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Data are profoundly dumb; they tell you nothing about causes and effects.

可持續性不僅僅是一個目標，更是我們共同的責任。

It is better to be a human being dissatisfied than a pig satisfied; better to be Socrates dissatisfied than a fool satisfied.

Trade between two countries can be mutually beneficial, even if one of them is less efficient in the production of all commodities.

The value of a commodity, or the quantity of any other commodity for which it will exchange, depends on the relative quantity of labor which is necessary for its production, and not on the greater or less compensation which is paid for that labor.