Out of curiosity, how does Moody convince himself that he has devised a decent argument? Moody goes wrong in unwittingly equivocating, repeatedly, between human concepts expressible via ordinary English and the neologisms he invents for denoting terms used by zombies. He trades on the near-irresistable temptation to read into a term at least part of the meaning of u; the reader sees , but unavoidably thinks, at least in part, u. There are many instances of the fallacy of equivocation in Moody's paper; I cite but one here. Moody writes:
Consider the phenomenon of dreaming. Could there be a cognate concept in zombie-English? How might we explain dreaming to them? We could say that dreams are things that we experience while asleep, but the zombies would not be able to make sense of this.The fact is, we couldn't explain, not even in principle, anything to a zombie. This is because if one explains p to x, then x must grasp or understand p, but grasping or understanding requires being conscious. A rock will never grasp anything; it would be perverse to ask how we might explain dreaming to a slab of granite. Yet zombies are, by definition, no more ``alive on the inside" than a rock.
Of course, Moody himself, earlier in paper, says that zombies can't understand anything; he says they merely understand. But saying this camouflages the fact that rocks can also understand. The only difference between a rock and a zombie is that the functions governing their behavior differ. This point can be made vivid via the well-known concept of arbitrary realization. It has been known for decades that a suitably configured abacus can compute all functions a computer can compute ; and rocks and wire can obviously be used to instantiate an abacus. It follows from this and the view that the information processing taking place in zombies is a matter of computation that zombies are in principle no more than encased rocks moving as in an abacus. The point here is not to recapitulate the controversial arbitrary realization argument (according to which consciousness can't be computation because rock and wire in motion can't be conscious; see ); the point is that rocks and wire moving so as to give rise to overt behavior like ours without any consciousness in the picture is, by hypothesis, what we are considering. To innoculate ourselves against Moody smuggling in the familiar meaning of u when he presents , we need to think of nothing more than well-behaved rock. So, for example, when Moody says that ``we can easily imagine the parallel case of the zombie-philosophers wondering whether our consciousness-talk is evidence of something other than mere consciousness," we will be sure to imagine not something like what humans feel when wondering about the strange states of mind mystics enter, but rather rocks moving mindlessly around so as to produce communication in which the symbol `wondering' appears.