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我們畫的每一條線都承載著責任。

譯文：即使處在平安的環境，也要時刻想到可能會有突如其來的危險。

It is remarkable how much long-term advantage people like us have gotten by trying to be consistently not stupid, instead of trying to be intelligent.

每個數學問題都有解答；挑戰在于找到它。