" If anything proves that the city was primarily a control center, long before it became a center of communication, the persistent restrictions exercised over the extension and communication of knowledge would support this interpretation. As in the United States and Soviet Russia today, the great business of the citadel was to 'keep the official secrets.' These secrets created a gap between the rulers and the ruled that almost turned them into different biological species; and it was not until the achievements of civilization themselves were called into question, by popular revolt, that any part of these secrets was shared. "

― Lewis Mumford , The City in History: Its Origins, Its Transformations, and Its Prospects