Banburismus

Banburismus was a cryptanalytic process developed by Alan Turing at Bletchley Park in England during the Second World War. It was used by Bletchley Park's Hut 8 to help break German Kriegsmarine (Naval) messages enciphered on Enigma machines. The process used sequential conditional probability to infer information about the likely settings of the Enigma machine. Although this method is is frequently stated to be an example of Bayesian inference, Donald Gilles has argued (), that the process is not really Bayesian, but rather Popperian. It gave rise to Turing's invention of the ban as a measure of the weight of evidence in favour of a hypothesis. This concept was later applied in Turingery and all the other methods used for breaking the Lorenz cipher.

The aim of Banburismus was to reduce the time required of the electromechanical Bombe machines by identifying the most likely right-hand and middle wheels of the Enigma. Banburismus was a development of the "clock method" invented by the Polish cryptanalyst Jerzy Różycki. Good (1993) p. 155

Hugh Alexander was regarded as the best of the...
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