Having examined many historical ciphers over the last few years, I’d say that there are only a handful of ways in which individal ‘cipherbets’ (i.e. “cipher alphabets”) are typically constructed. The big fallacy is to think that people building ciphers are only concerned with a need for long-term message security, when actually there are plenty of other important short term needs they have to attend to, such as: ease of construction, usability, speed of deciphering, aide-memoires, etc. Broadly speaking, these needs express themselves in the following aspects of the cipher alphabet:-
- Symmetrical – where the letter-shapes are based around a geometric / symmetrical pattern
- Incremental – where the cipher alphabet is adapted from a pre-existing cipher
- Practical – where the letter-shapes are optimized for speed of writing
- Stylistic – to give an overall effect of looking exotic / strange / occult / ancient
- Mnemonic – where letter-shapes contain associative reminders about the plaintext letter
- Steganographic – where letter-shapes hide visual hints as to the plaintext shape
- Deceptive – where letter-shapes vary in subtle ways to hinder transcription / decipherment
- Distracting – where letter-shapes are constructed to resemble a different type of text
Apart from ‘pure’ symmetrical ciphers (such as the various pigpen and Masonic ciphers, or indeed Edward Elgar’s Dorabella cipher alphabet),I would say that most cipher alphabets tend to present a blend of only two or three of these, which you can sensibly read as reflecting the most pressing needs of the encipherer. As brief examples, you might note that many of the Sforza ciphers were primarily [incremental + practical] (and occasionally stylistic, such as the 1464 cipher for Tristano Sforza), while I’d predict that Cod. Pal. Germ. 597 will turn out to be [mnemonic + stylistic].
What, then, of the Voynich Manuscript’s cipher alphabet? Of course, the hope is that if we can classify its cipher alphabet, we might be able to “read” the needs of its encipherer.
The first thing to note is Steve Ekwall’s extraordinarily specific claim about the four gallows shapes: he asserts that these four shapes (and their four ‘ch’ strikethrough versions) specifically depict the eight folding states of the deciphering paper key – basically, that these are mnemonic. While that would make a lot of sense, debating that in sufficient detail is something I’ll take on another time.
Regardless, my position on the Voynich Manuscript’s alphabet is simply that it is a tour de force of cipher construction technique, insofar as I think you can see traces of symmetrical, incremental, practical, stylistic, steganographic, deceptive and distracting aspects (which, curiously enough, would make Ekwall’s mnemonic the only one missing from the list). Here they are in more detail:-
The four gallows shapes exhibit an explicit structural symmetry – one leg or two legs, one loop or two loops.
The four strikethrough gallows look to have been developed from an earlier (probably less secure) cipher system based purely on the four simple gallows. I also suspect that the “e / ee / eee / ch / sh” letter-shapes represent vowels, and that they were in some way incrementally adapted from a variation of the “dots for vowels” ciphers used by some medieval monks.
The Voynich Manuscript’s letter-shapes have been consciously constructed for ease and speed of writing, far more so than typical cipher alphabets of the time.
I would argue that the overall form of the alphabet has been designed with older (non-cipher) alphabets in mind – that is, that the stylistics of the letter-shapes was deliberately chosen to resemble an archaic (but lost) alphabet. Note (mainly for Elmar Vogt): I do not therefore believe that the Voynich Manuscript was meant to resemble an enciphered medieval herbal, but rather that it was meant to ressmble an unenciphered herbal written in an archaic (but lost) language. I fail to see how this makes it unlikely to be smuggled past Venetian border guards… but that’s an argument for another day!
As I argued in The Curse and elsewhere on this blog, I am convinced beyond any doubt that the “aiir” and “aiiv” cipher letter groups in the VMs are specifically meant to resemble medieval page references (i.e. “a ii v” denotes “[quire] a, [folio] ii, v[erso]”), but that this is meant to distract contemporary eyes from looking in detail beyond that.
I believe that the actual Arabic numbers enciphered by the “aiiv” family are to be read from the shape and position of the final flourish of the “v” – and that whereas the (earlier) Currier A pages used a system based on the position of the flourish, the (later) Currier B pages used a system based on the shape of the flourish. This would also point to incremental cipherbet change during the overall writing process!
There is one further one to discuss – steganographic. If you stare at the Voynich Manuscript’s cipher alphabet long enough, I contend that you will (eventually) grasp the logic underlying most of the letter-shapes (as per the discussion above). However, you are still left with a few odd “spares” (such as “4o”, “8” and “9”) that don’t fit into the symmetric families and groups described above. What is going on with them?
In The Curse, I argued (based on the statistics) that “4o” was probably encoding a word-initial abbreviation sign: what I now think is fascinating is the notion that the letter shape for the “4” might also be steganographically hiding a horizontal stroke, as an aide-memoire to the decipherer.
Similarly, I argued (also based on the statistics) that the “8” shape and the “9” shapes were probably encoding word-middle and word-final abbreviation signs (respectively): similarly, I think that these are steganographically hiding a curved half-loop at the top of each of them, the typical mid-Quattrocento sign denoting contraction and abbreviation. I’ve marked these hidden strokes in red below:-
Actually, I suspect the author might possibly have given a little bit of the game away on page f2r, via a slip of the pen: para 2 line 3 word 1 is “4oP9” with a curved contraction half-loop added over the “o”, which I think might well denote a contraction of “4o” + “oP” + “9”. But that, too, is another story. 🙂
All in all, I’d say that if the Voynich Manuscript’s cipher system turns out to have broadly the same degree of subtlety and roundedness exhibited by its cipher alphabet, then no wonder it has remained unbroken for centuries. It has not only the Everest of cipher systems, but also the Rolls Royce of cipher alphabets!