The true challenge in mathematics is not solving problems, but asking the right questions.

Sometimes we get sad about things and we don’t like to tell other people that we are sad about them. We like to keep it a secret. Or sometimes, we are sad but we really don’t know why we are sad, so we say we aren’t sad but we really are.

The fear of death follows from the fear of life. A man who lives fully is prepared to die at any time.

HUMILITY. Imitate Jesus and Socrates.

被遗忘比死亡更糟糕。

人类活动正在成为一种强大的地质力量。

圣人与物相处而不伤害，不伤害外物的，外物也不伤害他。正因为无所伤害，才能自然地与人交往。山林啊，大地啊，都能使我欣然快乐。