I am always glad to think that my education was, for the most part, informal, and had its roots in the soil.

I never saw a problem that I did not attempt to solve by mechanical means.

Sustainability isn't a cost center; it's the future of our industry.

我们现代的头骨里装着一个石器时代的心智。

The coal industry must evolve to meet modern environmental standards, or it will become obsolete.