Are the 1430s the most likely date range for the Zodiac drawings?

[Mark Knowles]

Mark, you seem very excited about something, but God only knows what.
Just what are you trying to prove here? Because I'm all at sea.

Well, I tend to be more excited by historical cryptography of the time, but it is true I am quite interested in this topic.

So, if the question as to whether the Voynich dates from before 1430 or after 1430 or whether drawings were copied from Lauber or not doesn't matter to you then this thread is not for you.

I think the degree of similarity in the drawings that Koen and others have uncovered with those of the central Zodiac drawings is very interesting as, whilst I haven't researched them in detail myself, it seems hard to deny that there is a connection. At the time I thought this research appeared interesting, but my researches were focused elsewhere, so I left the topic without delving into it.

Recently Koen made the claim with respect to the Hartlieb theory that the Voynich must date from before 1430. This attracted my attention as it seemed at variance with my own theory which implies that at least some of the Voynich manuscript was written in the early 1430. I didn't and don't feel the evidence justified the pre-1430 claim. Now, Koen has since retracted this claim.

So I decided to look in more detail at Koen's arguments that he makes on his blog. I don't think his claims for tracing the source from which the central Zodiac images are based is convincing and I have and am endeavouring to point out the weaknesses in that argument. It seems far more reasonable to trace the source to the 1430s than much earlier and Koen disagrees.