Catch-22 (logic)

Catch-22 is a situation where no matter what you do, you can’t win. It’s like if a game had a rule that said you couldn’t win. So, no matter what other rules the game had, you couldn’t follow them to win. Think of it kind of like a puzzle with two pieces that can never quite fit together.

It comes from a book and a movie called “Catch-22”, which is about the World War II. In the story, there is a law known as Catch-22. It basically says that any soldier who is too insane to fly can’t be discharged, but any soldier who keeps asking to be discharged must be sane enough to fly!
So no matter what, soldiers can’t get discharged--they’re stuck. That’s Catch-22 in a nutshell.