The Book of Soyga, the puzzle of letters that obsessed John Dee

Among the books owned by John Dee, mathematician, astrologer and adviser to Queen Elizabeth I, there was one that tormented him for years. He called it the Book of Soyga and regarded it as a source of hidden knowledge that he could not penetrate on his own. For centuries it was believed lost, until in 1994 the historian Deborah Harkness identified two copies in English libraries, kept under a different title.

Aldaraia sive Soyga vocor

The two copies are at the British Library in London, among the manuscripts of the Sloane collection, and at the Bodleian Library in Oxford. The title they bear is 'Aldaraia sive Soyga vocor', that is, 'I am called Aldaraia, or Soyga'. The Latin text gathers material on magic, astrology and demonology, together with long lists of angelic names, partly shared with other magical treatises of the late Middle Ages.

The most surprising part, however, is something else: thirty-six large tables, each made up of thirty-six rows and thirty-six columns of letters. At first sight they look like random sequences, without any recognisable word. Dee was convinced they contained a message of great importance and that understanding it required help beyond that of mere learning.

Dee, Kelley and the archangel

In 1583, during the sessions in which the seer Edward Kelley claimed to see and hear angels in a crystal stone, Dee asked about the book. According to his diaries, the archangel Uriel replied that the book had been revealed to Adam in the earthly paradise and that only the archangel Michael could interpret it. The answers reflect the beliefs of the two men and say nothing about the real origin of the text.

In the same years Dee and Kelley transcribed large tables of letters and a language they called angelic, now known as Enochian. The taste for alphabetical grids found in the Book of Soyga reappears in those papers, although the direct relationship between the two is debated. Nor is it established with certainty whether one of the two surviving copies is the very one Dee consulted.

The secret of the tables

In 1996 the American mathematician Jim Reeds, studying the rediscovered copies, identified the method by which the tables had been built. Each starts from a keyword and develops according to a fixed rule, in which every new letter depends on those around it. The tables therefore do not hide a message to be read: they are the product of a mechanical procedure, applied patiently and without errors.

The discovery does not diminish the book's interest; if anything it increases it. It shows that an author of the late Middle Ages or early Renaissance knew complex combinatorial techniques and used them to produce grids meant to appear full of meaning. It is valuable evidence of the bond between mathematics, cipher writing and magic in the Europe of that time, when calculation was also a tool of contemplation.

The Book of Soyga remains without an author and without a precise date. Its story, however, illustrates the way Dee read books: as doors to an original knowledge, to be opened with the help of angels rather than philologists. Today, thanks to philologists and mathematicians, we at least know how that door was built.