A Possible Reading of "rapa (turnip)" on f102v2

[rikforto]

On what basis do you assert that it is not simple substitution cipher?

This analysis is well known enough you can expect people to assert it without pointing to any of the many statements of it. You are not allowed to view links. Register or Login to view., but you will have to read the whole thing to get the details of the argument. Basically, though, words in the have letters in a restricted order, so simple substitution will only produce words with letters in a that restricted order. To be concrete, words cannot start with "n" if you assign "n" to n. You would need hundreds of pages of text without a word that follow the restrictions implied by the Voynich letter order, and that rules out a great many languages