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"The world is a mirror, and the mirror is a game."

In international trade, a country should specialize in the production of goods for which it has a comparative advantage, and trade with other nations to maximize overall economic welfare.

【釋義】讀書不要拘泥于書上或迷信書，應該加以分析，辨證地去看問題。

There is no such thing as a special category of science called applied science; there is science and its applications, which are related to one another as the fruit is related to the tree that has borne it.

Each success only buys an admission ticket to a more difficult problem.