Write a second Voynich

The Voynichizer writes a second Voynich manuscript. Give it a text and a key: it composes a new book of 207 pages, named like the folios of the real one, with its vocabulary, word shapes, lines, paragraphs and sections: a Voynich II that aims to be indistinguishable from the original, and is measured against it (see the note at the bottom). Hidden in its word counts is your text: with the same key it comes back exactly; without it, there is nothing to read.

Your text

The limit is in bits, not characters: about 10,000 bytes once compressed, i.e. roughly 20,000 characters of ordinary prose, more if the text is repetitive, fewer in scripts that take more bytes per character.

Key

Use a long random passphrase, six random words or twelve random characters, and a different one for every book. Without it the text cannot be read back, and nobody can recover it for you.

The book The manuscript as EVA text (.txt), always: it is the file you need to read the text back. Also the illustrated book, as a PDF: your manuscript written on vellum in a Voynich-like script, around real drawings lifted from the Voynich (the folio’s own, or one from the same section when it has none). The drawings are not generated, and the text is running paragraphs only, with no labels or circular text.

More options

A book with no message (the text is ignored). Without the key it cannot be told apart from a book that carries one: a classifier trained to separate them scores AUC 0.506, that is, it guesses.

Everything happens in your browser: your text and your key never leave this computer. The first time, the page fetches about 27 MB (Python and its libraries); writing a book takes a few minutes.

How close the copy comes is measured, not claimed: two classifiers trained to tell its pages from the real ones score 0.55 and 0.60 over 24 keys, where 0.5 is a coin toss and 1 a perfect judge. See what it has in common with the Voynich and the measurements.

A plant with blue flowers, from the herbal section of the Voynich manuscript — Beinecke MS 408, f. 9v

Write a second Voynich

The manuscript is written