A philosophical zombie, according to Wikipedia, is a postulate in philosophy concerning entities which are apparently human beings but which have no consciousness. The question, as originally proposed by Thomas Nagel in 1970, defines a p-zombie as a creature with the same behavior as a human, and asks whether there would be any observable difference between the zombie and the normal human.

Dennett, as the debate emerged, objected that by definition the zombie is indistinguishable, since it is defined (by the terms of the question) to have the same behavior.

The question was badly stated. Dennett’s objection confuses the literal terms of the question with its intent. Properly stated, it’s asking whether consciousness makes any difference in observable behavior. On that basis, the answer is Yes, at least some behavior may be notably different; but you have to consider as part of its behavior how it answers questions.

Even if the p-zombie exhibits the same actions as a normal human being, by the terms of the question we know there is at least one difference: the normal human experiences consciousness and the zombie does not. We know that experiences can be described and discussed in the course of a conversation. Questions put to the subject are answered on the basis of his knowledge and experience. Hence we should be able to examine the subject’s experience of consciousness by a suitable discussion, and one thing is a clear: an entity which has never been consciousness will not be able to fake a consistent description of what it’s like to be conscious, whereas a normal person should be able to do it.

This argument is based on the premise that behavior, in the usual sense, is objective and observable, but language exposes subjective beliefs, thoughts, and experience. We can expect, for example, that a zombie would never accept philosophical arguments that consciousness exists, or affects a creature’s behavior — he never experienced it, so as far as the creature knows, there is nothing to which the word “consciousness” corresponds. This is a reasonable explanation for the existence of some philosophers who use a material eliminativist perspective, such as Dennett, the Churchlands, and others. They are human beings, but lack any internal presence of consciousness, so of course they reject theories of its existence.

Of course we would have to be careful of false accusations; we don’t want to start witch hunts. But at least it seems clear that the discussion of zombies has been confused and ineffective, beginning with a poor statement of the question, and by a general failure to recognize that behavior is not the only dimensionality by which we interact with others.

Sometimes we seriously wonder if the whole analytical approach of anglo-american philosophy invites people with some sort of mental distortion. This should have been a simple question.