在数学中，提出问题的艺术必须比解决问题更有价值。

The greatest discovery of my generation is that human beings can alter their lives by altering their attitudes of mind.

"The world is full of obvious things which nobody by any chance ever observes."

"In the end, we are all just stories, and the best we can hope for is to be a good one."

采矿业必须发展以满足不断变化的世界的需求。