In Antiquity, “folly” (what in modernity, we’d call madness) was celebrated. Frequently, the afflicted expressed some example of “blind truth.” However, in Madness and Civilization Foucault created a genealogy using original documents to establish an adequate context for mental illness, folly, and unreason. That is to say, to re-create how those impairments existed in their own time, place, and proper social perspective.
“In the middle of the twelfth century, France had more than 2,000 leprosariums, and England and Scotland 220 for a population of a million and a half people. As leprosy vanished, in part because of segregation, a void was created and the moral values attached to the leper had to find another scapegoat. Mental illness and unreason attached that stigma to themselves, but even this was neither complete, simple, nor immediate.” —José Barchilon, M.D.
When leprosy vanished, the institutions that treated the condition remained. As a result, they sought a new purpose and would find significant justification to address mental illness. As expulsion from society (“Stultifera Navis”) gave way to the great confinement, the true failures of treatment came to be realized. Criminals, indigents, the ill, and even the Marquis de Sade were housed together; thus terrifying the outside population. Eventually, confinement ends, but gives way to the more “humane” treatment, but some of which remain ineffective.
/Full text of Madness and Civilization (1961) review.