Sometimes it's the journey that teaches you a lot about your destination.

The future of the coal industry lies in cleanliness, low-carbon, and intelligence.

"You can't do anything about the length of your life, but you can do something about its width and depth."

If you're not stubborn, you'll give up on experiments too soon. And if you're not flexible, you'll pound your head against the wall and you won't see a different solution to a problem you're trying to solve.