Nature and history are the two great sources of geographical knowledge.
自然和历史是地理知识的两个重要来源。
法律不是规则的体系,而是原则的体系。
We need to be obsessed with our customers' unmet, unarticulated needs.
预言未来最好的方法是回顾过去
Mathematics is the art of giving the same name to different things.