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在這片未知的土地上，每一步都帶來新的發(fā)現(xiàn)，而每一個發(fā)現(xiàn)都加深了神秘感。

The process of grouping, of organization, is not arbitrary but follows definite laws.

You have to believe in yourself when no one else does.

Mathematics is not about numbers, equations, computations, or algorithms: it is about understanding.

每本書都是作者和讀者之間的對話。