Have you ever noticed that two different symbols are commonly used to represent the medical profession? If yes, then you might be wondering which of the two is the true symbol of medicine. These symbols–the Rod of Asclepius and the Caduceus–have long been an exciting yet confusing topic of debate. The story, which started as early as 1200 BC, has evolved and undergone many changes, but nevertheless survived misconceptions so that the truth has been preserved. Unfortunately, many healthcare professionals, medical students, and the general public are oblivious to this fact. These two different symbols have two different origins, and by implication, two different meanings. We ought to know which of them is the true symbol of medicine not only because of the interesting history, but because, whether consciously or unconsciously, we are associated with the meanings of the symbols we use. It is not just what we presume them to be, but what their origins depict that matters. Hence, to unravel the mystery surrounding the Rod of Asclepius and the Caduceus, we must return to their beginnings.
Asclepius (also Aesculapius) was the Greek god of medicine. He was the son of Apollo, the Greek god of healing. The Greco-Roman medical tradition symbolized Asclepius as the ideal Greek physician; that is, one with integrity, personal sacrifice, and compassion. Asclepius was killed by his grandfather, Zeus, with a thunderbolt because his healing power prevented people from passing onto the underworld. Many early Greek physicians claim direct descent from Asclepius. Even Hippocrates, the father of medicine, proudly claimed descent from him through Poldaleiros, the son of Asclepius. The opening lines of the Hippocratic Oath clearly reveal this as it begins with: “I swear by Apollo Physician and Asclepius…”
From ancient times, the Rod of Asclepius was widely displayed on statues, coins, and physician rings. Several myths describe how this rod was formed. One of the most popular tales claims that it was when Asclepius was examining a man, Glaukos, whom Zeus had recently struck dead with a thunderbolt, that a snake slithered into the room and startled Asclepius, who reacted by killing it with a blow from his staff. Asclepius was subsequently surprised by the arrival of a second snake, which placed certain herbs in the mouth of the dead snake and revived it to life. Quickly deducing this lesson, Asclepius revived Glaukos with the same herbs, and, as a mark of honour, he adopted a snake entwined about a rod as his emblem. The use of this symbol was very popular throughout antiquity, and it is still used today by most health institutions, including, but not limited to, the American Medical Association, the British Medical Association, the World Medical Association, the U.S. Air Force Medical Service, and the World Health Organization. How then did the Caduceus come about? Well, the Caduceus appeared later on, and its story is two-sided–the origin and a huge mistake.
The Caduceus was originally the staff of Hermes (Latin, Mercury), the Greek god of merchants, thieves, and travellers. Hermes was the son of Maia and Zeus. On the very day he was born, he offended his step brother, Apollo, by stealing his precious cattle, which he hid in a cave. He sacrificed two of the cattle and a tortoise whose shell he made into a lyre by stringing it with cords from the cattle. Having discovered the thief by divination, Apollo reported Hermes to Maia, but Maia only showed him ‘innocent’ Hermes still asleep in his cradle. Infuriated, Apollo took Hermes to Zeus, but his anger was quelled on the way by the enchanting music of the lyre. Consequently, Apollo gave Hermes the cattle in exchange for the musical instrument. Hermes later made a shepherd’s pipe, and Apollo, again enchanted by its music, exchanged his golden wand, which he used to herd cattle, for the pipe. The wand is called ‘Caduceus’ in Latin, and Apollo is said to have described it as “the wondrous staff of abundance and wealth which is not subject to death and will protect thee.”
According to legend, Hermes, in an attempt to separate two fighting snakes, drove his wand into the ground between them; the snakes then wrapped themselves around the wand peacefully, thus forming the Caduceus symbol. Hermes was later recognized as the peacemaker between Priam and Achilles, and, by Imperial Roman Times, the peace-making role of Caduceus of Herms was firmly established. The Roman legions used an object that resemble the Caduceus to identify non-combatants on the battleground. However, wings, analogous to the winged traveling hat and sandals of Hermes, were not added to the Caduceus until around 250 BC. Years later, in the 19th century, John Churchill of London, the prolific medical publisher, used a Caducean printer’s mark on the title page of many of the medical and scientific books he exported to the United States. Many claim that Churchill did not associate this symbol with medicine, but that his desire was to unite medicine and literature since he labelled the two serpents ‘medicina’ and ‘literis’, and gave the symbol the motto, ‘Irrupta Tenet Copula’ (unbreakable bond unites). In the United States, however, an erroneous mental connection between Churchill’s Caduceus and medical practice seemed to grow and from there, came the huge mistake.
It began with the U.S. Army Medical Corps (USAMC). In March 1902, Captain Frederick Reynolds, an assistant surgeon, erroneously suggested the establishment of a new uniform code with the Caduceus symbol for the USAMC. It was apparent that he was unaware of the distinction between the Caduceus and Asclepius because he recommended the combined use of the ‘cock of Asclepius’ and the Caduceus. Realizing this, the Surgeon General, G.W. Sternberg, outrightly dismissed his request. But Captain Reynolds was persistent. Later that year, he sent a second letter to the new Surgeon General, W.H. Forwood; this time, it was approved. Thus, on 17 July 1902, the ‘Caduceus of Gold’ became the insignia of the USAMC. This faux pas did not go unnoticed. In 1917, Lieutenant Colonel McCulloch, the librarian to the Surgeon General, discovered original documents revealing that the U.S. Army Medical Department (USAMEDD) adopted the Asclepius as far back as 1818. McCulloch lamented, but it was too late–the Caduceus lingered, seeping its way into medicine. Today, the Caduceus is used by the U.S. Navy Medical Service, many pharmaceutical companies, health institutions, physicians, and the general public.
Not knowing the history of these symbols have led to many fantastic presumptions. For example, many have wondered why such a dangerous creature as a snake is used to symbolize medicine, but presumptuously link it to the Biblical bronze snake attached to a pole by Moses, which anyone who was bitten by a poisonous snake looked at for healing. Another presumption is that snakes moult or shed their skin, indicating healing and longevity. The ability of snakes to change quickly from sluggishness to activeness has also been associated with the power to recover from illness. Moreover, snake venom has been found to have many therapeutic benefits. Unfortunately, these presumptions have blinded many from the truth. The popularity of the Caduceus nowadays also has underlying reasons. One is that it is aesthetically more appealing, another is that the symmetry is more balanced than a single snake and the last is its widespread adoption (often ignorantly) by pharmaceutical companies, medical equipment manufacturers, private hospitals, health institutions, and medical publishers.
Having unravelled the mystery surrounding Asclepius and Caduceus, we are now left to decide which of them is the true symbol of medicine. Asclepius, the Greek god of medicine, was seen as the ideal Greek Physician – one with integrity, personal sacrifice, and compassion. Contrastingly, Hermes was the Greek god of merchants, thieves, and travellers although he played a role as a mediator. The Rod of Asclepius has been in existence for over two millennia, whereas the Caduceus became a popular medical symbol only in the early 20th century. Lastly, the adoption of the Caduceus was accidental. Altogether, these leads us to conclude that the Rod of Asclepius is indeed the true symbol of medicine.