One Snake or Two: The Symbols of Medicine

Carol R Froman & John E Skandalakis. The American Surgeon. Volume 74, Issue 4, April 2008.

The Caduceus (greek Kerykeion: herald’s wand) is an emblem consisting of two snakes symmetrically twined about a wand, bearing at its top a pair of wings. This emblem is widely used by health providers in North America. From time to time scholars question the propriety of using the caduceus as a symbol of the medical profession.

The question of propriety arises from the fact that the wand with two snakes was originally the attribute of the messenger of the Olympian gods: Hermes to the Greeks or Mercury to the Romans. It is not the stout staff bearing a single snake associated with Asklepios, the ancient god or folk hero of healing.

Snakes, Magic, and Medicine

The snake itself has a long history of divine and magical powers in many parts of the world. In esoteric Buddhism and in Hindu yogic practice, the serpent is the symbol of kundalini, the power of pure force. Throughout the Mediterranean world, the snake assumed mystical properties. In near Eastern archeological finds from 3100 BCE the twin-snake motif is displayed. As a magical figure, the snake is found in Egypt and in Babylonia; almost certainly its worship extends back to Neolithic times. It appeared as both the enemy of God in the book of Genesis (3:1-5), and as a healing symbol, the brass serpent of Moses, in the book of Numbers (21:8-9).

Creation epics of the Near and Far East depict the snake as both Agathodaemon and Kakodaemon, the good one and the evil one. The ancients saw potent symbols of these two aspects of underworld divinity in the reptilian world. The common poisonous snakes of the Mediterranean region are the Vipera aspis of Europe and the Cerastea cornuta of North Africa. In contrast, the nonpoisonous Elaphis aesculapii, a gentle and easily tamed, tree-climbing snake, was the household and temple spirit who served to keep down the population of mice. The snake was an avatar: representing in its poisonous role, death; and in its graceful movements and annual shedding of its skin, renewal, convalescence, and long life.

Medicine has been associated with serpent symbolism since humanity has recorded the art. Both archeological and literary evidence connect the snake and healing. The figure of Asklepios is usually portrayed with a snake and a staff, the attributes that identify him. Occasionally there is no staff, and the snake is coiled beside the seated god. A dog may also be present.


Whether Asklepios was a person, a folk hero, or a once-suppressed and later rejuvenated god is still open to discussion. Although Mycenaean inscriptions suggest the early worship of Asklepios, the poet Homer did not consider him a god, referring to him only as the “blameless physician” (Iliad IV: 184). According to Hesiod, Asklepios was the son of Apollo and a mortal woman, Coronis. While pregnant with Asklepios, Coronis was about to marry a mortal. Artemis, Apollo’s twin sister, was infuriated and killed the woman. Apollo saved the child from his mother’s dead body and turned him over to Chiron, the centaur, to be taught the arts of healing and hunting (Homerica: Hymn 14).

During the later development of the Asklepian cult, there were many other legends. In the temples where patients were treated through “incubation sleep,” the sacred snake was believed to provide actual therapy to the dreaming sufferers. To the worshipers of Asklepios, the snake was not a mere symbol: it was a real snake.

Hermes and the Caduceus

When the Greeks founded new communities in Egypt, they began to identify their gods with those of the Egyptians. By shared attributes of cleverness and inventiveness, the Egyptian god Thoth was linked to Hermes. From this union arose the figure of the sage Hermes Trismegistus (Hermes three-times-great), the putative author of works of philosophy and alchemy which were gathered together in a single corpus given the title Hermetica.

The caduceus of Hermes, bearing two snakes, was said to have been a gift from Apollo to Hermes for his invention of the lyre. The gift carried with it the duties of herald and messenger of the Olympian gods. Two stories are told of its significance. As an attribute of fertility, the two snakes have been considered to be male and female, copulating. Other tales suggest that the snakes were fighting until they were separated by the wand, suggesting the neutral position of the messenger or herald who intervenes on behalf of the gods. In this capacity, Hermes also became the figure of the noncombatant.

The final step in the development of the caduceus was the addition of wings to the wand.10 It has been suggested that the wings are those of the sun god Horus, the Egyptian equivalent of Apollo. The wings are often seen attached to the sandals or to the helmet of Hermes instead of to his wand. The wings bear no relation to medicine; they refer to the duties of Hermes as the swift messenger. This attribute has been used to represent the postal service in many countries.

Historical Responses

With the rise of Christianity, the Olympian gods and their symbols were suppressed, although the last Asklepian temple survived in Athens up to the 5th century CE. Despite clerical opposition, the worship of Asklepios outlasted that of the other Olympian gods. Asklepios was less repugnant to some early Christians (including Augustine) than were other pagan gods because of his blameless life. Conversely, his worship was seen by some Church Fathers (Jerome, Clement of Alexandria) as a Satan-inspired competition with the worship of Christ the Physician. Augustine associated a figure he variously called Hermes and Hermes Trismegistus with wisdom because of “statements that in ancient times he predicted the triumph of Christianity.”

With very few exceptions, symbols associated with Greco-Roman civilization disappeared in the Middle Ages, and reappeared only in the 16th century. Schouten described the ceiling of a palace built in Rome in 1593 by Frederico Zuccari, in which Asklepios appears partially enthroned with his staff and snake. The names of Galen, Avicenna, and Hippocrates are inscribed below.

