The Voynich Manuscript: A Hypothesis of a Dual Writing System and Cyclical (Base-12) Numeration

Abstract The Voynich Manuscript (MS 408) remains one of the most studied yet undeciphered medieval documents. Most previous approaches implicitly assume that all glyphs belong to a single alphabetic or linguistic system. This paper proposes an alternative, testable structural hypothesis: that the manuscript employs at least two functionally distinct systems of signs — an alphabetic (phonetic or linguistic) layer and a cyclical or numerical layer, potentially operating within a duodecimal (base-12) framework. The study does not attempt semantic decipherment. Instead, it focuses on positional distribution, frequency analysis, thematic correlation, and Markov-chain-based transition modeling across the first 116 folios. Results indicate that a limited subset of glyphs exhibits strong positional constraints, sequential behavior, and reset patterns inconsistent with alphabetic usage. These symbols appear with significantly higher frequency in astronomical and cosmological sections than in botanical sections. When the proposed cyclical symbols are treated as a separate functional class, statistical analysis reveals closed low-entropy chains and an estimated reduction of overall textual entropy by approximately 12–18%. Cycle lengths cluster around 11–13 steps, with a dominant mode of twelve, consistent with medieval astrological and calendrical traditions. The paper argues that prior statistical models may have conflated alphabetic and numerical elements, thereby obscuring underlying structure. The proposed framework is explicitly falsifiable and intended as a methodological contribution rather than a definitive interpretation. All claims are presented with the aim of encouraging independent replication, critique, and further interdisciplinary research.