Can you imagine ? Harvard vs. Yale football without the law of gravity?

你能想象哈佛和耶鲁,在没有万有引力的情况下进行橄榄球赛吗？

哈佛公开课 - 幸福课课程节选

Can you imagine a basketball game without the law of gravity?

你能想象没有万有引力情况下的篮球赛吗？

哈佛公开课 - 幸福课课程节选

Things would be so much easier without the law of gravity.

如果没有万有引力，事情就易办多了。

哈佛公开课 - 幸福课课程节选