对于系统，翻版的模拟是在控制图中添加一个创建循环的边，而不仅仅是一个附加节点。

In business, as in life, integrity is the only currency that never loses value.

Good research is like a good story—it has a beginning, a middle, and an end, and it holds together logically.

Life is about timing. The right thing at the wrong time is the wrong thing.

过去并不属于我们，而我们属于过去。

We are all alone in this world, and we must find our own way.

相关性和因果关系之间的区别在实证工作中是根本性的。