What type of different foods were they eating, and how much effort went into getting them?

他们吃着什么样不同的食物呢,他们为此付出多大的努力

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

Externality When I'm figuring out how much effort to contribute to this firm I don't take into account that other half of profits that goes to you.

外部性,当我计算要为公司付出多少时,我没考虑到利润的一半会归你所有

耶鲁公开课 - 博弈论课程节选