Hermes Trismegistus (“the thrice greatest Hermes”), an honorific designation of the Egyptian Hermes, i.e. Thoth (q.v.), the god of wisdom. In late hieroglyphic the name of Thoth often has the epithet “the twice very great,” sometimes “the thrice very great”; in the popular language (demotic) the corresponding epithet is “the five times very great,” found as early as the 3rd century B.C. Greek translations give ὁ μέγας καὶ μέγας and μέγιστος: τρίσμεγας occurs in a late magical text. ὁ τρισμέγιστος has not yet been found earlier than the 2nd century A.D., but there can now be no doubt of its origin in the above Egyptian epithets.
Thoth was “the scribe of the gods,” “Lord of divine words,” and to Hermes was attributed the authorship of all the strictly sacred books generally called by Greek authors Hermetic. These, according to Clemens Alexandrinus, our sole ancient authority (Strom. vi. p. 268 et seq.), were forty-two in number, and were subdivided into six divisions, of which the first, containing ten books, was in charge of the “prophet” and dealt with laws, deities and the education of priests; the second, consisting of the ten books of the stolistes, the official whose duty it was to dress and ornament the statues of the gods, treated of sacrifices and offerings, prayers, hymns, festive processions; the third, of the “hierogrammatist,” also in ten books, was called “hieroglyphics,” and was a repertory of cosmographical, geographical and topographical information; the four books of the “horoscopus” were devoted to astronomy and astrology; the two books of the “chanter” contained respectively a collection of songs in honour of the gods and a description of the royal life and its duties; while the sixth and last division, consisting of the six books of the “pastophorus,” was medical. Clemens’s statement cannot be contradicted. Works are extant in papyri and on temple walls, treating of geography, astronomy, ritual, myths, medicine, &c. It is probable that the native priests would have been ready to ascribe the authorship or inspiration, as well as the care and protection of all their books of sacred lore to Thoth, although there were a goddess of writing (Seshit), and the ancient deified scribes Imuthes and Amenophis, and later inspired doctors Petosiris, Nechepso, &c., to be reckoned with; there are indeed some definite traces of such an attribution extant in individual cases. Whether a canon of such books was ever established, even in the latest times, may be seriously doubted. We know, however, that the vizier of Upper Egypt (at Thebes) in the eighteenth dynasty, had 40 (not 42) parchment rolls laid before him as he sat in the hall of audience. Unfortunately we have no hint of their contents. Forty-two was the number of divine assessors at the judgment of the dead before Osiris, and was the standard number of the nomes or counties in Egypt.
The name of Hermes seems during the 3rd and following centuries to have been regarded as a convenient pseudonym to place at the head of the numerous syncretistic writings in which it was sought to combine Neo-Platonic philosophy, Philonic Judaism and cabalistic theosophy, and so provide the world with some acceptable substitute for the Christianity which had even at that time begun to give indications of the ascendancy it was destined afterwards to attain. Of these pseudepigraphic Hermetic writings some have come down to us in the original Greek; others survive in Latin or Arabic translations; but the majority appear to have perished. That which is best known and has been most frequently edited is the Ποιμάνδρης sive De potestate et sapientia divina (Ποιμάνδρης being the Divine Intelligence, ποιμὴν ἀνδρῶν), which consists of fifteen chapters treating of such subjects as the nature of God, the origin of the world, the creation and fall of man, and the divine illumination which is the sole means of his deliverance. The editio princeps appeared in Paris in 1554; there is also an edition by G. Parthey (1854); the work has also been translated into German by D. Tiedemann (1781). Other Hermetic writings which have been preserved, and which have been for the most part collected by Patricius in the Nova de universis philosophia (1593), are (in Greek) Ἰατρομαθηματικά πρὸς Ἄμμωνα Αἰγύπτιον, Περὶ κατακλίσεως νοσούντων περιγνωστικά, Ἐκ τῆς μαθηματικῆς ἐπιστήμης πρὸς Ἄμμωνα: (in Latin) Aphorismi sive Centiloquium, Cyranides; (in Arabic, but doubtless from a Greek original) an address to the human soul, which has been translated by H. L. Fleischer (An die menschliche Seele, 1870).
The connexion of the name of Hermes with alchemy will explain what is meant by hermetic sealing, and will account for the use of the phrase “hermetic medicine” by Paracelsus, as also for the so-called “hermetic freemasonry” of the middle ages.
Besides Thoth, Anubis (q.v.) was constantly identified with Hermes; see also Horus.
See Ursinus, De Zoroastre, Hermete, &c. (Nuremberg, 1661); Nicolas Lenglet-Dufresnoy, L’Histoire de la philosophie hermétique (Paris, 1742); Baumgarten-Crusius, De librorum hermeticorum origine atque indole (Jena, 1827); B. J. Hilgers, De Hermetis Trismegisti Poëmandro (1855); R. Ménard, Hermès Trismégiste, traduction complète, précédée d’une étude sur l’origine des livres hermétiques (1866); R. Pietschmann, Hermes Trismegistus, nach ägyptischen, griechischen, und orientalischen Überlieferungen (1875); R. Reitzenstein, Poimandres, Studien zur griechisch-ägyptischen und frühchristlichen Literatur (Leipzig, 1904); G. R. S. Mead, Thrice Greatest Hermes (1907), introduction and translation.