What If? is the title of a terrific book on writing by Anne Bernays and Pamela Painter. The book contains plenty of worthwhile advice and prompts, but I love the title alone: What If? Those two words can be the start of numerous inspiring prompts. To give you a real-life example, consider the song “Taxi” by Harry Chapin, the song that launched his successful musical career.

As the story goes (according to Harry’s brother Tom), Harry met a woman named Clare in the summer of 1960, when they were in their late teens. A romance began, which Clare’s father, president of Eastern Air Lines, didn’t approve of. The romance lasted for some time, but then faded. Several years later, Harry got a hack license to drive a cab in New York City. His former girlfriend Clare always took cabs, never subways. And so, two days before he’s due to start his first twelve-hour shift, he starts wondering, “What if Clare gets in my cab?”

What if.

Although Harry never actually drove a cab (he ended up taking a different job), the seed for the song was well planted. He changed the old girlfriend’s name to Sue and the location from New York City to San Francisco, and the song “Taxi” became a huge hit a couple of years after his aborted taxicab gig.

So, what if you’re driving a cab and your old lover flags you down? Or the person beside you on a five-hour plane trip is an old college friend who knows an embarrassing secret about you? Or you attend a wedding and see the woman who broke up your parents’ marriage? Or, on a lighter note, you’re on the subway and ET gets on—and no one else seems to notice?

What if …