It’s a nice historical detective story, one kicked off by John Dee, Frances Yates‘ favourite Elizabethan ‘magus’ (though I personally suspect Dee’s ‘magic’ was probably less ‘magickal’ than it might appear), when he claimed to have told an angel that his “great and long desyre hath byn to be hable to read those tables of Soyga“. Dee lost his precious copy of the “Book of Soyga” (but then managed to find it again): when subsequently Elias Ashmole owned it, he noted that its incipit (starting words) was “Aldaraia sive Soyga vocor…“.

However, since Ashmole’s day it was thought to have joined the serried, densely-stacked ranks of long-disappeared books and manuscripts, in the “blue-tinted gloom” of some mythical, subterranean library not unlike the “Cemetery of Lost Books” in Carlos Ruiz Zafon’s novel “The Shadow of the Wind” (2004)…

Fast-forward 400 years to 1994, and what do you know? Just like rush hour buses, two copies of the “Book of Soyga” turn up at once, both found by Deborah Harkness. Rather than searching for “Soyga“, she searched for its “Aldaraia…” incipit: which is, of course, what you were supposed to do (in the bad old days before the Internet).

It is a strange, transitional document, neither properly medieval (the text has few references to authority) nor properly Renaissance. There are some mysterious books referenced, such as the Liber Sipal and the Liber Munob: readers of my book “The Curse of the Voynich” may recognize these as simple back-to-front anagrams (Sipal = Lapis [stone], Munob = Bonum [Good], Retap Retson = Pater Noster [our Father]). In fact, Soyga itself is Agyos [saint] backwards.

But what was the secret hidden behind the 36 mysterious “tables of Soyga” that had vexed John Dee so? 36×36 square grids filled with oddly patterned letters, they look like some kind of unknown cryptographic structure. Might they hold a big secret, or might they (like many of Trithemius’ concealed texts) just be nonsense, a succession of quick brown foxes endlessly jumping over lazy dogs?

  • oyoyoyoyoyoyoyoyoyoyoyoyoyoyoyoyoyoy
    rkfaqtyoyoyoyoyoyoyoyoyoyoyoyoyoyoyo
    rxxqnkoyoyoyoyoyoyoyoyoyoyoyoyoyoyoy
    azzsxbqtyoyoyoyoyoyoyoyoyoyoyoyoyoyo
    sheimasddtguoyoyoyoyoyoyoyoyoyoyoyoy
    eyuaoiismspkfaqtyoyoyoyoyoyoyoyoyoyo
    enlxflfudzrxxqnkoyoyoyoyoyoyoyoyoyoy
    sxcahqczfbtfzsxbqtyoyoyoyoyoyoyoyoyo
    azepxhheurgmyknqnkoyoyoyoyoyoyoyoyoy
    rlbriyzycuyddpotxbqtyoyoyoyoyoyoyoyo
    ryrezabirhdiszeknqnkoyoyoyoyoyoyoyoy
    ogzgfceztqalpntsxhssyoyoyoyoyoyoyoyo
    opnxxsnodxqhuekknykkoyoyoyoyoyoyoyoy
    rcqsfueesfsqrqgqrossyoyoyoyoyoyoyoyo
    roauxmdkkxkhyhmpzqphdtgtguoyoyoyoyoy
    aqxmudiamubkoqifbszktdmspkfaqtyoyoyo
    sazoesrmlrnaqnzhgabmsmlpeahfsddtguoy
    ………………………………
    (etc)

Jim Reeds, one of the great historical code-breakers of modern times, stepped forward unto the breach to see what he could make of these strange tables: he transcribed them, ran a few tests, and (thank heavens) worked out the three-stage algorithm with which they were generated.

Stage 1: fill in the 36-high left-hand column (which I’ve highlighted in blue above) with a six-letter codeword (such as ‘orrase‘ for table #5, ‘Leo’) followed by its reverse anagram (‘esarro‘), and then repeat them both two more times

Stage 2: fill each of the 35 remaining elements in the top line in turn with ((W + f(W)) modulo 23), where W = the element to the West, ie the preceding element. The basic letter numbering is straightforward (a = 1, b = 2, c = 3, … u = 20, x = 21, y = 22, and z = 23), but the funny f(W) function is a bit arbitrary and strange:-

  • x f(x) x f(x) x f(x) x f(x)
    a…2, g…6, n..14, t…8
    b…2, h…5, o…8, u..15
    c…3, i..14, p..13, x..15
    d…5, k..15, q..20, y..15
    e..14, l..20, r..11, z…2
    f…2, m..22, s…8

Stage 3: fill each row in turn with ((N + f(W)) modulo 23), where N = the element to the North, ie the element above the current element.

For example, if you try Stage 2 out on ‘o’, (W + f(W)) modulo 23 = (14 + 8) modulo 23 = 22 = ‘y’, while (22 + 15) modulo 23 = 14 = ‘o’, which is why you get all the “yoyo”s in the table above.

And there (bar the inevitable miscalculations of something so darn fiddly, as well as all the inevitable scribal copying mistakes) you have it: the information in the Soyga tables is no more than the repeated left-hand column keyword, plus a rather wonky algorithm.

You can read Jim Reeds paper here: a full version (with diagrams) appeared in the pricy (but interesting) book John Dee: Interdisciplinary essays in English Renaissance Thought (2006). The End.

