Z is keep your mouth shut. Nationalism is an infantile sickness. It is the measles of the human race. Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. All these aspirations are directed toward ennobling man's life, lifting it from the sphere of mere physical existence and leading the individual towards freedom.
Imagination is more important than knowledge.
Knowledge is limited. Imagination encircles the world. One should guard against preaching to young people success in the customary form as the main aim in life. The most important motive for work in school and in life is pleasure in work, pleasure in its result, and the knowledge of the value of the result to the community.