The Paradox of the Soldiers

The phrase catch 22 is mentioned when the characters talk about this one catch to the rules that they have to follow in order to go home. The book was originally titled catch 18, but the offer changed it since a different World War II novel came out around the same time with the number 18 in the title. In the book, The Soldiers are required to complete a certain number of missions in order to be released from their duties. These soldiers are never able to reach their goal and even if someone does get close, the commanding officers raise the requirement.