Recently I was happily reintroduced to the concept of the philosophical zombie (p-zombie to its friends) when listening to the Guardian's Science Weekly interview with Susan Blackmore, psychologist, "memeticist," and, it turns out, Hildabeast. She's recently written a book called Conversations on Consciousness, which may find its way into my book review soon. She's also the author of Consciousness: A Very Short Introduction and of course The Meme Machine.
Here's how Blackmore describes the p-zombie in the Guardian interview:
...the philosopher zombie is an old idea - been around in philosophy for a long time. It's this idea: Let's suppose that there's a... Ed sitting there, there you are, and there's another one next to you that looks exactly the same and behaves exactly the same and he's in every possible way indistinguishable from the outside. But, it's a zombie; it's all dark inside, it's not having any experiences at all! The zombic hunch is the idea that that would be possible. You could build such a thing, you know, with chips inside, or I don't know, have a strange mutation or something or another.Now I'm really regretting not ever having heard Daniel Dennett lecture about zombies, because I'm only now faced with the fact that I might not actually believe in zombies, or at least in p-zombies. Has thinking this thought resulted in a zombie, somewhere out there, falling down dead? (Or was it dead already? What about those pregnant zombies? Isn't that impossible? But I digress...)
If you believe that such a philosopher zombie is possible, then you must believe that consciousness is some kind of added extra that's sort of been taken out of the zombie and is put into us at some point or has evolved for some purpose or has some function or whatever. On the other hand, you might argue, well that that's simply impossible, an intelligent creature that would act like you, with all of the subtleties and nuances of the way you behave would have to be conscious because consciousness is just what it means to be that kind of creature.
Fortunately, those blank-faced, ravenous-for-blood, I'm-gonna-eat-your-brains sorts of zombies are a far cry from p-zombies. After all, the zombies of 28 Days Later and 28 Weeks Later are the result of a virus using humans to spread itself around, which provides a pretty clear material difference between the brains of the conscious survivors and the unconscious (and non-p) zombies. Come to think of it, this virus may not be so different from the Lancet Fluke, which causes ants, once infected, to climb up blazes of grass so that they'll be eaten by cows or sheep, moving the parasite on to the next part of its lifecycle. This is one of Dennett's favorite metaphors for - you guessed it - memes (see how everything comes full circle?), and more specifically, religion (more on that soon).
The pictures in this post are from the Zombie Flashmob in San Francisco, a tradition (dare I say meme?) which I'm happy to report has recently spread to Memphis.