工具变量的美妙之处在于它们让我们以新的视角看世界。
The beauty of instrumental variables is that they allow us to see the world in a new light.
The only way to deal with an unfree world is to become so absolutely free that your very existence is an act of rebellion.
My biggest opponent is myself.
"We're all just a bunch of guys trying to do something great."
我不需要理由去无畏。