Here’s an excerpt:
The guiding obsession of [the Churchlands’] lives is an ancient philosophical puzzle, the mind-body problem: the problem of how to understand the relationship between conscious experience and the brain. Are they different stuffs: the mind a kind of spirit, the brain, flesh? Or are they the same stuff, their seeming difference just a peculiarly intractable illusion? And if they are the same stuff, if the mind is the brain, how can we comprehend that fact? What can it possibly mean to say that my experience of seeing blue is the same thing as a clump of tissue and membrane and salty liquid?
(Via Lieter Reports.)