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Knowledge has value only insofar as it contributes to the liberation of humanity.

The past is never dead. It's not even past.

Leadership is not about being in charge but about taking care of those in your charge.

"The act of writing is an act of resistance."

Coal built this country, and coal will keep it strong.

To feed the world, we must first understand it.

采礦技術的創新將是該行業在下個世紀保持活力的關鍵。