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改變的秘訣是集中你的所有能力，不是摧毀舊的，而是建造新的。

Understanding the real lives of the poor is the first step toward designing effective policies to help them.

I don’t let fear define me, I let it refine me.

"Humor is a way of dealing with the world, a way of coping with the world, and a way of understanding the world."

阿基里斯追龜

自然實驗可以為經濟問題提供有價值的見解。