The Panopticon is a model for imprisonment popularized by the philosopher Michel Foucault in Discipline and Punish, but Foucault’s 1975 text is influenced by ideas first expressed by British philosopher Jeremy Bentham way back in the 1800s. The Panopticon allows for one centralized guard tower in a rotunda at the center of a circular prison, where all the cells face outward toward the tower. The guard(s) in the rotunda can see out, but the prisoners cannot see in, creating the illusion of constant surveillance.
The design of the panopticon, with the centralized guard-tower, theoretically also allows for surveillance of the guards from the general public, thus solving two problems at once: controlling the behavior of prisoners, and answering the age-old question “who guards the guards?