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可持續性不僅僅是一個選擇；這是我們對后代的責任。

The right of nature... is the liberty each man hath, to use his own power, as he will himself, for the preservation of his own nature; that is to say, of his own life.

Success comes when preparation meets opportunity.

數學證明的優雅在于其簡潔和清晰。