In the era of cybernetics, architects were confronted with a new operational possibility space created by technical systems, methods, and processes. Design processes were reduced from their creative nature to scientific problem-solving methods. Buildings were calculated using circuit diagrams and feedback loops; floor plans and designs were no longer sketched by hand but produced by a computing machine. The significance of creativity and imagination was juxtaposed with the technical intelligence of electronic brains and thinking machines. Thus, the image of the architect in his traditional role as an intuitive designer, creator, and demiurge was placed in the crosshairs of cybernetics. It was a matter of nothing less than the survival of his authorship in an advanced techno-scientific world. The era of cybernetics is presented in this context.