'What is your name?' 'Damien Broderick.' 'IT DOESN'T MATTER WHAT YOUR NAME IS!!!':
> But this is just the auto-deconstruction of the very concept `zombie' that
> undoes the whole thought experiment. As people have noted for years, it's
> like proposing a universe exactly like ours where molecules bash against
> each other but there is no `heat'.
I formulated the thought experiment this way to throw the idea of "qualia" into doubt. In fact, many (most?) philosophers of mind who believe in qualia ALSO believe that zombies could exist, or, at least, that they are conceptually coherent.
For, if there are "qualia," in the Chalmers-esque sense of the word, then there could, at least conceptually, exist something that was physically and functionally identical to something which had qualia, but which didn't have qualia. The term "zombie," for those who don't know, is actually a technical term in the philosophy of mind, and it is just that very thing described above.
The possibility, at least in principle, of there being a "zombie" is the sort of argument mustered by all sorts of misguided philosophers who think that there is some spooky thing that a zombie could lack but that we have. Here's Chalmers using this exact argument:
"At the end of the day, the same criticism applies to *any* purely physical account of consciousness. For any physical process we specify there will be an unanswered question: Why should this process give rise to experience? Given any such process, it is conceptually coherent that it could be instantiated in the absence of experience. It follows that no mere account of the physical process will tell us why experience arises. The emergence of experience goes beyond what can be derived from physical theory."
These philosophers are trying to say: Look, we KNOW we have consciousness. So why should any particular physical process yield it? It is intended to show that there is something, consciousness, which exists, but entirely apart from physically observable causes and effects.
That "instantiation in the absence of experience" is, technically, a zombie, and it must be true that zombies are conceptually coherent in order for qualia to exist at all. For, if zombies cannot exist, then it doesn't make sense for there to be any difference between us and a zombie. Since the only difference between us and a zombie is qualia, if there is no difference between us and a zombie, then there's no difference between having qualia and not having qualia.
As Dennett, the dyed-in-the-wool functionalist, puts it in response to zombies: "Do you know what a zagnet is? It is something that behaves exactly like a magnet, is chemically and physically indistinguishable from a magnet, but is not really a magnet! (Magnets have a hidden essence, I guess, that zagnets lack.) Do you know what a zombie is? A zombie is somebody (or better, something) that behaves exactly like a normal conscious human being, and is neuroscientifically indistinguishable from a human being, but is not conscious. I don't know anyone who thinks zagnets are even "possible in principle", but Nagel and Searle think zombies are. Indeed, you have to hold out for the possibility of zombies if you deny my slogan [that, "once you have explained everything that happens, you have explained everything"]. So if my position is behaviorism, its only alternative is *zombism*." (his emphasis)
--Dennett, "Back from the Drawing Board," http://ase.tufts.edu/cogstud/papers/backdraw.htm
--- My argument is simple: Most people have an extremely primitive reason for believing in qualia. They take it to be undeniable, directly accessible, etc. But if they could, at least conceptually, BE a zombie, then the idea of qualia *is* deniable. We could ALL be zombies, all totally lacking in qualia, yet "thinking" (at least in a functionalist sense) that we do. Since accepting the idea of qualia requires us to believe that a zombie could, at least conceptually, exist, then unfortunately it also requires us to conclude that we can't be so sure that we have qualia at all. What makes this argument hard to shake is the fact that if you reject the possibility of zombies, you ALSO reject the possibility of qualia. For, if the only argument for the existence of qualia is that it somehow "feels that way," then someone's making a very important mistake: you could well NOT have any such feelings, but still think that you do.
> Damien Broderick (AND IT FUCKING WELL DOES MATTER WHAT MY NAME IS)
Well, I put it in quotes, after all. ;) Instant poll: (please reply in private, unless you feel like you want to share with the list) It's just one line. Is it really THAT annoying? I find it funny, and I DON'T take it seriously. -Dan -unless you love someone- -nothing else makes any sense- e.e. cummings