Except… where exactly did that funny f(x) table come from? Was that just, errrm, magicked out of the air? Jim Reeds never comments, never remarks, never speculates: effectively, he just says ‘here it is, this is how it is‘. But perhaps this f(x) sequence is in itself some kind of monoalphabetic or offseting cipher to hide the originator’s name: Jim is bound to have thought of this, so let’s look at it ourselves:-

  • 1.2.3.4..5.6.7.8..9.10.11.12.13.14.15.16.17.18.19.20.21.22.23
    2.2.3.5.14.2.6.5.14.15.20.22.14..8.13.20.11..8..8.15.15.15..2

If we discount the “2 2” at the start and the “8 8 15 15 15 2” at the end as probable padding, we can see that “14” appears three times, and “5 14” twice. Hmm: might “14” be a vowel?

  • 2 3 5 14 2 6 5 14 15 20 22 14 8 13 20 11 8
  • a b d n a e d n o t x n g m t k g
  • b c e o b f e o p u y o h n u l h
  • c d f p c g f p q x z p i o x m i
  • d e g q d h g q r y a q k p y n k
  • e f h r e i h r s z b r l q z o l
  • f g i s f k i s t a c s m r a p m
  • g h k t g l k t u b d t n s b q n
  • h i l u h m l u x c e u o t c r o
  • i k m x i n m x y d f x p u d s p
  • k l n y k o n y z e g y q x e t q
  • l m o z l p o z a f h z r y f u r
  • m n p a m q p a b g i a s z g x s
  • n o q b n r q b c h k b t a h y t
  • o p r c o s r c d i l c u b i z u
  • p q s d p t s d e k m d x c k a x
  • q r t e q u t e f l n e y d l b y
  • r s u f r x u f g m o f z e m c z
  • s t x g s y x g h n p g a f n d a
  • t u y h t z y h i o q h b g o e b
  • u x z i u a z i k p r i c h p f c
  • x y a k x b a k l q s k d i q g d
  • y z b l y c b l m r t l e k r h e
  • z a c m z d c m n s u m f l s i f

Nope, sorry: the only word-like entities here are “tondean”, “catsik”, and “zikprich”, none of which look particularly promising. This looks like a dead end… unless you happen to know better? 😉

A final note. Jim remarks that one of the manuscripts has apparently been proofread, with “f[letter]” marks (ie fa, fb, fc, etc); and surmises that the “f” stands for “falso” (meaning false), with the second letter the suggested correction. What is interesting (and may not have been noted before) is that in the Voynich Manuscript, there’s a piece of marginalia that follows this same pattern. On f2v, just above the second paragraph (which starts “kchor…”) there’s a “fa” note in a darker ink. Was this a proof-reading mark by the original author (it’s in a different ink, so this is perhaps unlikely): or possibly a comment by a later code-breaker that the word / paragraph somehow seems “falso” or inconsistent? “kchor” appears quite a few times (20 or so), so both attempted explanations seem a bit odd. Something to think about, anyway…

Sorry for posting like an overexcited puppy, but my Voynich book‘s first citation is surely worthy to me of a minor celebration: less than a backflip, but more than a raised eyebrow.

The just-published (January 2008) Cryptologia article where it is mentioned is “Cicco Simonetta’s Cipher-Breaking Rules“, by Augusto Buonafalce, who so generously reviewed my book in the same journal last year. It’s a nice little piece to introduce cryptologers and cryptography historians to Cicco Simonetta [there’s a nice Italian page on him here], with the added bonus of a good translation of his “regulae” (rules): it even has a black and white reproduction of a painting of Cicco I was not previously aware of.

Augusto rightly dismisses the thought of a powerful Milanese statesman “engaging in the encryption of the Voynich manuscript“: but that’s not really a summary of my book’s argument. What I actually argue is that the presence of the “4o” token in a good number of mid-Quattrocento Northern Italian cipher alphabets (including the Voynich Manuscript) points to a continuity of cipher thinking, one which seemed to travel around with the Sforza miltary caravan… just as Cicco Simonetta did from an early age.

To be precise, I don’t claim that Cicco wrote the VMs, or even designed its cipher alphabet. Far from it: rather, that its “4o” token points to a deep-rooted connection between its cipher-system and the ciphers constructed and used by the Milanese Chancellery. My book conjectures that this “4o” ‘verbose cipher’ trick may have been disclosed in the 1465 meeting between Antonio Averlino and Cicco Simonetta, at which the former placed his outstanding Milanese affairs in the hands of the latter before leaving Milan forever. But in the world of tenuous Voynichological hypotheses, this is one at least that did actually happen! 🙂

For all its merits, it would be wrong to characterize Augusto’s Cryptologia article as being the final word in the cryptographic history debate over Cicco Simonetta’s Regulae: the conclusions I (and others) draw from the available data are quite different, and (in the absence of more conclusive evidence) we can politely agree to differ – and that’s OK.

As a side-note here, when I cited (on my p.182) a 1970 article on Cicco’s Regulae, I contacted its very-much-still-alive author (Walter Hoeflechner) to see if anyone else in the intervening 36 years had shown an interest – and only the ubiquitous David Kahn had. From that, it’s easy to see that the discussion of the intriguing intersection between cryptography and politics offered by Simonetta is very much out of fashion: which is a bit of a shame.

And therefore, I think it would be very nice if Augusto’s article proved instead to be the first word in a rather more modern debate over the Regulae: the new generation of historians and researchers who have taken an interest in seeing what the Sforza-era bureaucratic archives have to tell us would almost certainly be bound to find new angles and approaches, and might well carry us all forward in new and interesting directions.

Finally… for me, what is nicest about Augusto’s citation is that it is one of those rarest of hen’s teeth: a Voynich-related book or paper getting cited outside of the Voynich literature. It is far too early to say that this marks the point where the VMs goes fully mainstream… but it’s a start, surely?