领导的艺术在于说不，而非说是。说是很容易的。
In mathematics, as in life, the most elegant solutions often arise from a deep understanding of the problem.
人是从失败中学习的。
Never forget what you are, for surely the world will not. Make it your strength. Then it can never be your weakness. Armor yourself in it, and it will never be used to hurt you.