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書籍是一種政治行動。書籍是知識。書籍是反思。書籍改變你的思想。

在數學中，旅程與目的地同樣重要。

The whole conviction of my life now rests upon the belief that loneliness, far from being a rare and curious phenomenon, peculiar to myself and to a few other solitary men, is the central and inevitable fact of human existence.

Change is hard, but it is necessary for progress.

好的市場設計能讓個人激勵與社會效率保持一致。