
Die offene Gesellschaft und ihre Feinde. Mohr, 7. Auflage 1992, Tübingen, S. 224 books.google https://books.google.de/books?id=0NMKZ_TznK8C&pg=PA224
"We must plan for freedom, and not only for security, if for no other reason than only freedom can make security more secure." - The Open Society and Its Enemies. books.google http://books.google.de/books?id=yPcHAQAAIAAJ&q=must+plan
The Open Society and Its Enemies (Offene Gesellschaft) (1945, engl.)