The Mind–Body Problem

You are, right now, having conscious experiences—the color of this page, a flicker of interest or boredom, the inner feel of following an argument. You are also a physical body, a system of neurons firing in electrochemical patterns. How are these two related? Is the mind just the brain, or something more? This is the mind–body problem, and it sits at the heart of what it is to be human.

Substance dualism

René Descartes gave the classic dualist answer. Using his method of doubt, he found he could doubt the existence of his body but not the existence of himself as a thinking thing—"I think, therefore I am." From this he argued that mind and body are two distinct substances: the mind (res cogitans) is non-extended, indivisible, and essentially thinking; the body (res extensa) is extended in