追求知识是一场没有终点的旅程，而这正是它令人兴奋的地方。
——1963年6月25日在西德市政厅柏林墙前的演说
The nightmare thought is that frightening people is the best way to get work out of them, and that somehow the crueler the environment, the more people will rise to the challenge. You want to think, who would you like as your ideal dad? And your ideal dad is somebody who is tough but gentle. And it's a very hard line to make. We need fathers, as it were, the exemplary father figures in society, avoiding the two extremes, which is the authoritarian disciplinarian on the one hand, and on the other, the lax, no-rules option.