The Conscious Mind: In Search of a Fundamental Theory
Traditionally in the philosophy of mind there is supposed to be a basic distinction between dualists, who think there are two fundamentally different kinds of phenomena in the world, minds and bodies, and monists, who think that the world is made of only one kind of stuff. Dualists divide into “substance dualists,” who think that “mind” and “body” name two kinds of substances, and “property dualists,” who think “mental” and “physical” name different kinds of properties or features in a way that enables the same substance—a human being, for example—to have both kinds of properties at once. Monists in turn divide into idealists, who think everything is ultimately mental, and materialists, who think everything is ultimately physical or material.
I suppose most people in our civilization accept some kind of dualism. They think they have both a mind and a body, or a soul and a body. But that is emphatically not the current view among the professionals in philosophy, psychology, artificial intelligence, neurobiology, and cognitive science. Most of the people who work in these fields accept some version of materialism, because they believe that it is the only philosophy consistent with our contemporary scientific world view. There are a few property dualists, such as Thomas Nagel and Colin McGinn, but the only substance dualists I know of are those who have a religious commitment to the existence of a soul, such as Sir John Eccles, a prominent British neurophysiologist.
But materialists have a problem: once you have described all the material facts in the world, you still seem to have a lot of mental phenomena left over. Once you have described the facts about my body and my brain, for example, you still seem to have a lot of facts left over about my beliefs, desires, pains, etc. Materialists typically think they have to get rid of these mental facts by reducing them to material phenomena or by showing that they don’t really exist at all. The history of the philosophy of mind over the past one hundred years has been in large part an attempt to get rid of the mental by showing that no mental phenomena exist over and above physical phenomena.
It is a fascinating study to try to trace these efforts, because typically their motives are hidden. The materialist philosopher purports to offer an analysis of the mental, but his or her hidden agenda is to get rid of the mental. The aim is to describe the world in materialist terms without saying anything about the mind that does not sound obviously false. That is not an easy thing to do. It sounds too implausible to say right out that pains and beliefs and desires don’t exist, though some philosophers have said that. The more common materialist move is to say, yes, mental states really do exist, but they are not something in addition to physical phenomena; rather they can be reduced to, and are forms of, physical states.
The first …
‘Consciousness and the Philosophers’: An Exchange May 15, 1997