What is the origin of the idiom Catch 22?

Hello everybody. Your forum is good and I’m sure somebody will be able to tell me the origin of the term catch 22? I understand this describes a very tricky situation with no sign of a solution by why is it 22 and not 23?

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The phrase is taken from the book, the title of which is the same: Catch-22, by Joseph Heller.

Heller coined the phrase to indicate a fictional military regulation which is a cyclical conundrum, or no-win situation.
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I’m not allowed to write here as a student because teachers can answer only. I suppose that the 22 is the diameter of a barrel of a gun. I sometimes meet an abbreviation .22. And I think this is it. If I’m wrong, correct me please.

Best regards,
Simon

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You are certainly welcome to respond here, Simon. You are right that .22 is a caliber, a measurement of the diameter of a gun barrel-- but it is a very small caliber, not used in military weaponry, so it is inappropriate for this anti-war novel.

I don’t think that Heller had any particular meaning in mind-- I think he just chose an arbitrary number. Here is a quote from Wikipedia:

A magazine excerpt from the novel was originally published as “Catch-18,” but Heller changed the title after another World War II novel, Leon Uris’s “Mila 18”, was published.
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