For one thing, one theory is that babies hear other babies cry, because babies are so stupid they think they themselves are crying; if they're crying they must be in some sort of pain so they cry some more."

例如，有理论说婴儿听到别的婴儿哭，因为婴儿都笨得要命,他们以为是自己在哭;,他们会以为自己哭了，那一定是痛了,所以他们就哭得更厉害”

耶鲁公开课 - 心理学导论课程节选