How could Germany’s conservative revolutionaries of the Weimar Republic, and later the Nazis, reject the rationalism of the Enlightenment and yet embrace modern technology? Jeffrey Herf examines this paradox in a cultural tradition evident in the writings of some major intellectuals of the Weimar right - Ernst Juenger, Oswald Spengler, Werner Sombart, Hans Freyer, Carl Schmitt, and Martin Heidegger - as well as writings of German engineers both before and after the Nazi seizure of power.