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數學不是關于數字、方程、計算或算法的：它是關于理解的。

The death of a beautiful woman is, unquestionably, the most poetical topic in the world.

幸福就是珍惜小事。

置身于是非之外，評斷是非才能客觀；置身于利害之外，才能看清利害的變化。

I never know what I think about something until I read what I've written on it.

寫作是作證。