The Conscious Mind is one of those philosophical works that becomes famous because it features interesting arguments in support of implausible conclusions. Chalmers argues for property dualism, the thesis that mental properties are fundamentally different from physical properties. In other words, mental states are not equivalent to, cannot be reduced to, and do not logically supervene on brain states. This is a more plausible view than the traditional dualist claim that there are mental substances (minds or souls) in addition to physical substances, and that the mental and physical substances somehow interact.  

Chalmers agrees that there are psycho-physical laws that relate brain states and mental states, but argues that physical properties and mental properties are ontologically distinct. Maybe this is the correct view, but Chalmers goes further when he begins to discuss a possible fundamental theory of consciousness. He thinks that we should ascribe consciousness to any system that exhibits the same causal relationships as a brain, e.g. automated systems, John Searle’s Chinese Room translation scheme, and Ned Block’s billion minds linked together by radio. Since he views consciousness as a fundamental property of the universe, he thinks that rocks and even sub-atomic particles might possess some simple form of proto-consciousness. He suggests that panpsychism is a real possibility. He also argues that the simplest interpretation of quantum mechanics involves minds branching into other minds, so that each of us is one of a vast set of similar minds, all having split off from our infant selves.

The naturalistic or property dualism that Chalmers advocates, featuring “physical properties, separate phenomenal properties, and a lawful connection between the two”, is certainly worth considering as a philosophical theory of mind. If a property is merely a way of being, maybe mental properties (what it is like to have experiences or to be an X) are fundamentally different from physical properties. However, his views on what systems or objects might be conscious are much less plausible, despite the many ingenious arguments that he offers.  (7/25/11)