They wanted to understand this phenomenon that "here you have a class, that's larger than Introduction to Economics".

他们对这一奇特现象非常好奇，“竟然有比经济学导论更热门的课程。

哈佛公开课 - 幸福课课程节选

You see they had to explain to themselves as well as the audience, ?" "how come this lecture is larger than the Introduction to Economics?"

因为他们要说服自己，说服观众，“这门课怎么会比经济学导论跟热门“

哈佛公开课 - 幸福课课程节选