The future of coal lies not in its quantity but in how cleanly and efficiently we can use it.

If you want to see what this nation is all about, you have to ride the rails. Look outside as you speed through, and you’ll find the true face of America.

你永远是一个有价值、值得尊敬的人——不是因为任何人这么说，不是因为你成功了，不是因为你赚了很多钱——而是因为你决定相信这一点，没有其他原因。

Mathematics is an art, and as an artist, you have to be honest with yourself.

Dreams don't run away, it's always ourselves who run away.