A Glyph Is Not a Letter, a Token Is Not a Word, a Space Is Not a Space: What the Units of Voynichese Are Not
Organizations: International Institute for Applied Systems Analysis (IIASA), Laxenburg, Austria · University of Geneva, Geneva, Switzerland
Abstract
The Voynich manuscript (Beinecke MS 408) is usually analysed on three unstated assumptions: that its glyphs are letters, that the strings between blanks are words, and that every blank is a word space. We test all three against the Zandbergen-Landini transliteration with matched prose, cipher, and pseudo-text controls and quire-level resampling. None holds, and the failures share a shape: the order in Voynichese sits at the edges of tokens and at graded boundaries between them, not in the succession of tokens themselves. Glyph regularity is too strong for one-to-one substitution of any tested plaintext (conditional entropy 2.7 bits against about 3.5 for Latin, Italian, and English) and resolves instead onto a quire-stable scale of recurrent multi-symbol units. Tokens form a plausible vocabulary, yet the identity of one token predicts the next by under 1% of token entropy, below every matched control (2-10%), while the glyphs at token edges share 0.2 bits of mutual information, more than in any prose control. Blanks fall into two regimes: the separators transcribers marked uncertain behave like word-internal junctures, are physically narrower on the page (AUC 0.905 from independent image coordinates, with the same sign in a small blind ink audit), and are crossed by learned units even when every space is erased before learning. This profile is also what discriminates. A published Voynich-imitating cipher and a self-citation text generator both reproduce the low entropy, the unit scale, the weak token order, and the null result of a calibrated substitution attack; neither reproduces the edge-glyph coupling or the open, hapax-rich vocabulary (70% singleton types against 41% and 59-60%). Any account of the manuscript must therefore earn, rather than assume, the step from glyphs, tokens, and separators to letters, words, and word spaces, and these are the measurements on which to do so.
Figures & tables
| Assumed equivalence | Main tests | Warranted interpretation |
|---|---|---|
| EVA glyph = plaintext letter | Conditional-entropy invariance; BPE scale; calibrated cipher attack | Fixed one-to-one letter mapping is rejected for the tested sources; recurrent multi-symbol units are the supported analytical scale. |
| ZL token = lexical word | Static vocabulary; shuffle-corrected token and edge-glyph order; uncertain-space merging | The forms look lexical in isolation but their identities do not carry the adjacent ordering expected of tested prose or catalogue words; the order that exists sits at the token edges. |
| Separator = uniform word boundary | Boundary association; image gaps; space-erased BPE | Blanks are non-random but form at least two graded boundary regimes; lexical status is not established. |
| Representation | Size in the main analysis | Uses |
|---|---|---|
| Composite-collapsed EVA | 141,310 symbols; 47 observed types (25 frequent) | Boundary association, coordinate alignment, and the primary entropy comparison |
| Decomposed EVA | 173,572 entropy symbols; 173,076 BPE symbols | Representation sensitivity and data-driven unit learning |
| ZL surface tokens | 32,747 blank-delimited forms | Static vocabulary and adjacent-token order |
| Corpus | Types | Singleton types | Top-50 coverage | Excess bits | Order share |
|---|---|---|---|---|---|
| Voynich, observed spaces | 7,022 | 69.7% | 33.2% | 0.0661 | 0.79% |
| Voynich, weak spaces merged | 7,920 | 73.0% | 30.0% | 0.0438 | 0.54% |
| Latin narrative | 8,084 | 59.3% | 26.7% | 0.3256 | 4.00% |
| English narrative | 4,248 | 51.7% | 50.3% | 0.7422 | 9.18% |
| French narrative | 5,828 | 58.5% | 44.5% | 0.7828 | 9.72% |
| German narrative | 6,920 | 63.4% | 39.0% | 0.3866 | 4.81% |
| Last glyph first glyph | Token token | Edit-1 | |||
| Corpus | bits | share | bits | share | ratio |
| Voynich, observed spaces | 0.197 | 5.7% | 0.067 | 0.81% | 1.12 |
