A prison tower sees every cell, but no inmate can tell if they're being watched

Bentham designed the Panopticon so a single guard could watch any prisoner at any moment, while prisoners could never confirm whether they were actually being observed. Foucault argued this is the model for modern power generally: once you can never be sure you're unwatched, you start disciplining yourself, and the surveillance no longer needs to be real to work.

— Michel Foucault, Discipline and Punish: The Birth of the Prison — 1975
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