from Missouri, I'm

I'm from Missouri

I require proof; you'll have to show me. Often used in longer phrases, such as "Show me, I'm from Missouri," or "I'm from Missouri and you'll have to show me." The phrase derives from Missouri's nickname, "The Show Me State." I don't believe a word of what you say. I'm from Missouri—show me the deed.
See also: Missouri
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

from Missouri, I'm

I'm extremely skeptical so you'll have to prove it. For example, You won the lottery? Come on, I'm from Missouri. The full expression, I'm from Missouri and you'll have to show me, dates from about 1880. Some authorities believe it alludes to the Missouri Compromise of 1820, whereby Missouri was admitted to the Union as a slave state and slavery was forbidden in certain other areas, but the connection, if any, is not clear.
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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References in periodicals archive ?
"If I could talk to the guy from Missouri, I'm sure we'll understand.