The Aztecs and Mixtecs used ancient, Mesoamerican calendrical systems in divinatory manuscripts to predict, foretell, and recount past and future events. There are several different calendars on codices that were recorded in different cultural contexts and from different artists/scribes, but the numerical system itself is almost entirely consistent. The 260-day cycle is called the tonalpohualli, which contains a twenty-day cycle that repeats thirteen times (called a trecena); each day is called a tonalli, which individually represent various pre-determined fates that are aligned with ancient myth and ritual. In addition to the accompanying myths, all twenty days are assigned particular symbols that correspond to various deities that govern each day and determine its fate (seen in Plate 56). It is apparent that these numerical and pictographic representations of time not only gave them a way to preserve their cultures, histories and traditions, but also provided religious and cultural narratives for those who studied them.
Quetzalcoatl’s epic myth exemplifies a “conventional semasiographic system,” because it represents the Aztec calendrical cycle through specific conventions connected to spatial relationships and a fixed set of symbols.  Pictographic symbols, like a monkey representing an actual monkey, are literal, whereas ideographs capture philosophical ideas within a few symbols or less. Pictographic and ideographic symbols combine to create ‘semasiographic language,’ which is used, in this case, to illustrate the widespread attempt to maintain a philosophical balance between religious ideologies and physical truth or meaning.
Quetzalcoatl existed as a godly being that also displayed human behavior, therefore designating a connection between the heavens and the earth. His character tread dangerously among the fine divide between myth and reality, earth and sky, godliness and humanity, heaven and the underworld. Similar to the bodies that bowed to worship Quetzalcoatl’s heroic spirit, the wind deity’s physical form is less than perfect because of the challenges he faced throughout his journey. Mesoamerican communities continuously pioneered pathways to distant lands as they simultaneously braved imminent mortality and fought for survival on an almost-daily basis.  While Quetzalcoatl undertook his metaphorical excursion, the Mesoamericans followed a similar path through different parts of the earth that remained undiscovered. He underwent both a physical and spiritual transformation that aligned with the ever-changing lifestyles of Mesoamerican communities and their general acceptance of life’s instability.
There are many existing translations of the ancient myths surrounding this legendary figure, most of which are influenced by European Christian ideologies because of the Conquest. However, John Beirhorst has edited and translated most of these pre-existing accounts and compiled more modern interpretations of the texts to provide a more structured legend. According to these texts, the deity was born on earth in the Toltec period (A.D. 600-1100) as a prince called Topiltzin.  He lived a life of piety until transforming into a godly figure and becoming part of the heavens where the “bigger” gods lived and oversaw his actions. He was now called Quetzalcoatl, (wind deity/feathered serpent) and dove headfirst into the mysterious underworld in order to fill the earth with people, but tripped on his way down. The gods of the underworld chewed on the bones as he sailed swiftly through multiple sacred dominions. Bierhorst divided Quetzalcoatl’s journey into four fragments, which directly correspond to Quetzalcoatl’s journey in the Borgia; they are called “A – the Restoration of Life,” “B – the Ceremonial Fire,” “C – A Cycle of Transformation,” “D – the Fall of Tollan,” and “E – a Song of Survival.”  My plan for research is to align these fragments, along with other accounts, to Quetzalcoatl’s journey in the Codex Borgia, specifically plates 29-38.
As Quetzalcoatl travels through the many realms of the underworld, he wears different disguises/masks and is transported through stylized portals that signify the unique worlds in which he enters and the gods who preside over those realms. In plate 56,Quetzalcoatl is represented in his truest, most godly form. Mictlantecuhtli becomes a portal through which he is to dive into the earth; his head is turned upside down and is flanked by the decorative skirts that each deity wears above. Their identities are merged and Quetzalcoatl experiences his first character mutation. This visual juxtaposition exemplifies the “antithesis of life and death,” since Quetzalcoatl created life and Mictlantecuhtli received death. 
 Boone,Elizabeth H. Writing without words: alternative literacies in Mesoamerica and the Andes. Duke University Press, 1994. pp. 14-17.  Scott O’Mack, Ethnohistory 38 (1991): p. 17  John Bierhorst, edited and trans., Four Masterworks of American Indian Literature: Quetzalcoatl/the Ritual of Condolence/Cuceb/The Night Chant (New York: Farrar, Straus and Giroux, 1974).  John Bierhorst, edited and trans., Four Masterworks of American Indian Literature, p.8  Boone,Elizabeth H. Writing without words, Duke University Press, 1994.
 Boone,Elizabeth H. Writing without words: alternative literacies in Mesoamerica and the Andes. Duke University Press, 1994. pp. 14-17.
 Scott O’Mack, Ethnohistory 38 (1991): p. 17
 John Bierhorst, edited and trans., Four Masterworks of American Indian Literature: Quetzalcoatl/the Ritual of Condolence/Cuceb/The Night Chant (New York: Farrar, Straus and Giroux, 1974).
 John Bierhorst, edited and trans., Four Masterworks of American Indian Literature, p.8
 Boone,Elizabeth H. Writing without words, Duke University Press, 1994.