| Voynich, weak spaces merged | 0.162 | 4.8% | 0.044 | 0.54% | 1.14 |
| Voynich, Currier A | 0.137 | 3.9% | 1.20 | ||
| Voynich, Currier B | 0.248 | 7.4% | 0.029 | 0.35% | 1.07 |
| Latin botanical (lowest prose) | 0.018 | 0.4% | 0.148 | 2.03% | 0.56 |
| Boundary class | 95% quire-bootstrap interval | ||
|---|---|---|---|
| Within-token pair | 1.000 | anchor | – |
| Uncertain separator , | 0.494 | [0.464, 0.524] | 2,409 |
| First separator of line | 0.099 | [0.052, 0.145] | 3,834 |
| Mid-line separator | 0.064 | [0.002, 0.146] | 21,836 |
| Certain separator . | 0.029 | [-0.032, 0.111] | 27,073 |
| Continuation line break | -0.036 | [-0.072, -0.002] | 3,634 |
| Corpus | |||
|---|---|---|---|
| Voynichese, composite-collapsed EVA | 3.98 | 2.69 | 6.45 |
| Voynichese, decomposed EVA | 3.89 | 2.32 | 4.98 |
| Pliny, botanical Latin | 4.01 | 3.51 | 11.39 |
| Celsus and Caesar, Latin | 3.99 | 3.47 | 11.10 |
| Culpeper, English herbal | 4.16 | 3.52 | 11.50 |
| Italian prose | 4.01 | 3.45 | 10.91 |
| Stream | Order | Hapax | Edge | Edit-1 | Differential | Crossing | ||
|---|---|---|---|---|---|---|---|---|
| Voynichese | 2.69 | 1.05 | 0.79% | 70% | 0.197 | 1.12 | to | 2.5% |
| Naibbe cipher of Latin (Caesar) | 2.71 | 1.03 | 1.25% | 41% | 0.006 | 0.82 | 2.2% | |
| Naibbe cipher of Latin (Pliny) | 2.71 | 1.04 | 1.06% | 42% | – | – | 1.9% | |
| Self-citation generator (3 seeds) | 2.6–2.7 | 0.65–0.86 | 0.5–0.6% | 59–60% | 0.006–0.009 | 1.06–1.23 | to | – |
| Latin narrative | 3.44 | 1.24 | 4.00% | 59% | 0.033 | 0.43 | (index 0.99) | 15.5% |
| Synthetic homophonic ciphers | – | 0.8–1.1 | – | – | – | – | to | 3.8–12.4% |
| Hidden position class | Crossed | Total | Crossing rate |
|---|---|---|---|
| Voynich certain separator | 661 | 26,447 | 2.5% |
| Voynich uncertain separator | 477 | 2,350 | 20.3% |
| Voynich all intra-line positions | 97,402 | 162,330 | 60.0% |
| Latin word separator | 3,796 | 24,464 | 15.5% |
| Deterministic verbose-2 word separator | 1,528 | 12,360 | 12.4% |
| Homophonic verbose word separator | 464 | 12,360 | 3.8% |
Appendix figures & tables6 assets
Supplementary material from the paper’s appendix.
Appendix
| Configuration | Right language | Wrong language |
|---|---|---|
| H2 (two homophones) | [ , ] | [ , ] |
| H3 (three homophones) | [ , ] | [ , ] |
| H5 (five homophones) | [ , ] | [ , ] |
| H3mix (one-to-three groups) | [ , ] | [ , ] |
| H3rot (rotating tables) | [ , ] | [ , ] |
| Voynichese (14 comparisons) | [ , ] | |
| (56 types) | (88 types) | , compound (63) | ||||
|---|---|---|---|---|---|---|
| Category | types | occ. | types | occ. | types | occ. |
| Single decomposed EVA letter (unmerged) | 44.6 | 38.9 | 28.4 | 27.5 | 0.0 | 0.0 |
| (i) one Zattera slot character | 37.5 | 48.5 | 23.9 | 34.7 | 7.9 | 11.2 |
| (ii) two slot characters, increasing slots | 25.0 | 32.7 | 30.7 | 36.3 | 42.9 | 50.1 |
| of which in adjacent slots | 8.9 | 11.8 | 9.1 | 10.8 | 12.7 | 14.9 |
| (ii ′ ) three or more slot characters | 19.6 | 18.0 | 34.1 | 28.0 | 47.6 | 38.7 |
| Corpus | (a) | (b) | (c) | (d) | (e) | Destroyed | Edit-1 |
|---|---|---|---|---|---|---|---|
| Voynich, observed spaces | 0.197/5.7 | 0.243/4.3 | 0.199/5.8 | 0.167/2.0 | 0.067/0.8 | 90% | 1.12 |
| Voynich, weak spaces merged | 0.162/4.8 | 0.181/3.3 | 0.149/4.4 | 0.121/1.5 | 0.044/0.5 | 88% | 1.14 |
| Voynich, observed, raw EVA | 0.188/5.9 | 0.233/4.8 | 0.185/5.7 | 0.172/2.1 | 0.067/0.8 | 93% | 1.13 |
| Voynich, Currier A | 0.137/3.9 | 0.134/2.4 | 0.081/2.3 | 0.045/0.5 | / | 77% | 1.20 |
| Voynich, Currier B | 0.248/7.4 | 0.280/5.2 | 0.211/6.3 | 0.191/2.3 | 0.029/0.3 | 91% | 1.07 |
| Latin narrative | 0.033/0.8 | 0.220/3.4 | 0.174/4.3 | 0.268/3.3 | 0.326/4.0 | 78% | 0.43 |
| Stream | Order share | Types | Hapax |
|---|---|---|---|
| Bencao Beiyao (herbal), tonal | 5.40% | 686 | 20.3% |
| Bencao Beiyao (herbal), toneless | 5.23% | 335 | 9.6% |
| Three Kingdoms (narrative), tonal | 6.21% | 749 | 17.6% |
| Three Kingdoms (narrative), toneless | 6.42% | – | – |
| Voynichese, Currier A | 3,343 | 72.2% | |
| Voynichese, Currier B (22,871 tokens) | 4,840 | 68.6% |