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The search for meaning is a futile endeavor.

Don't walk behind me; I may not lead. Don't walk in front of me; I may not follow. Just walk beside me and be my friend.

Coal’s future depends on our ability to make it cleaner and more efficient.

"Sometimes the hardest journeys are the ones that take you back to yourself."

科學是關于在知識和技術上突破界限。