AI Used to Decrypt Medieval Ciphers
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Researchers are using machine learning algorithms to decrypt historical pencil-and-paper ciphers.
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NobodySpecial • June 3, 2026 3:58 PM
O.Henry wrote a short story – Calloway’s Code – in the early 1900’s. A wonderful example of something that AI would probably come up with, but I wonder if it could decode it?
Briefly, a reporter evades censorship rules by sending the first part of a common phrase and leaving off the last part. Knowing the phrases would give you the real message. Knowing the statistically-likely ending to the phrase would give it too.
But would an AI calculate that “cast of” should end in “thousands”, or that “3 to 4 cast of people” really meant “3 to 4 thousand people”?
Statistics are wonderful tools, but context is key.
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