Hermēs (Greek: 'Έρμης': 'pile of marker stones'), in Greek mythology, is the god of boundaries and of the travelers who cross them, of shepherds and cowherds, of orators, literature and poets, of athletics, of weights and measures and invention and commerce in general, of the cunning of thieves, and the messenger from the gods to humans. A lucky find was a hermaion. An interpreter who bridges the boundaries with strangers is a hermeneus. Hermes gives us our word "hermeneutics" for the art of interpreting hidden meaning.
A syncretic conflation of Hermes with the Egyptian god of wisdom Thoth produced the figure of Hermes Trismegistus, to whom a body of arcane lore was attributed in the Greco-Roman culture of Alexandria. The writings attributed to Hermes Trismegistus were edited and published in the Italian Renaissance.
Among the Hellenes, as the related word Herma ‘a boundary stone, crossing point’ would suggest, Hermes is the Spirit of Crossing-Over. As such he was seen to be manifest in any kind of interchange, transfer, transgressions, transcendence, transition, transit or traversal, all of which activities involve some form of crossing in some sense. This explains his connection with transitions in one’s fortunes, with the interchanges of goods, words and information involved in trade, interpreting, oratory, writing, with the way in which the wind may transfer objects from one place to another, and with the transition to the afterlife.
In Greek mythology Hermes and Dionysus are the youngest of the Olympian pantheon (illustration, right). Son of Zeus and a primordial nymph named Maia, Hermes was born in a cave on Mt. Cyllene in Peloponnesus, between Achaia and Arcadia. His origin on Mt. Cyllene explains the origin of an epithet for Hermēs: Hermēs Cylleneius. He was also referred to as Enagonios.
The Romans found that Hermes was equivalent to their characteristic god Mercury, who may have been the descendent of the Etruscan Turms. The Roman Mercury, with his bulging wallet of the goods of life, later absorbed the Dei Lucrii, early gods of commerce and wealth, and were referred to by that name. In the syncretic religious atmosphere of the Roman Empire, Hermes was combined with the Egyptian Anubis to form Hermanubis. In a similar fashion, the name Hermes Trismegistus was used later by alchemists and their like to refer to a syncretic god combining elements from Hermes and the Egyptian god Thoth.
Hermēs or Mercury was commonly identified by Roman observers with the Germanic god Wotan/Woden/Odin, hence Latin dies Mercurius corresponds to English Wednesday from Wodnes dæg 'Woden's day'.
The modern post office in Greece uses Hermēs as its symbol.
Though temples to Hermēs existed throughout Greece, a center of his cult was at Pheneos in Arcadia, where festivals in his honor were called Hermoea.
As a crosser of boundaries, Hermēs Psychopompos' ("conductor of the soul") was a psychopomp, meaning he brought newly-dead souls to the underworld, Hades. In the Homeric Hymn to Demeter Hermes conducts the Kore safely back to Demeter. He also brought dreams to living mortals.
Hermes as an inventor of fire is a parallel of the titan Prometheus. In addition to the syrinx and the lyre, Hermes invented many types of racing and the sport of boxing. In the 6th century the traditional bearded phallic Hermes was reimagined as an athletic youth (illustration, top right); statues of the new type of Hermēs stood at stadia and gymnasiums throughout Greece.