William Friedman was the finest codebreaker the United States ever had, the man whose team broke Japan's top secret cipher in the Second World War, reading Tokyo's cables before its own ambassadors did. One small medieval book defeated him for forty years.
The Voynich manuscript is six hundred years old, carbon-dated to the early 1400s, filled with looping text in an alphabet found nowhere else and drawings of plants that grow nowhere on Earth. Friedman ran study group after study group on it, in his off hours, certain a mind trained to break any cipher could force this one open. It never gave.
He died in 1969 without reading a line of it. But he left his single conclusion hidden, the way a codebreaker would, as an enciphered sentence tucked into a published paper. Decoded, it is an admission of defeat: he had come to believe the book was an early attempt to invent an artificial language, and that he could not prove even that.
ALT Cryptologist William F. Friedman at work in 1924, intent in profile.
ALT A page of the Voynich manuscript, covered in unknown looping script beside a drawing of an unidentifiable plant.