(24-02-2016, 09:18 AM)-Job- Wrote: You are not allowed to view links. Register or Login to view. (20-02-2016, 06:07 PM)Sam G Wrote: You are not allowed to view links. Register or Login to view.It's hard to see a sensible motive here. I guess you could argue that there doesn't necessarily have to be one, and that the creator of the VMS could have been foolish or insane (despite having apparently been one of the greatest cryptographers of all time). But when you combine the fact that the properties of the text itself are incompatible with any known type of cipher with the fact that many other subtle aspects of the VMS seem incompatible with a cryptological intention, it seems more reasonable to conclude that we're not looking at a ciphertext here. Especially since I don't see any convincing positive evidence for a ciphertext being presented.
You're mostly arguing for the general improbability of a cipher, in several cases using the logical fallacy of argument from incredulity.
I am not using argument from incredulity. Attempting to understand the motives of the VMS creator from the decisions that he made is not fallacious, and it would seem to me that considering how a document such as the VMS is intended to be used would be pretty important to understanding what it is and why/how it was made. Actually I think it's a fairly standard thing to do with any document or even any artifact. I also note that you did not actually address any of the points I made.
Quote:Most VM theories may be depicted as improbable. For example, what's the probability that the VM contains an unreadable natural language which exhibits no clear association with any other known language?
What I'm trying to do is figure out what the VMS is by looking at the evidence, rather than deciding what it is a priori. I obviously don't consider the idea that a medieval European document could be written in an otherwise unattested and presumably non-European language to be so unlikely as to rule it out a priori, but then I tend to assume that there's much about history that we don't know - you might feel differently.
This is the major problem with the theorizing around the VMS as far as I'm concerned - the tacit assumption that the VMS must be historically unimportant and must not contain anything fundamentally new or significant, which leads to the view that it cannot be an unencrypted natural language text no matter what the evidence suggests (because this would make the VMS historically important for a number of reasons), which then leads to all the unworkable cryptological theories that are in complete contradiction to the available evidence. I might write a separate post on this topic.
Quote:Your premise that low entropy is only compatible with a verbose cipher is false, AFAIK. For example, null characters can also lower the character entropy depending on how they're employed.
This could be considered a form of verbose cipher, and you'd still have the same problem: short word lengths.
I think lossy substitution ciphers (where you map multiple plaintext letters to the same ciphertext letter) can also lower entropy - if I'm not mistaken, Jim Gillogly points that out as the only other entropy-lowering cipher he could come up with somewhere in the list archives. But again, it can be ruled out in the case of the VMS, at least for European languages.
Quote:Also, relating the VM's low character entropy with Japanese or Hawaiian without accounting for its other properties is comparable to classifying the VM as a verbose cipher without accounting for the word lengths.
Doesn't really matter as far as refuting the cipher theory is concerned. If there's some reason to think that a natural language with low entropy could not possibly possess some property found in the VMS text, it would not really help the cipher theory, but only undermine the natural language theory, and support the gibberish theory - but I don't see that there is any such reason.
Quote:Is there a language or cipher that matches all of Voynichese's features? I think that should be the focus of this discussion.
Not a known language or a known cipher, of course - that seems pretty clear, though I guess there are still plenty of languages in the world that haven't been checked. In theory it could be mostly the same as a language that's still in use by a small population, though I doubt this. So the question is really whether it's an unknown language, or a cipher mechanism that remains unknown and undemonstrated as of 2016, or a form of gibberish produced by a mechanism that remains unknown and undemonstrated as of 2016.