This was a failure because people could not go near the tickle machine without convulsing in laughter.

这是一个失败的发明,因为人们还没靠近挠痒痒的机器,就已经被它的模样逗笑了

耶鲁公开课 - 心理学导论课程节选

If you are happy, and work on your happiness, you are contributing indirectly to other people's happiness, just like the baby who laughed last time-- made you laugh.

你快乐并努力争取快乐，就是间直接对他人的快乐作出贡献，就像上次大笑的婴儿，把你们逗笑。

哈佛公开课 - 幸福课课程节选