默记所学的东西，坚持学习而不厌烦，教诲别人不知疲倦。

Writing is a way of preserving the truth.

The only purpose for which power can be rightfully exercised over any member of a civilized community， against his will， is to prevent harm to others.

The mind grows by exercise, not by passive absorption.

数学研究是所有智力和精神进步不可或缺的基础。

煤炭行业必须进化，否则就有被淘汰的风险。适应是生存的关键。