So my student called Bernard Sadow up and asked him about his invention and he said, "Yeah, I was thinking, why don't we have wheels on suitcases?

于是我的学生打电话给伯纳德？沙度,然后询问了他关于发明的事情，他说道，是啊，我当时在想，我们为什么不能在行李箱上安轮子呢？

耶鲁公开课 - 金融市场课程节选