In his study of the origins of the prison, Discipline & Punish: The Birth of the Prison, Michel Foucault explored the invention of the Panopticon, a way for a guard to see others without being seen himself.
Bentham’s Panopticon is the architectural figure of this composition. We know the principle on which it was based: at the periphery, an annular building; at the centre, a tower; this tower is pierced with wide windows that open onto the inner side of the ring; the peripheric building is divided into cells, each of which extends the whole width of the building; they have two windows, one on the inside, corresponding to the windows of the tower; the other, on the outside, allows the light to cross the cell from one end to the other. All that is needed, then, is to place a supervisor in a central tower and to shut up in each cell a madman, a patient, a condemned man, a worker or a schoolboy. By the effect of backlighting, one can observe from the tower, standing out precisely against the light, the small captive shadows in the cells of the periphery.
He is seen, but he does not see; he is the object of information, never a subject in communication.
This permanent visibility became a way to exercise power and in so doing induce “in the inmate a state of conscious and permanent visibility.” Foucault writes:
Bentham laid down the principle that power should be visible and unverifiable. Visible: the inmate will constantly have before his eyes the tall outline of the central tower from which he is spied upon. Unverifiable: the inmate must never know whether he is being looked at at any one moment; but he must be sure that he may always be so. In order to make the presence or absence of the inspector unverifiable, so that the prisoners, in their cells, cannot even see a shadow …
You need not force, only observe to “constrain the convict to good behaviour, the madman to clam, the worker to work, the schoolboy to application, the patient to observation of the regulations.”
He who is subjected to a field of visibility, and who knows it, assumes responsibility for the constraints of power; he makes them play spontaneously upon himself; he inscribes in himself the power relation in which he simultaneously plays both roles; he becomes the principle of his own subjection.
Eventually guards discovered that, after a period of consistent monitoring and prompt punishment against perpetrators, inmates began to regulate their own behaviour. They couldn't see a guard and yet they were regulated by conscience itself. An external reality had thus become internalized and became habitual.
Discipline & Punish: The Birth of the Prison is a fascinating study into the origins of the prison.