The mind-body problem has been called the greatest question in the history of human thought. It can be phrased as, "How does the physical brain give rise to the psychological mind?"
This question was first widely investigated by Descartes, who intending to extend mathematical methods to all areas of human knowledge, discarded the authoritarian systems of the scholastic philosophers and began with universal doubt. Only one thing cannot be doubted: doubt itself. Therefore, the doubter must exist. This is the kernel of his famous assertion Cogito, ergo sum [I think, therefore I am]. From this certainty Descartes expanded knowledge, step by step, to admit the existence of God (as the first cause) and the reality of the physical world, which he held to be mechanistic and entirely divorced from the mind; the only connection between the two is the intervention of God. This is a formulation of dualism. Dualism, in philosophy, explains all phenomena in terms of two distinct and irreducible principles, such as mind and matter.
Dualism was contested by Descartes's contemporary Thomas Hobbes. He claimed that mental states were just particular physical states. Hobbes's argument for this was succinct. Plainly, mental events and bodily motions interact causally; since only bodily motions can cause and be caused by other bodily motions, mental events themselves must be bodily. This doctrine is known as materialism.
These two traditional theories, dualism and materialism, still dominate discussion of the mind-body problem.
The connection between the mind-body problem and the future of Neuromancer may not be obvious. In order for a computer to interface with the mind--via the brain--as in Neuromancer, must the connection between the mind and the brain must be understood? If dualism is correct, is the future depicted in Neuromancer is impossible? What if materialism is correct? If the mind could be explained in terms of the brain, does there exist hope that that connection could be manipulated to produce a desired result?