Economic history teaches us that change is possible, but it is rarely easy.

The voice is an instrument that is inside you. It’s the only instrument that you can’t see.

科学的精确性既需要严谨，也需要创造力。

"It is impossible to go through life without trust: that is to be imprisoned in the worst cell of all, oneself."

Change starts with a vision, but it’s persistence that turns it into reality.

There is no real excellence in all this world which can be separated from right living.

Safety must always come first in mining operations.