And when you’re down in the hole， when that moment comes， it’s really okay to feel bad for a little while. Give yourself time to mourn what you think you may have lost but then here’s the key， learn from every mistake because every experience， encounter， and particularly your mistakes are there to teach you and force you into being more who you are. And then figure out what is the next right move.

死亡不是生命的对立面，而是它的一部分。

找到自己的最好方法就是在为他人服务中迷失自己。

数学不仅仅是关于数字、方程、计算或算法：它是关于理解的。

"A picture book is like a small theater."

Curiosity is the engine of intellectual achievement, and humility is its compass.