Mistakes with Snakes: Medicine, Commerce, Confusion

2–21–17, Adil

When you guys see healthcare-related organizations, you will frequently see one of these symbols:

For example, the logo of the United States Public Health Service:

And here’s the logo for the World Health Organization (WHO):

But, it turns out that one of these is actually the wrong symbol for medicine.

The correct symbol is the Rod of Asclepius, with one snake and no wings above the staff. In the world of Greek mythology, the choice of the Rod of Asclepius is a sensible one, as Asclepius — the son of Apollo — was the Greek god of healing and medicine. This choice is also an ancient one; by the 6th century BCE, there were hundreds of Asklepions — temples complexes often for medical practices — around the Greco-Roman. Asclepius was viewed as the patron of physicians, especially those who took care of the poor and vulnerable.

Then what the heck is the Caduceus? In Greco-Egyptian mythology, it is in the staff carried by Hermes Trismegistus (aka Mercury in Roman mythology). This Hermes fellow was a messenger of the gods and conveyor of dreams… but also the protector of merchants, commerce, and thieves. Even better, he was in fact the conductor of the dead to the world of the afterlife. So, he wouldn’t be my top choice for the symbol of the profession dedicated to keeping people alive.

This error pervades many medical organizations, especially in North America. In fact, in one United States study that analyzed 242 healthcare logos from the 1970s and 80s that included either the Rod of Asclepius or Caduceus, it was found that 38% of professional medical organizations and 76% of commercial organizations used the Caduceus (a statistically significant difference; Friedlander 1992)! The author argues that this actually makes sense, since commercial medical organizations (e.g. those related to for-profit hospitals, medical employment agencies, insurance companies, commercial labs, etc.) have to do more with business than medicine. But this really seems like a convenient explanation for what is truly a mistake. Personally, I am inclined to believe the alternate hypothesis that these commercial entities are unfamiliar with the meaning of the two symbols, and simply chose the more symmetric, aesthetically-pleasing version. I have no explanation for the 38% of the professional medical organizations… they really goofed.

Where does this confusion come from, then? One idea is that the prolific medical text publisher John Churchill of London used the Caduceus all over a bunch of his texts in the 19th century, and with the presence of the symbol on such respected medical texts, it came to be associated with medicine. But Churchill also used the Rod of Asclepius in his texts; accordingly, some argue he deliberately chose the Caduceus as a logo for his printing business and had no intention of spreading it as a medical symbol. Another hypothesis is that the confusion stems from a couple of buffoons at the US Army Medical Corps. Assistant surgeon Captain Frederick Reynolds (though others say it was Col. John R. van Hoff) pushed for the Caduceus, and after being rejected by Surgeon General G.W. Steinberg, it was accepted by his successor Surgeon General W.H. Forwood in 1902. It’s pretty clear that Reynolds was confused, though, because he referred to the Caduceus as the Rod of Asclepius in correspondence with both men.

The mistake was noticed. Naturally, in 1917, it was the librarian to the Surgeon General who publicly called out this boohockus. There was a big debate in 1924 in The Military Surgeon about whether or not to switch symbols. Many agreed to switch to the Rod of Asclepius, but one said the Caduceus made sense because of its “ancient use in designating neutrality amongst noncombatants.” Again, I don’t really buy this. Anyway, the Corps kept the Caduceus, and many other medical organizations in the early 1900s also adopted it. This even included the American Medical Association in 1910, though they later corrected it to the Rod of Asclepius.

Today, this leads to some oddities, such as the fact the US Army Medical Corps uses the Caduceus, but the US Army Medical Department Center and School uses the Rod of Asclepius.


Anyway, back to the Rod of Asclepius to close out. Where does this whole snake thing come from in the first place? The most popular story is that ya boi Asclepius was going to examine a dude who just got killed by a Zeus lightning bolt. Asclepius got startled by a nearby snake, and killed it. But, a second snake comes in to be the hero and apparently stuffed some “herbs” into the dead snake’s mouth and brought it back to life. This then inspired Asclepius to do the same, and he revived the guy killed by lightning. As a shoutout to the OG snake healer, he adopted the coiled snake around the staff as his own emblem.

Another theory is that the Rod symbol was inspired by the story of Moses, who was commanded by God to create a brass serpent on a pole. When people were bitten by a snake, they could look at the pole and be cured.

Whatever the origin, it’s pretty impressive that the symbol has survived for so long, considering we still have it after the era when symbols of Greek gods were forbidden by the Catholic Church. The symbol re-emerged during Renaissance artwork (shoutout to resident new art connoisseur Brian Dorsey). Moreover, it’s a bit confusing how an animal traditionally associated with vices and the fall of Man came to symbolize the art of healing. However, historians argue that the snake, especially with its practice of skin shedding, also symbolizes rejuvenation and resurrection — nice complements to medicine.

In the end, my boy Stuart here best summarizes my thoughts on the Rod of Asclepius vs. the Caduceus:

“As god of the high-road and the market-place Hermes was perhaps above all else the patron of commerce and the fat purse: as a corollary, he was the special protector of the traveling salesman. As spokesman for the gods, he not only brought peace on earth (occasionally even the peace of death), but his silver-tongued eloquence could always make the worse appear the better cause. From this latter point of view, would not his symbol be suitable for certain Congressmen, all medical quacks, book agents and purveyors of vacuum cleaners, rather than for the straight-thinking, straight-speaking therapeutist? As conductor of the dead to their subterranean abode, his emblem would seem more appropriate on a hearse than on a physician’s car.” — Stuart L. Tyson, “The Caduceus”, in The Scientific Monthly

Just FYI, here’s the Stanford Med logo:



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