At about the same time, the double snake and rod (without wings) appeared as a printer’s device used by Erhard Ratdolt (1486) and Johann Frobel (1518); the symbolism of Frobel’s design perhaps related to the Biblical injunction: “Be ye wise as serpents and harmless as doves” (Matthew 10:16). Other 16th century examples are known. William Harvey’s arms bore a crest with a wand and two snakes as did the arms of Sir William Butts, physician to Henry VIII. The double snake also served as the symbol of the metallic element mercury for the alchemists and the planet Mercury for the astrologers. Schouten catalogued numerous examples of medically-specific images from this era depicting either the single Asklepian snake or the double Hermetic snakes.

Despite the nonmedical attributes of the caduceus, it was adopted (complete with wings) in 1856 for the badge of the Hospital Stewards of the United States Army and later, together with a symbolic anchor, for the insignia of the United States Public Health Service. The coat of arms of the U.S. Army Medical Department has borne the single-snake rod since 1818; however, in 1902, the caduceus was adopted by the Army Medical Corps. In 1912, the American Medical Association adopted the ancient staff and snake of Asklepios, which it preserves today.

Caduceus or Asklepian Staff?

How can we explain the persistent use of the Hermetic device for the medical arts, or, conversely, understand where and why Asklepios’ symbol has been used? Several theories have been proposed. They fall into three categories:

1) There is a legitimate reason for the use of the caduceus in military medicine. Hermes the messenger and herald was a neutral figure, authorized to gather the bodies of the dead and minister to the wounded, respected by opposing sides. In this context, his wand represents the essentially noncombatant role of the military physician.

2) The Asklepian and Hermetic symbols arose from a common Babylonian/Egyptian precursor and can be categorized as essentially the same. There is a common origin of the two symbols, and an expansive range of concomitant sociocultural allusions. The wand and snakes of Mercury most likely reached medicine by way of alchemy and pharmacy around the 15th century. As Wilcox noted, “From the beginning of the 17th century, the figure of Asklepios … was used only in a medical context, whereas the caduceus, although used by some medical organizations, was associated with other fields, especially commerce, communications, chemistry, and pharmacy.” In this context, it is interesting to note that the etymological root of merchant (English), marchand (French), mercante (Italian), and mercader (Spanish) is Mercury.

3) The two symbols became confused by the U.S. military establishment in 1856 and in 1902 simply through ignorance. Garrison, the noted medical historian, penned a strong denial of Tyson’s paper, complaining that the trouble with classical scholarship was its “bothering with petty details”: an odd remark from a physician and historian. Whether the military establishment had in mind the concept of the noncombatant role of the physician, or was, as Tyson suggests, merely ignorant may never be settled. We do not have the deliberations attendant on the adoption of the insignia. Although conscious selection of the caduceus by the Army can be explained, a further explanation must be sought for the numerous emblems with double snakes which appeared on coats of arms and in paintings of the 16th and 17th centuries.

The rough staff and single snake were realistically carved on the ancient statues of Asklepios; they were not stylized representations. The ancient sculptor knew what he should carve; he could not design gods to suit his fancy. However, the Olympian gods resurrected in the Renaissance were more creatures of art than faith. The artist no longer prayed to a friendly household snake; snakes were merely unpleasant animals. Thus, released from the bonds of verisimilitude, the attributes of the gods became subject to noniconographic variations based on taste and aesthetics. If you idly draw a snake twined about a stick, you may feel almost compelled to add a second snake: not for tradition, but for symmetry. The once-real snake clinging to the staff now becomes a pair of graceful tapering spirals around a slender shaft. Asklepios himself is no longer leaning on the staff, so it may become smaller and be held as a wand. The wand may become a torch; it may grow wings that add grace and balance to an otherwise simple design. Its symbolic function has become secondary to its function as decoration.

It was during this later post-Reformation reincarnation of the gods that confusion entered, perhaps not from ignorance, but from the absence of the piety that existed when the Olympian gods reigned. The snake(s)-and-standard became a clever trademark to be tailored by the artist for a practitioner of the healing arts who was removed from the rites of the Asklepian temple by more than a thousand years.

The concept of the healing power of the snake seems to have all but vanished in our culture. However, we cannot put ourselves completely outside the spirit of our ancestors. Humans have retained a partly rational and partly subconscious horror of snakes. The rational fear, like some few others, persists, although it is no longer adaptive. The post-Freudian awareness of the phallic associations of the snake form taps a very ancient psychic element, as significant today as in the past. Harris and Wilson have pointed out that we feel far less strongly about far more important dangers of modern life.


Should Medicine be symbolically linked to the Greco-Roman god associated with “thieves, merchants and messengers”, or to the figure of the “blameless physician”? In 1535, Andres de Laguna of Segovia prefaced his Anatomical Procedures with a plea: “Although I keep silent about other professions I shall not forget my own; who does not grieve for the art of medicine, which in an earlier and happier era was practiced by Apollo, Aesculapius, Chiron, and Hippocrates … the cause of this calamity and pestilence is the physicians and beggarly professors. For who indeed are possessed by so great and insatiable lust for money, fame, and glory?”

Could it be true that “the selection of the caduceus as the emblem of medicine may have been an ominous forecast of the emerging view of Medicine seemingly held by much of the general public and by many politicians?” Was Khouzam correct in stating: “It is no wonder that the caduceus has been transformed into a dollar sign in the public mind”?

Of course, we disagree with Khouzam. We wish to emphasize that the medical profession of today is formed by surgeons, physicians, and allied medical personnel who are motivated by a philanthropic spirit, a group which does not deny aid to the poor. Hippocrates and Asklepios would be proud of those who stand ready day or night to help sick human beings. To answer the negative commentators, we would say with a strong voice to the surgeons and doctors of the 21st century: “Follow the philanthropic pathway, as I know that you already do. Know your surgical anatomy, and practice the best medicine and surgery. Learn the history of Medicine, and keep on going!”