Stanford Physicalism: Physicalism is the thesis that everything is physical, or as contemporary philosophers sometimes put it, that everything supervenes on the physical. The thesis is usually intended as a metaphysical thesis, parallel to the thesis attributed to the ancient Greek philosopher Thales, that everything is water, or the idealism of the 18th Century philosopher Berkeley, that everything is mental. The general idea is that the nature of the actual world (i.e. the universe and everything in it) conforms to a certain condition, the condition of being physical. Of course, physicalists don’t deny that the world might contain many items that at first glance don’t seem physical — items of a biological, or psychological, or moral, or social nature. But they insist nevertheless that at the end of the day such items are either physical or supervene on the physical. (PDF)
Stanford Zombies: A metaphor of Saul Kripke’s helps to show how the zombie idea threatens physicalism (Kripke 1972/80, 153f.). Imagine God creating the world and deciding to bring into existence the whole of the physical universe. Having created this purely physical universe, did he have to do any more work to provide for consciousness? Answering yes to this question implies there is more to consciousness than the purely physical facts alone can supply. If nothing else, it implies that consciousness depends at least partly on nonphysical properties, ones that would not exist in a purely physical world; it would be a zombie world. Physicalists, on the other hand, are committed to answering no. They have to say that by fixing the purely physical facts, God did everything that was needed to fix the mental facts about the organisms thereby created, including their thoughts, feelings, emotions, and experiences. And if fixing the physical facts is alone enough to fix the mental facts, then it seems that a zombie world is impossible. (PDF)
Levin, Janet (2012) Do Conceivability Arguments against Physicalism Beg the Question? Vol. 40, No. 2, Consciousness (FALL 2012), pp. 71-89: Many well-known arguments against physicalism—e.g., Chalmers’s Zombie Argument and Kripke’s Modal Argument—contend that it is conceivable for there to be physical duplicates of ourselves that have no conscious experiences (or, conversely, for there to be disembodied minds) and also that what is conceivable is possible—and therefore, if phenomenal-physical identity statements are supposed to be necessary, then physicalism can’t be true. Physicalists typically respond to these arguments either by questioning whether such creatures can truly be conceived, or denying that the conceivability of such creatures provides good evidence for their ‘metaphysical’ possibility. An increasing number of physicalists, however, contest these arguments in a different way, namely, by suggesting that the conceivability premises in these arguments beg the question: one’s ability to conceive of the existence of zombies (or disembodied minds) depends exclusively on what one antecedently believes to be the nature of conscious experience (or the theories of consciousness one tacitly accepts)—and therefore cannot legitimately be used to draw conclusions about whether conscious experiences could be physical states or processes. My aim in this paper is to consider, and raise questions about, (various versions of) this response to the antiphysicalist arguments—and argue that physicalists have more promising ways to disarm them.
2. Arguments against physicalism
2.1 The knowledge argument against physicalism
IEP Article on Knowledge Argument against Physicalism. PDF.