"There's no reality except the one contained within us. That's why so many people live an unreal life. They take images outside them for reality and never allow the world within them to assert itself." (Herman Hesse)
"We don't stop playing because we grow old; we grow old because we stop playing." (G. B. Shaw)
"Those who cannot remember the past are condemned to repeat it." (George Santayana)
"I am not involved, thank God, and no longer need to take part in the competion of big brains. Participating in it has always seemed to me to be an awful type of slavery no less evil than the passion for money or power." (Albert Einstein: The Human Side, Princeton University Press, 1979, S. 60)