"Do 'folk concepts' of the mind have anything to do with what really happens in the brain?''

When we speak about our experiences, we use terms like emotion, perception, thought, action, motivation, attention, free will. And these concepts have been the starting point for research and speculation about the brain. But now the evidence is starting to mount that our categories don't fit what's really going on, as far as we can measure and describe. It may turn out that the differences between a thought and an emotion, a perception and an action, a mood and a belief, are part of our tradition of "folk psychology" — the things we tell ourselves to explain the world in ordinary conversation.

For hundreds of years the pattern in science has been to overturn folk concepts, and it seems to me the brain may be the next field for such a conceptual revolution. It may be that in a hundred years people will speak of free will, or the unconscious, or emotion, in the way that we now speak of "sunrise" or "forever" — words that serve for day-to-day talk, but don't map reality. We know the sun doesn't rise because it is the earth that moves and we know that humanity and its planet and the universe itself won't last forever. I see signs that concepts of the mind are due for the same sort of revision. And so that's the question I keep returning to.

David Berreby writes about science and culture, His work has appeared in The New York Times Magazine, The New Republic, Slate, The Sciences and many other publications.