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Commit to your business. Believe in it more than anybody else. I think I overcame every single one of my personal shortcomings by the sheer passion I brought to my work.

我一直是一個斗士，而且我將永遠是一個斗士。

數學是給不同事物以相同名稱的藝術。

自然實驗可以為經濟問題提供有價值的見解。