Hermes Trismegistus, the “thrice great,” demands place at the beginning of this collection, not for reasons of “actual” existence, scientific dating, and absolute chronology, but by virtue of the deeply rooted psychological appeal of myth, legend, and tradition. Long identified as the Greek counterpart of the Egyptian Thoth, the god of wisdom, Hermes was known throughout the ancient world both for his religious and philosophical wisdom and his seer-like understanding of the most obscure areas of human speculation and experience: astrology, magic, the secrets of plants and stones, and alchemy. Because he was also credited with giving laws and letters to the Egyptians, his triple greatness consisted of preeminence as priest, philosopher, and king. These roles, combined with notions of Hermes’ extreme antiquity – his lifetime was variously calculated according to the times of Atlas, Prometheus, Orpheus, Noah and Moses – assured the eponymous founder of hermeticism a high place in the wisdom tradition that extended down to Plato.

As might be expected, an extraordinary number of writings were attributed to Hermes, including the “philosophical” or “theoretical” treatises that comprise the Corpus Hermeticum along with the Latin Asclepius. In addition, a vast number of “technical” hermetica – treatises and fragments on the practical aspects of astrology, alchemy, sympathetic magic, talismans, invocations, and the like – passed under his name, including the famously enigmatic Emerald Table (or Tabula Smaragdina) printed below. In this brief tract the secrets of the preparation of the philosopher's stone were thought to be cryptically set forth on an emerald tablet.