书桌上不能有太多的书，心中则不能少书；这就好像鱼离了水则干枯，心中没有书则无寄托。

The key to credible causal inference is not just the method, but how well the method fits the question at hand.

永远不要低估坚持的力量。大多数人放弃得太早。

There is no such thing as great wisdom in the world, just as there is no such thing as talent. What exists is triviality. If you keep doing repetitive things, you become an expert; if you do repetitive things with special focus, you become a master.

过去是一个拒绝离去的幽灵。