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Every problem in mathematics is a puzzle waiting to be solved, and the joy is in the solving.

"We perceive not objects, but their utilities."

The pursuit of science is not a luxury but a necessity for the survival of mankind.

在這個喧囂的世界里，一本書可以是一個安靜的角落。

Every life is in many days, day after day. We walk through ourselves, meeting robbers, ghosts, giants, old men, young men, wives, widows, brothers-in-love, but always meeting ourselves.