Wing-footed Mercury/Hermes holding a caduceus. Fountain statue at Christchurch College Oxford.
Photo credit J White
The image of serpents wrapped around a staff is a familiar one in the medical field, decorating pharmaceutical packaging and hospitals alike. Snakes bites are generally bad news, which might make it seem ill-fitting as the symbol of the medical profession, but this ancient emblem actually has a long association with health, fertility, and with science and commerce.
There are actually two versions of the symbol of snake and staff. The winged version is known as a caduceus, usually depicted as carried by the Olympian god Hermes and/or Roman god Mercury. In Greek mythology, Hermes was a messenger between the gods and humans (which explains the wings) and a guide to the underworld (which explains the staff). Hermes was also the patron of travellers, which makes his connection to medicine somewhat appropriate, for in ancient times doctors would have had to travel great distances on foot in order to visit their patients.
In one version of Hermes' myth, he is given the staff by Apollo, the god of healing . In another version, he receives the staff from Zeus, the king of the gods, which is entwined with two white ribbons. The ribbons were later replaced by serpents, as another story tells us that Hermes used the stick to separate two fighting snakes , who then coiled around his staff and remained there in balanced harmony.
Rod or Staff?
Another, earlier depiction of the medical symbol is the 'Rod of Asclepius', which has no wings and only one snake. Asclepius, the son of Apollo and the human princess Coronis, is the Greek demigod of medicine . According to mythology, he was able to restore the health of the sick and bring the dead back to life.
In one telling, Zeus killed Asclepius with a thunderbolt for disrupting the natural order of the world by reviving the dead, while another version states that Zeus killed him as punishment for accepting money in exchange for conducting a resurrection. After he died, Zeus placed Asclepius among the stars as the constellation Ophiuchus, or "the serpent bearer."
The Greeks regarded snakes as sacred and used them in healing rituals to honor Asclepius, as snake venom was thought to be remedial, and the snake's skin-shedding was viewed as a symbol of rebirth and renewal.
A timeline depiction of the stages and God-associations that The Caduceus has moved through:
Ningizzida - Sumerian god of fertility & healing Mesopotamia – 3000BC
Thoth - Egyptian god of science, mathematics, healing, medicine & wisdom
Iris - Greek goddess, messenger from gods, of the Rainbow - hence 'iridescent'
Hermes - Greek, messenger from gods (thus the wings), associated with commerce, thieves, sports/athletes, travellers and boundary crossings, invention, weights and measures and had a reputation as a trickster. He was an Olympian god and so had great strength and prowess.
Mercury - Roman equivalent of Hermes
The caduceus has become confused with the 'Rod of Asclepius' This rod has a single snake twined around a staff with no wings.
Asclepius - Greek god of medical intervention
The Caduceus was used as a printer’s mark for early publishers of medical books to show that they were messengers of Hermes, god of commerce.
In 1902 the USA Army Medical Department adopted The Caduceus (rather than the Rod of Ascelpius) as its symbol. This has come to be associated with medicine today.