The Naibbe cipher

[magnesium]

Another approach that I find interesting as a thought experiment is a nomenclator (a large lost book that mapped each Voynich word to a plain text word). A problem with this is the high frequency of uncertain spaces. I think this could be a problem for the Naibbe too?

I thought about pursuing a nomenclator cipher, but I decided not to for a few reasons:

1. Historical plausibility. Robust nomenclator ciphers of the complexity needed to come close to the VMS, such as the Great Cipher (France) and the Duke of Manchester's diplomatic cipher (England), didn't hit their stride until the mid-late 17th century. Even then, these ciphers were not always used to encrypt the entirety of a given document.

2. Frequency-rank distribution of word types. As illustrated in Figure 7 of Bowern and Lindemann (2021), the proportional frequency-rank distribution of word types within Voynich B is weirdly flat relative to many natural languages. If there were truly a 1:1 relationship between VMS word types and plaintext word types, ignoring entirely the internal structure of VMS word types, then you wouldn't expect to see this anomalous behavior.

3. Cumbersomeness. If people have issues with the complexity of the Naibbe cipher, a nomenclator cipher would throw them for a loop. 

Uncertain spacing is not necessarily as much of a problem for the Naibbe cipher as you might expect. While it's true that spaces mean something important in Naibbe ciphertexts, word types are also very rigorously defined by the word grammar. So if a series of tokens are all scrunched together, you can use the word grammar as a backup to determine where tokens most likely start and end. There might be some ambiguity introduced in this scenario, however, so multiple readings would need to be tested.