Asking the question "What is a zombie?" raises methodological issues which must be addressed before any attempt to answer the question may proceed. For instance, it must be determined what kind of zombie we are trying to define: voodoo zombies, movie zombies, philosophical zombies, some other kind of thing called a "zombie". We might also want to arrive at a definition that covers all these various sorts of zombie. Additionally, we need to concern ourselves with how we should go about determining what a zombie is. We might follow a natural language philosophy, in which case we would replace the question "What is a zombie?" with the semantic question "What do we mean when we say zombie?" We might, on the contrary, decide that we want to determine the deep meaning of the phenomenon of zombies, in which case we replace "What is a zombie" with the structuralist question "What is the cultural function of the zombie?" Both of these questions have empirical, hence verifiable, procedures for persuing their respective questions. We might also pursue a non-verifiable manner of determining what a zombie is. To find out what a movie zombie is, we might ask George A. Romero what he intended his zombies to be. We might also take the tack that the author is unreliable in matters such as this, and so a true revelation of the deep meaning of zombies would require that we ask anyone but the auteur what zombies represent.
One tendency in evaluations of the undead is to discover a political meaning in the zombie phenomenon. In doing so, the intent isn't simply to show that there is a political dimension to zombies, but rather that the political exhausts all the deep meaning inherent in zombies. For a survey of the political analyses of zombie-hood, see Reason Magazine's survey of zombie literature, which covers interpretations of zombies as alienated labor, Vietnam vets, white supremists, consumer culture, and a few more. This follows a tendency in certain circles to see all deep meaning as ultimately political.
David Chalmers goes in a different direction with his discussion of philosophical zombies. Chalmers makes clear that he is not trying to reinterpret the phenomenon of zombies, but rather is merely appropriating the language of zombies to describe something technically different. Thus, while there may be overlaps between philosophical zombies, movie zombies and voodoo zombies, these are not necessarily relevant to the study of zombies that he is pursuing. Which to some extent is unfortunate, since the relationship between philosophical zombies and political zombies is a rich one. There is an apparent connection between zombies as a manifestation of alientated labor, zombies as a manifestation of aliented man, and zombies as beings without interior lives.
Zombies can be defined provisionally as empty vessels into which any sort of meaning may be poured. This is what Descartes does in the Meditations to resolve the problem of other minds which he initially poses. Early in this work, Descartes wonders how he can know that the people around him are indeed real people rather than automata, devices created to emulate human behavior but which have no being other than that of a seeming-nature. Only after proving his own existence, which serves as a ground from which to prove the existence of God, is he able to return to the original problem and declare that other persons most likely do have an interior life like his because they outwardly behave as he does, and that God would not create a world in which an appearance such as this is not accompanied by a similar reality. God is not a deceiver.
God has been pronounced dead in the intervening years, and so we are left with various problems we once thought resolved. The notion of a natural political order upon which democracies such as the United States were founded have fallen aside in His wake. Without a ready repository of pre-determined meanings founded on religion, modern man is left unmoored and in search for relevance. Once apparently settled by Descartes, the problem of other minds rises from the dead to trouble us once more, and the attempt to unravel the meaning of the Zombie is entangled with the attempt to unravel the meaning of our own existence.