When you write a new joke, there is an "a-ha" moment in your brain that says this will make people "ha-ha" when you share it with them later. But what if you’re not the first person to think of the joke? Uh-oh.

Some people argue that everything you could joke about already has been given a punchline — that’s why comedians may decide to only talk about what happens in their own lives (and even in doing so, they’re talking about universal truths) or become topical and talk about current events ripped from the headlines (in which case, they join an entire group of comedians and TV personalities and radio DJs doing the same thing). As this Reuters story about a joke book from the Fourth Century A.D. suggests: "Many of its 265 gags will seem strikingly familiar, suggesting that sex, dimwits, nagging wives and flatulence have raised laughs for centuries." The reporter goes on to compare an ancient Greek joke — about a man complaining after he buys a slave who dies — to the popular Monty Python dead parrot sketch. All for what turns out to be not an archaeological find, per se, but a sales pitch for a British company that has hired a comedian to read the jokes in a multimedia production, Philogelos: The Laugh Addict. Do you buy this story? Or, rather, would you buy this modern-day adaptation of 1,600-year-old jokes?