Tags:
Journalism of Courage
The revenge of the zombies
To evoke zombies, Searle instructs, "always think of (the thought experiment) from the first-person point of view." Searle’s 1992 evocation illustrates the procedure. As stage setting, suppose that doctors gradually replace your brain with silicon chips, perhaps to remedy its progressive deterioration. From here, conjure yourself a zombie by imagining as follows:
As the silicon is progressively implanted into your dwindling brain, you find that the area of your conscious experience is shrinking, but that this shows no effect on your external behavior. You find, to your total amazement, that you are indeed losing control of your external behavior… (You’ve gone blind but) you hear your voice saying in a way that is completely out of your control, "I see a red object in front of me…" Imagine that your conscious experience slowly shrinks to nothing while your externally observable behavior remains the same.
No sooner are such zombies conjured, of course, than they’re off on their destructive rampage against behaviorism: "We imagined… the behavior was unaffected, but the mental states disappeared." And again, there seems to be no way to stop them before they transmogrify. Suppose besides maintaining behavior that the replacement chips implement the same programs, maintaining the same functional relations as the neurons replaced. There goes functionalism. As for identity theory… suppose the medical doctors are powerless. You are desperate. You have heard of a certain witch doctor. You fly to a remote isle, voodoo rites are enacted, and voila. The deterioration of your brain is magically reversed. It functions physically (chemically, electrically, etc.) just as before.
"To the amazed medical doctors back at the clinic, your brain is indistinguishable from your very own pre-deteriorated brain. But wait! As your brain is being magically restored… it’s just as before. Your conscious experience slowly shrinks to nothing. There goes identity theory. Zombies ate its brain.
Against Searle’s zombie, Daniel Dennett proposes a line of defense or rather prophylaxis. Searle’s evocation, Dennett complains, is "only one of the logically possible interpretations" of the experiment. "The other," Dennett asserts, "is the crucial one: while you… are dying, another consciousness is taking over your body. The speech acts you faintly hear your body uttering are not yours, but they are not nobody’s!"
Where Searle conjures zombies, Dennett imagines multiple personalities. While yours fades out, an alien one (not a zombie) fades in. Unfortunately, this won’t do. Zombies (as Bringsjord points out) easily breach this Dennettian line. To be "one of the logically possible interpretations" is still to be a logically possible interpretation: just Searle’s point. As logical possibilities, it seems zombies can’t be prevented. Once loosed, they can’t be stopped before they transmogrify. Good zombies to the rescue.
The author teaches the philosophy of mind at Michigan State University. The complete paper is at members.aol.com/lshauser/zombies.html
