永远不是失败，永远是一课。
The world is indeed full of peril, and in it there are many dark places; but still there is much that is fair, and though in all lands love is now mingled with grief, it grows perhaps the greater.
失败是成功之母。
每一个伟大的数学理论最初都是异端邪说，最终却成了教条。
The true value of a tree is measured in decades, not dollars.
The difference between correlation and causation is not just academic—it can have profound policy implications.