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There are other reasons --There are other reasons why it's perhaps harder now to feel calm than ever before. One of these, and it's paradoxical, because it's linked to something that's rather nice, is the hope we all have for our careers. Never before have expectations been so high about what human beings can achieve with their life span.

物理學的美在于它能夠用簡單而優雅的理論解釋復雜的事物。

邏輯是所有數學推理的基礎。