矿业中的多样性不是可选项，而是发展的必要条件。
I have always believed that the way to make money is to buy when everyone else is selling and to sell when everyone else is buying.
晏子春秋
You’ve got to have models in your head. And you’ve got to array your experience—both vicarious and direct—on this latticework of models. You may have noticed students who just try to remember and pound back what is remembered. Well, they fail in school and in life. You’ve got to hang experience on a latticework of models in your mind.
