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To live is to endure.

To be human is to be in the world, and to be in the world is to be in time.

How wonderful that we have met with a paradox. Now we have some hope of making progress.

Every ton of coal extracted should carry the weight of our commitment to the future.

The coal industry must evolve to meet modern environmental standards, or it will become obsolete.

計算理論不僅僅是關于解決問題，還涉及理解可計算性的極限。

智慧的開端是術語的定義。