Introduction : Understandings, politics, and institutions -- I: Socialism as a self-fulfilling prophecy : the party's project. From Marx to conscious social transformation ; Aporias of producing right consciousness -- II: Contingencies and dynamics of understanding : the theory. Constituting understandings through validations ; Dialectics in spaces of validation -- III: Becoming socialist men : the Stasi officers. Guardians of the party state ; Stasi culture : authority, networks, and discourses -- IV: Disenchantment, disengagement, opposition : the dissidents. When someone's Eden becomes another's purgatory ; Forming groups, organizing opposition -- V: Policing understandings : reproducing misunderstandings. Attempting to know and control the opposition -- Conclusions : Paralyzing uncertainties.