Of late, not a few philosophers of mind have, like Dave, been caught in a tidal wave of fascination with this notion called “zombies”. (Actually, it’s more like “the notion we love to hate”.) It seems to have originated in voodoo rites in the Caribbean and to have spread from there to horror films and then to the world of literature. A Web search will quickly give you all the information you want, and most of it is pretty funny.
Basically, a zombie is an unconscious humanoid who acts — oops, I mean “that acts” — as if it were conscious. There’s no one home inside a zombie, though from the outside one might think so. I have to admit, once in a blue moon I’ve run into someone whose glazed eyes give me the eerie sense that there’s no one home behind them. Of course, I don’t take such impressions seriously. Yet for many philosophers, the hollow, glazed-eyes image has turned into a paradigmatic fear, and today there is no paucity of philosophers of mind who find the notion of a zombie not just painfully abhorrent but in fact perplexingly coherent. These philosophers are so troubled by the specter of zombies that they have taken as their sacred mission to show that our world is not the cold and empty Universe Z, but the warm and fuzzy Universe Q.
Now you might say that this whole book buys into the cold, glazed-eyes, zombie vision of human beings, since it posits that the “I” is, when all is said and done, an illusion, a sleight of mind, a trick that a brain plays on itself, a hallucination hallucinated by a hallucination. That would mean that we all are unconscious but we all believe we are conscious and we all act conscious. All right, fine. I agree that that’s a fair characterization of my views. But the swarm of zombie-fearing philosophers all want our inner existence to be richer than that. They claim that they can easily conceive of a cold, icy universe populated solely by nightmarishly hollow zombies, yet not distinguishable in any objective way from our own universe; at the same time, they insist that such is not the universe we live in. According to them, we humans don’t just act conscious or claim to be conscious; we truly are conscious, and that’s another matter entirely. Therefore Hofstadter and Parfit are wrong, and David Chalmers is right.
Well, I think Dan Dennett’s criticism of such philosophers hits the nail on the head. Dan asserts that these thinkers, despite their solemn promises, are not conceiving of a world identical to ours but populated by zombies. They don’t even seem to try very hard to do so. They are like SL #642, who, when imagining what a strange loop would say on looking at a brilliant purple flower, chose the dehumanizing verb “drone” to describe how it would talk, and likened its voice to a mechanical-sounding recorded voice in a hated phone menu tree. SL #642 has a stereotype of a strange loop as soul-less, and that prejudice rides roughshod over the image of perfectly natural, normal human behavior. Likewise, philosophers who fear zombies fear them because they fear the mechanical drone, the glazed eyes, and the frigid inhumanity that would surely pervade a world of mere zombies — even if, only a moment before, they signed off on the idea that such a world would be indistinguishable from our world.
Consciousness Is Not a Power Moonroof
In debates about consciousness, one of the most frequently asked questions goes something like this: “What is it about consciousness that helps us survive? Why couldn’t we have had all this cognitive apparatus but simply been machines that don’t feel anything or have any experience?” As I hear it, this question is basically asking, “Why did consciousness get added on to brains that reached a certain level of complexity? Why was consciousness thrown into the bargain as a kind of bonus? What extra evolutionary good does the possession of consciousness contribute, if any?”
To ask this question is to make the tacit assumption that there could be brains of any desired level of complexity that are not conscious. It is to buy into the distinction between Machines Q and Z sitting side by side on the old oaken table in Room 641, carrying out identical operations but one of them doing so with feeling and the other doing so without feeling. It assumes that consciousness is some kind of orderable “extra feature” that some models, even the fanciest ones, might or might not have, much as a fancy car can be ordered with or without a DVD player or a power moonroof.