, which has no translation into normal English precisely because it's a concept of little or no use to anybody. However, in this context it means that the problem rests on the idea that you exist as a clearly delineated thing and so we have to work out where your "edges" are. That if you look at an atom in the universe it will either be part of you or not be part of you. That's quite an assumption to make to my mind.
Because I have a large bag of skin that contains liver, kidneys, bones, stomach, etc. it allows us to create the category "me" to describe that bag and the things it gets up to - but it doesn't mean that the universe cares whether my spleen is part of what defines me because 'me' is just a working definition for a series of phenomena.
"I" am completely integrated into the world and yet because the world isn't grey goo but divided into distinct parts, it allows us to come up with the term "I" to help us understand what's going on around us. Just as we see a clock as a thing, but it has parts we can label that have particular properties. Snap the second hand off and we still have a clock but the second hand is now just a slender piece of plastic definable only in relation to the social function it once fulfilled.
These kinds of discussion are, I think, useful - but mainly in helping us to understand what bits of philosophy have some kind of utility for us and which are simply amusements, like a crossword, good as a mental workout but fairly irrelevant whether we complete the problem, get half way or never pick up the pen at all.