The exemplary manifestation of disciplinary power is the prison. For Foucault, the important thing about this institution, the most ubiquitous site of punishment in the modern world (but practically non-existent as a form of punishment before the 18th century), is not the way in which it locks up the criminal by force. This is the sovereign element that persists in modern prisons, and is fundamentally no different from the most archaic forms of sovereign power that exert violent force over the criminal, the exile, the slave and the captive. Foucault looked beyond this most obvious element in order to see more deeply into the elaborate institution of the prison. Why had the relatively inexpensive techniques of torture and death gradually given way over the course of modernity to the costly complex of the prison? Was it just, as we are wont to believe, because we all started to become more humanitarian in the 18th century? Foucault thought that such an explanation would be sure to miss the fundamental way in which power changes when spectacles of torture give way to labyrinthine prisons.
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Foucault argued that if you look at the way in which prisons operate, that is, at their mechanics, it becomes evident that they are designed not so much to lock away criminals as to submit them to training rendering them docile. Prisons are first and foremost not houses of confinement but departments of correction. The crucial part of this institution is not the cage of the prison cell, but the routine of the timetables that govern the daily lives of prisoners. What disciplines prisoners is the supervised morning inspections, the monitored mealtimes, the work shifts, even the ‘free time’ overseen by a panoply of attendants including armed guards and clipboard-wielding psychologists.
Importantly, all of the elements of prison surveillance are continuously made visible. That is why his book’s French title Surveiller et punir, more literally ‘Surveil and Punish’, is important. Prisoners must be made to know that they are subject to continual oversight. The purpose of constant surveillance is not to scare prisoners who are thinking of escaping, but rather to compel them to regard themselves as subject to correction. From the moment of morning rise to night’s lights out, the prisoners are subject to ceaseless behavioural inspection.