Modelling vagueness – A criteria-based system for the qualitative assessment of reading proposals for the deciphering of Classic Mayan hieroglyphs Franziska Diehr1, Sven Gronemeyer2, 3, Elisabeth Wagner2, Christian Prager2, Katja Diederichs2, Uwe Sikora1, Maximilian Brodhun1, Nikolai Grube2 1 State and University Library Göttingen, Germany 2 Department for Anthropology of the Americas, University of Bonn, Germany 3 Department of Archaeology and History, La Trobe University, Australia [email protected] Abstract office, located at the Department for the Anthropo- logy of the Americas, University of Bonn,3 works The project ‘Text Database and Diction- in close collaboration with the State and University ary of Classic Mayan’ aims at creating a Library Göttingen.4 Since 2014, the hieroglyphic machine-readable corpus of all Maya texts texts have been prepared, evaluated, and interpreted and compiling a dictionary on this basis. in interdisciplinary cooperation using methods and The characteristics of this complex writ- tools from the humanities and information techno- ing system pose particular challenges to logy (Prager, 2014c). research, resulting in contradictory and am- One result of this collaboration, and at the same biguous deciphering hypotheses. In this time an important milestone of the project, is the paper, we present a system for the qualitat- digital Sign Catalogue which is the subject of this ive evaluation of reading proposals that is paper. For the creation of a text corpus and a dic- integrated into a digital Sign Catalogue for tionary of an only partially understood language Mayan hieroglyphs, establishing a novel and script, a Sign Catalogue, an inventory of all concept for sign systematisation and clas- used signs, is an indispensable instrument. At the sification. The paper focuses in particular same time, the catalogue also forms the core com- on the modelling process and thus emphas- ponent for constructing a machine-readable text. ises the role of knowledge representation The project deals with a writing system that is only in digital humanities research. partially deciphered. The investigation of the script 1 Modelling vagueness in the Maya and language has produced numerous assumptions and interpretations about the reading of its signs. Dictionary project For a heuristic deciphering work, these reading hy- The not yet completely deciphered script of the pre- potheses are to be included for further investigation. Columbian Maya culture is the research subject During the development of the Sign Catalogue, a of the interdisciplinary project ‘Text Database and system for the qualitative evaluation of decipher- Dictionary of Classic Mayan’.1 The aim of this ment hypotheses and reading proposals was de- long-term project is to record the approximately veloped. Among other things, it offers assistance 10,000 known text carriers and their inscriptions with the linguistic analyses of the texts. The chal- in a machine-readable corpus and based on this lenge in modelling this system was to represent to compile a dictionary, which reflects the entire several reading proposals, as well as to determine vocabulary and its use in context (Prager, 2014b).2 the factors that led to the formulation of the respect- As a joint effort, the specially established project ive deciphering hypothesis. The goal of knowledge representation is also the explicit description of 1. http://mayadictionary.de 2. The project started in 2014 and is expected to end in 2028. the methods applied. This enables the scholar to It is funded by the North Rhine-Westphalian Academy of carry out analyses and draw conclusions on the Sciences and Arts http://www.awk.nrw.de and the Union of German Academies of Sciences and Humanities https: 3. https://www.iae.uni-bonn.de/ //www.akademienunion.de. 4. https://www.sub.uni-goettingen.de 33 Proceedings of the Workshop on Computational Methods in the Humanities 2018 (COMHUM 2018) Figure 2: Writing of Maya Hieroglyphs which is characterised by two main sign classes: logograms and syllabograms. Logograms stand for linguistic terms, like e.g. PAKAL for ‘shield’, and refer, with only a few exceptions, only to one Figure 1: Example for a Maya inscription denotation. Syllabograms represent single vowels and syllabic components and serve to write lex- ical and grammatical morphemes. They are also basis of the model. The modelling of reading pro- used as phonetic complements of logograms, as posals and their plausibility act as examples for in PAKAL-la. Words could thus also be written the representation of complex knowledge objects exclusively with syllabic signs pa-ka-la (Figure2), with interpretive character, as they are typical for but mostly, both sign classes were combined in research data in the humanities. In this context, writing (Diehr et al., 2017, 1186). the paper emphasizes the role of knowledge repres- entation in projects that are located in the digital The signs were arranged in almost rectangular humanities and considers the challenges posed by blocks. Such a hieroglyphic block