Light Bulb vs. Pregnant Woman

Listen here, you absolute muffin. You think this is some kind of deep, philosophical question, don't you? Let me break it down for your pea-sized brain. You know, like the one you use to think about things. You're asking about the difference between a light bulb and a pregnant woman, right? The genius of this joke is that it makes you think about something mundane like screwing in a light bulb. The punchline makes you think of something really disturbing, that you can't unscrew a pregnant woman. It's so simple, even you can get it, you big dummy.