By that time, I had Saved a pretty big amount of money for those days.

到那时为止,我已为下个时期积攒下了大笔的积蓄。

耶鲁公开课 - 金融市场课程节选

it was reversible, so you can give people money and take it away, and you could actually scale the amount of money, so it makes a very handy experimental tool.

这个过程是可逆的，这样你可以给人钱，然后拿走，而且你还可以积攒钱，这就让钱成为了一种非常有用的试验工具。

斯坦福公开课 - 7个颠覆你思想的演讲课程节选