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數(shù)學研究是一次進入未知的旅程，每一次發(fā)現(xiàn)都為新的謎題打開了大門。

I am not young enough to know everything.

The most profound ideas in mathematics often arise from the simplest observations.

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.

過去并未死去，它甚至還未過去。

有些人自以為是，不知天高地厚，也未必是道德問題，而是因為他見識太少，經(jīng)歷太少。