The purpose of life is not to be happy. It is to be useful, to be honorable, to be compassionate, to have it make some difference that you have lived and lived well.

智者抵抗快乐，愚者成为快乐的奴隶。

The beauty of a mathematical proof is in its elegance and the way it reveals the underlying truth in a clear and concise manner.

小说是一台思考的机器，是一种无需离开椅子就能探索世界的方式。

The truth is, the world is so constructed that if you wish to enjoy its fruits, you must submit to its rules.

I would not dare to say that there is a direct relation between mathematics and madness, but there is no doubt that great mathematicians suffer from maniacal characteristics.

埃尔德什差异问题让我着迷，因为它陈述起来如此简单，但含义却如此深刻。