Language is the key to understanding higher mental processes.

Sustainability isn't a trend—it's our responsibility to the craftsmen, the forests, and the next generation.

自然是最难维持的姿态。

The greatest prosperity can exist only as the result of the greatest possible productivity of the men and machines of the establishment.

You can't control what you don't measure.

学习数学的唯一方法就是做数学。