Cicco Simonetta's cipher-breaking rules
Cicco Simonetta has been described as an important cryptanalyst (and perhaps the encipherer of the Voynich Manuscript) in consideration of his famous rules for solving medieval ciphers. His work is in reality a collection of hints for solving ciphers that were rather old-fashioned at that time. Examples of 15th century ciphers confirm that contemporary cipher clerks were well equipped to defy the tricks described by Simonetta.
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