POHUA/TLACHIA: a tool for the analysis of the images of Aztec writing /

Marc Thouvenot (CELIA, CNRS) ©

(Translation: Michel Besson)

Introduction
POHUA lets one:
- register data provided by a detailed analysis of the images of Aztec writing - from one or several documents - and of the Nahuatl words that are linked to them.
- present and print the data and the results in the form of synthetic documents.
- consult a part of the data.
- search through the whole of the information thus gathered, that is to say, to be able to ask the most complex questions.

The uninitiated user can avail himself of a permanent help that allows him at any time to know what the program expects as feedback from him, and especially by giving the definition of all the specific terms used by the program.

A/ Goal of the program

The word POHUA, a Nahuatl verb meaning " to count, to read ", expresses the aim of this program: to count and to present all the information provided by the analysis of the images, in order to synthesize it and to be able to read it. The detailed and systematic analysis of the images carries within itself the accumulation of a vast number of data (200 000 for the 2 367 glyphs of the Codex Xolotl), so that the use of a computer becomes rapidly necessary to treat them. On the other hand, since these systematic studies of the images of Aztec writing are barely beginning, since they date back only to the first publications by Joaquín Galarza, the ultimate goal - to be able to read the images - must go together with making available to everybody the sum of all the data in order to permit the mandatory verifications, validations, and comparisons. The role of POHUA is to replace the user for all the repetitive tasks and to present the complexity of these images under every possible angle.


B/ Method

This program is actually the mere systematisation and the automatization of all the operations which were carried out when analysing the glyphs of the Codex Xolotl, and when I created a relational data base to store the information thus obtained (Thouvenot, Marc (in press), Codex Xolotl, Etude d'une des composantes de son écriture: les glyphes. Dictionnaire des éléments constitutifs des glyphes, Atelier National de reproduction des thèses, 4300 p.).

 Analysis of the images
a) General principles
The methodological ideas behind the analysis, and thus behind the working of the program, are directly or indirectly expressed by most of the works of J. Galarza, and especially in his publications dedicated to the " Lienzos de Chiepetlan " and to the "Codex Mendoza " (Galarza, Joaquín 1972, Lienzos de Chiepetlan, México, M.A.E.F.M., 505 p. ; 1983a, Codex Mendoza. 1ère page: 2 recto. Méthode d'analyse, Paris, Institut d'Ethnologie, Archives et Documents, 114 p. ; 1983b, Codex Mendoza. 1ère Page. 2 recto. Lecture Nahuatl, Paris, Institut d'Ethnologie, Archives et Documents).
The first consists in regarding the Aztec codices as written manuscripts. This is apparently not a new idea, but it becomes so if one is to add that everything that is drawn on such a document is writing in itself. This conception brings us to a practice that entails that the level of analysis must be similar for everything that is on the page of a codex, whether it be a personage, a glyph or a link.
The second idea consists in asserting that all the codices from the Nahua region are documents written in Nahuatl and that they can transcribe all the characteristics of that language. This means that one must put in relation the drawings, all of them, with the Nahuatl language.
The third idea is a consequence of the first two: all the characteristics of the drawings must be observed and taken onto account since they constitute the very warp of the writing system. They are what J. Galarza calls the " qualities of the image ", that one must try and define and then bring together with the transcribed language, i.e. the Nahuatl. One of the direct consequences of this idea is the necessity of building up sheets of comparative drawings for each element. 
The fourth idea asserts that each element must be recognized and that its name must be pronounced since, as a rule, it is the name that provides the phonic values. The fact that one recognizes an element means that one has to try and define the relationship between that element and reality, while naming it means finding the Nahuatl name that could be used to designate what each drawing refers to.
Before describing how glyphs and personages can be analyzed, one must point out a general fact regarding the nature of the matter to be studied. These are drawings, and we use words in order to describe and analyse them. This can only be done at the cost of numerous reductions and errors. Even if the images belong to a conventional category, which drastically limits their potential realisations, the fact remains that, through the transcription of the image characteristics by way of words, one cannot avoid errors or oversights. However systematic the analysis, these two defects will always be present. Another problem is linked to the categorization, or classification. Every time such an operation is set in motion, one must remain conscious that there will always be limit cases for which the attribution to one category or another will be arbitrary to a certain degree. Inasmuch as possible, the main graphical divisions must be made from purely graphical criteria. These criteria must be obvious to anyone that would examine the document. We have always be very careful to dissociate the glyph analysis from the knowledge gained from their readings. This is not always possible, but in the field of Aztec writing, where uncertainties are more numerous than incontrovertible facts, the images are the only fixed elements, and any work must thus start with them and come back to them.

b) The stages in the analysis
The main stages are: 1) the encoding of the images; 2) the determination of the glyphs and of the personages, as well as the classification of the glyphs; 3) the study of their plastic qualities; 4) the determination, designation, and classification of the elements; 5) the search for and the analysis of the quotes. From the whole of the information thus gathered, one can then propose 6) readings and new words, and deduce 7) the phonic values, and to study and tackle the problem of 8) the direction of the reading.