A Timeline of the Decans: From Egyptian Astronomical Timekeeping to Greco-Roman Melothesia

Abstract

The decans were a set of thirty-six stars or constellations selected by the Egyptians in the First Intermediate Period as a means of marking the progression of the hours during the night. The rising of each decan on the horizon would mark the beginning of a new hour. The decans were depicted most often by the Egyptians in a funerary context, which led scholars to believe their initial function was not just astronomical but deeply religious as well. Once Egypt became colonized by Hellenistic rulers, the decans were adapted into the imported Babylonian zodiac. Once incorporated into the Hellenistic astrological system, which synthesized elements of both Egypt and Mesopotamia, the decans were believed to influence human health through the bonds of cosmic sympathy – the idea that all celestial bodies impacted human life in one way or another. The decans were each assigned to various sub-sections of the human body in a practice called melothesia. Once this assignment was established, a tradition of creating medical amulets emerged, allowing individuals to create folk remedies to alleviate disease and injury. The purpose of this paper is to review, synthesize, and contextualize the existent research on the decans.