Psychons and Intentyons, Part 1: Chalmers' Challenge

In "The Conscious Mind", David Chalmers presents a fascinating argument against interactionism.  In my next few posts, I want to respond to Chalmers' argument.  Meanwhile, here is the argument for your perusal:

In any case, all forms of interactionist dualism have a conceptual problem that suggests that they are less successful at avoiding epiphenomenalism than might seem; or at least they are no better than the view I have advocated...Imagine (with Eccles) that psychons in the nonphysical mind push around physical processes in the brain, and that psychons are the seat of experience.  We can tell a story about the causal relations between psychons and physical processes, and a story about the causal dynamics among psychons, without ever invoking the fact that psychons have phenomenal properties.  Just as with physical properties, we can imagine subtracting the phenomenal properties of psychons, yielding a situation in which the causal dynamics are isomorphic.

(Page 156)