probably cor- the modelling of vague and uncertain information. responds to the emic idea of a word. Within a block, the signs could be arranged in many differ- 2 Characteristics of Classic Maya ent ways. Depending on space requirements and writing aesthetics, they could merge, overlap, be infixed, or rotated. The blocks were usually arranged in Compared to other Mesoamerican writing systems, double columns and read from left to right and such as Isthmic or Aztec, Maya writing has a con- top to bottom. The sentences constructed this way siderably long time of use, about 2,000 years. The form complex texts with a syntax and structure first pre-Classic texts were written in the 3rd cen- still preserved in modern Mayan languages (Prager, tury B.C. The writing tradition reached its peak in 2014a). Maya writing shows a distinct calligraphic the Classic period (100 - 810 A.D.). The arrival of complexity, as we can observe a broad graphic vari- the Spaniards lead to a deep cut in Maya culture ability of signs. It allowed to write aesthetically that also affected the use of their writing. It was sophisticated texts without necessarily repeating only possible for the Maya to use it in secret. In the identical variants. For a linguistic expression, there underground, hieroglyphic writing continued until is not only a single graphic correspondence, but the late 17th century, and ceased to exist thereafter. usually several, sometimes very different, variants. It was only due to 18th and especially the 19th The bipartite syllabogram u could either be writ- century explorers who brought Maya texts back ten in its full form or alternatively with only one to light, and with that further and further into the of its two segments. These segments could also focus of research. To date, an estimated 10,000 be reduced or multiplied. As a further example, text carriers (Figure1) have survived, mainly mo- the syllablic sign yi shows how simple forms can numental inscriptions such as altars and stelae. Nu- be transformed into so-called head variants. Even merous texts can also be found on ceramics and diagnostic features (marked in Figure3) are not small artefacts, like jewellery, implements or boxes. present in all graph variants. It was even possible Of special importance are the codices written on to insert or parenthesise other graphs, as the ex- paper-like material, of which unfortunately only ample ma shows (Figure3). four have survived. The way in which variants are formed has not The Maya writing system is characterised by yet been the subject of systematic investigations an iconic character, hence labelled a hieroglyphic before. There are a few individual studies by Beyer script. Typologically it is a logo-syllabic system (1934a; 1934b; 1936; 1937) and Lacadena (1995, 34 Proceedings of the Workshop on Computational Methods in the Humanities 2018 (COMHUM 2018) of published sign inventories shows between 700 and 1,000 signs with a phonemic value. These comprise, according to own estimates, about 3,000 distinctive graph variants. 3 Sign catalogues as classification aids The study of the hieroglyphs is carried out on the basis of previously discovered text carriers. How- ever, many text carriers have been destroyed over time, are forgotten in archives and museums, hid- den in private collections, or have simply not yet been discovered. Therefore, there will always be a small number of signs that could not be invent- oried. On the other hand, it can be assumed that new discoveries will be made in the coming years. Early in 2018, the results of a large-scale aerial Lidar prospection in Guatemala were presented, Figure 3: Graph variants showing a much denser concentration of archaeolo- gical sites in the tropical lowlands than previously assumed, also implying a larger number of text 204 ff.) that investigate substitutions, rotation prin- carriers (Clyens, 2018). ciples, or symmetries. In the course of the pre- The discovery of new inscriptions and thus the paratory work for the digital Sign Catalogue, we discovery of previously unknown signs represents recognised for the first time that there are general a challenge for the classification of Maya signs. rules and principles for the formation of graphs Previous sign inventories could, of course, only which can be derived and defined by graphotactic consider the signs known at the time for a printed 5 analyses . In total, we have identified 45 individual publication. The discovery of new signs has to be variation principles that can be divided into nine anticipated in the digital Sign Catalogue, also a pos- classes (mono-, bi-, tri-, and variopartite, division, sible re-classification of already known signs. We animation head, animation figure, multiplication, therefore need flexible data management processes extraction). for new research results. Another feature is the polyvalence of signs. A Compared to other ancient languages and writ- single glyph can either be read as a logogram or a ing systems, the decipherment of Maya writing is syllabogram, depending on context.