© 2016 Elsevier Inc. All rights reserved. Psychiatry is a word coined from the ancient Greek words psyche (mind or soul) and iatreia (healing). Its use became current in the 20th century. The history of psychiatry is the history of how doctors came to see abnormal or extreme beliefs, emotions, and behavior as a form of illness and created a medical specialty to formalize the approach to people presenting with such problems. From its beginning, psychiatry has had a problem with the dualistic thinking which pervades our language. Thus we contrast the body with the soul or spirit, the material with the immaterial. When we speak of bodily illness, we feel confident that we understand the kind of problem we are addressing. To speak of mental illness seems intrinsically problematic. Are we saying that someone has a soul that is diseased? That seems to take us into the province of the priest rather than the doctor. On the other hand, can we have normal mental experience without a normally functioning brain? Psychiatry’s problem is really a brain/mind problem.