Foucault emphasizes that the voices of the mad are silenced in confinement, but that these changes show how powerful their voice can be. Foucault is generally concerned to allow the voices of the confined, prisoners and the mad to be heard.
Changes of confinement are due to two factors: first, a change in the status of madness and second, economic change. It was no longer appropriate for madmen and otherwise sane deviants to be mixed together; therefore madness had to be isolated. It was separated from other social ills to become a special category. The second cause was perhaps the most powerful. In the second section of Madness and Civilization, Foucault explains how confinement was structured by the seventeenth century economic crisis and changing attitudes to labor. The role of confinement within society depended to a great extent on its economic value. When its economic value disappeared, its profile had to change.
Eighteenth century French economic thought replaced the figure of the pauper with two variables. In doing so, it found a new role for poor people. If they could be put to work, then confining them was a mistake. Changes in confinement essentially involved removing certain things from the domain of unreason. Poverty and madness were no longer unreason. Madness was set free because it was no longer seen as something that needed to be confined, even if in practice it was.
The revolutionary reforms that Foucault refers to began by separating madmen from political subversives and counter-revolutionaries in prison. At its center was the idea taken form the Declaration of the Rights of Man that people could only be detained according to the law. According to this notion, criminals should be put in prison, but madmen should be treated. All the other deviants and social undesirables must be set free. This led to certain problems. The position of madness was uncertain. Reforms intended to treat the mad, but no facilities existed for this. Again, Foucault is somewhat cynical about the aim of the reformers. He sees the revolutionary decrees as attempting a difficult restructuring of society, rather than a humanitarian attempt to set people free. Problems with madness and confinement arose from social uncertainty. As society changed, the role of the madman had to change too.
The economic and social explanations for these changes in confinement may surprise some people. Foucault's critics generally accuse him of imposing general, abstract theories and ignoring more practical historical detail. However, he is interested in the systems of knowledge and culture that define and create certain terms and structures; for him, these systems can be economic, political or intellectual. Foucault does not ignore economic and social explanations, even if he views them in different ways to other historians.