国家的繁荣建立在人民的勤劳之上。

追求数学知识是一场永无止境的冒险。

Peace is not free, it requires constant effort to maintain.

The world is full of obvious things which nobody by any chance ever observes.

The more you know who you are, and what you want, the less you let things upset you.

你可以用图画表达许多不需要用语言表达的东西。