AUDIE CORNISH, HOST:
The cryptic text of a 250-year-old secret society has finally been translated. Researchers from North America and Europe used a powerful computer program to break the code. Daniel Hajek reports on how they did it.
DANIEL HAJEK, BYLINE: University of Southern California computer scientist Kevin Knight is leafing through a Xeroxed copy of the Copiale Cipher, a 105-page document written entirely in code.
KEVIN KNIGHT: On this page we see a capital N, Z, three, a Greek letter, lambda...
HAJEK: Earlier this year, Knight and two colleagues from the University of Uppsala in Sweden acquired copies of the mysterious cipher. Their first step was to use automatic language translation software to compare the secret text to 80 European languages.
KNIGHT: In this case, it gave a very slight preference for German, which helped us focus.
HAJEK: The preference, because the text was found in Berlin. The computer then matched patterns of symbols to patterns found in the German language.
KNIGHT: Then we just collaborated from there, working with the manuscript, deciphering the manuscript, using different language expertise.
HAJEK: And four months later, they had the entire thing figured out. One of the Swedish researchers, Dr. Beata Megyesi says that by combining simple ideas and modern technology...
DR. BEATA MEGYESI: You can actually succeed to break a code in a very short period of time.
HAJEK: She explains that they had to translate 90 different letters that make up the 75,000 characters in the coded text.
MEGYESI: These are used to encrypt a great majority of the book, and there are 11 logograms.
HAJEK: Logograms are symbols that represent words - symbols like an eye, which signifies their society. Back in Knight's office, we look at a chart of translations he's drawn in one of his notebooks.
KNIGHT: Across the top of the page are the German letters, and down the left side of the page are the cipher letters.
HAJEK: For example, vowels with dots above them represent the letter e and the symbol of a cross stands for, S-C-H. Their complete translation of the cipher uncovered the 18th century secret society, which stood for...
DR. CHRISTIANE SCHAEFER: Rather radical political ideas about freedom, equality of human beings and also ideas about the right to kill a tyrant.
HAJEK: That's Dr. Christiane Schaefer, the third researcher who worked on this project.
SCHAEFER: I had started suspecting that the secret society behind this was the Oculist society dealing with eye medicine.
HAJEK: One of the biggest clues pointing to a group called, the Oculist Society, is this description of an eye procedure, found in the passage about member initiation.
UNIDENTIFIED MAN: (Through Translator) All those present members reach for the candles and place themselves around the candidate and the master of ceremonies. He plucks a hair from the eyebrow with a pair of small tweezers, and concludes herewith the operation.
HAJEK: The details of that operation aren't in the Copiale Cipher, and no amount of cryptography can uncover the exact proceedings of their mysterious ceremonies. So, the best kept secrets of the Oculist Society may never be known. For NPR News, I'm Daniel Hajek.
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