The purpose of a model is to be simple enough to understand and use, but complex enough to capture the essential features of the system.
模型的目的是足够简单以便理解和使用，但又足够复杂以捕捉系统的基本特征。
The biggest risk is not taking any risk. In a world that's changing quickly, the only strategy that is guaranteed to fail is not taking risks.
我不相信后悔。一切都有原因。
创新是成功的关键。
Every new day is another chance to change your life.
领导的艺术在于说不，而不是说是。说是很容易的。
债券市场是市场心理的最终衡量标准。