Madness and Civilization explores the changing relationship between madness and unreason. The true nature of both terms is rarely expressed or allowed to speak, and frequently one forms part of the other. Unreason is defined as “reason dazzled” or confused in the period of confinement. In the modern period, however, unreason is pushed further beneath the surface of society, and is understandable only through certain artists; madness on the other hand, becomes mental illness, and is treated and controlled by medical and psychiatric practices. Unreason is somehow lost after the 18th century, a loss that Foucault laments.