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永遠不要停止學習，因為世界從未停止變化。

It seems to me that if you or I must choose between two courses of thought or action, we should remember our dying and try so to live that our death brings no pleasure to the world.

Certification schemes are the floor, not the ceiling of responsible forestry practice.

成功的真正標準不僅僅是利潤，還有我們留下的積極影響。

寫作是一種愛的行為，一種接近他人、理解他人的方式。

快樂不是一件自我存在的東西，它僅是與其他不快樂事情的一個相對比照，這就是快樂的整個情況。

記憶是一件復雜的事情，是真相的親戚，但不是它的雙胞胎。

The only way to learn a new programming language is by writing programs in it.

We are like travelers who have lost their way； we must ask， each one， for directions from a passerby.

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