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Mathematics is not a deductive science—that's a cliché. When you try to prove a theorem, you don't just list the hypotheses and then start to reason. What you do is trial and error, experimentation, guesswork.

戰(zhàn)爭是一種精神現(xiàn)象。

季路問怎樣侍奉鬼神，孔子說：“人都不能侍奉好，還談什么侍奉鬼神？“請問死是怎么回事？“生都不了解，還談什么了解死？”

A story is a way of reclaiming the past.

With a library you are free, not confined by temporary political climates. It is the most democratic of institutions because no one - but no one at all - can tell you what to read and when and how.

在科學(xué)中，我們必須接受我們最珍視的理論可能是錯誤的這種可能性。

To write is to make one's self a echo of the world's soul.