Massimo Pigliucci in Scientia Salon:
Philosophy of mind and the nature of consciousness are fascinating topics, which recur both here at Scientia Salon  and at my former writing outlet, Rationally Speaking . And of course we can hardly talk about consciousness for long before running into one of the most famous (and, in my mind, pernicious) thought experiments in philosophy of mind: the philosophical zombie!  (Now you should hear ominously sounding music in the background…)
In this essay I propose to do the following: we are first going to take a look at Chalmers’ zombie argument (one of a number of instances of zombification in philosophy of mind) to see exactly what it says and why I find it utterly unconvincing. Next, we’ll use p-zombies to broaden the discussion to parse the differences among different types of possibilities, especially logical, metaphysical and physical/nomological (with a nod toward two other types: epistemic and temporal/historical/contingent). Finally, we’ll use whatever we think we have learned in the process to talk even more broadly about the very nature of philosophical inquiry — or at the least the sort of analytic-type  metaphysics that Chalmers and his supporters indulge in.
What, if anything, are p-zombies?
The first thing to be aware of when we talk about p-zombies is that the concept has a long history and has been used in different ways for different purposes. It can be traced back to Saul Kripke’s arguments in the 1970s against type-identity theory in philosophy of mind as presented in his Naming and Necessity . Versions of it were elaborated upon during the same decade by both Thomas Nagel and Robert Kirk. But we won’t go into any of that, focusing instead on the more famous Chalmers’ version of 1996.