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Natural experiments are a powerful tool for understanding causal relationships in the real world.

Don't go around saying the world owes you a living. The world owes you nothing. It was here first.

I’ve learned that pain can be the greatest inspiration.

預測未來的最好方法就是發明未來。

每個人都有感到孤獨的時候。

群眾沒有能力理解復雜的問題。

如果你早上起床，認為未來會更好，那就是美好的一天。否則，就不是。