The Rod of Asclepius vs the Caduceus

Often confused, the one without wings is the medical symbol.

the Rod of Asclepius

The Greek god Asclepius was the son of Apollo and became the god of healing/medicine. There are a host of legends about his medical powers – from his ability to heal the sick to his learning how to resurrect the dead. The most recognizable element of the Asclepius story though is his serpent-entwined staff.

The Rod of Asclepius is a wooden staff with a single snake coiled around it. Like Asclepius himself, there isn’t one consistent story explaining the snake. In one version a snake taught Asclepius the secrets of medicine, in another he watched one snake use herbs to revive another snake, etc. Over time the Greek association of medicine with snakes became intertwined (not unlike the Rod of Asclepius). Temples to Asclepius served as centers of healing, and given his association with snakes, non-venomous snakes were welcome. Snakes would crawl over patients’ beds and had free-reign of the buildings – Indiana Jones’ worst nightmare.

Over the millennia the Rod of Asclepius became an international symbol of healing & medicine. You can find it in the logo of the World Health Organization, a whole host of national medical associations, and on the side of ambulances everywhere … unless someone has accidentally used the caduceus instead.

The Caduceus

From the son of Apollo to the brother of Apollo, Hermes was the Greek messenger god who moved between worlds. After generously giving Apollo his tortoise shell lyre, Apollo returned the favor by gifting Hermes his wand / staff. This wand is known as the caduceus which has two snakes entwined around the wand with a set of wings at the top.

The image of a double snake wand is not unique to the Greeks. The caduceus has origins in ancient Mesopotamia going back to at least 3,000 BCE. Hermes isn’t even the only Greek messenger god to carry one – the goddess Iris also carries a caduceus. Like the Rod of Asclepius, there isn’t just one Greek explanation for the origin or meaning of the wand. One story says that Hermes saw two snakes fighting and he used his wand to break up the fight (and they became entwined around the wand). From this the caduceus has come to represent peace but it also represents trade as Hermes was the god of (among other things) commerce, cunning, and thieves. One thing it does not represent is medicine.

The Confusion

One reason for the confusion between these two symbols is they (more or less) look similar. Further, there is nothing about the Rod of Asclepius that looks particularly medical so it’s easy to forget which is which.

One of the biggest sources of confusion in the United States is the Army Medical Department (AMEDD). For some branch insignias the AMEDD uses the Rod of Asclepius but for others it uses the Caduceus (despite the caduceus having nothing to do with medicine). The Army mistakenly used the caduceus in 1851 and the mistake spread to other branches. At this point they are well aware they’re using the wrong symbol but won’t change.

Today it’s not uncommon to find the caduceus mistakenly on the labels of products that want to look more authoritatively medical, purely as a marketing tactic. Maybe using the symbol for commerce as a manipulative way to generate sales isn’t entirely a mistake.

Added info: perhaps at some point in the future the confusion will be sorted out but, if Starfleet Medical is any indication, the problem will persist until at least the 22nd century.

Pareidolia and Who Is In The Moon

A man’s face, a rabbit – different cultures see different things because humans are hardwired to look for patterns.

Over thousands of years of evolution our brains are hardwired to find patterns. For example, finding the pattern of tiger stripes in the tall grass is a pretty valuable skill to have. We use pattern recognition for defense, for finding information, for reading faces, etc. As our brains are constantly searching for patterns we’re bound to get it wrong sometimes and find meaning in things where there is none.

Pareidolia is when we incorrectly recognize something where there is really nothing. This can be auditory, such as “hearing” a word in what’s really just random sounds or white noise, but most of the time pareidolia is visual. We “see” animals in clouds, we “see” butterflies in Rorschach inkblot tests, etc. Facial pareidolia is when we see faces in things such as electrical outlets, the front of cars, burnt grilled cheese sandwiches, or even on the surface of the moon.

Who is on the Moon?

The surface of the moon is marked by impact craters from asteroids as well as large craters of solidified ancient lava. In the same way ancient humans connected the stars to create constellations, people have looked at these lunar markings and “seen” a variety of things.

The Man in the Moon

A European tradition going back to at least the 14th century finds the whole body of a man carrying sticks on the surface of the moon. While stories vary, he’s said to be a man caught gathering sticks on a Sunday. As punishment for breaking the Sabbath he was banished to the moon.

The Haida of the Pacific Northwest North America see this shape as a boy (instead of a man) who had been gathering firewood by moonlight. The boy insulted the moon and was similarly banished to the moon as punishment.

Other traditions see just the face of a man and not the whole body. Some say the man is Caine from the Bible, also sent to the moon as punishment. Talmudic folk tradition says this person is Jacob.


Jack & Jill

The nursery rhyme of Jack & Jill is based on the Scandinavian myth of Hjuki and Bila. The two children were said to be carrying a pail of water when the moon god Mani carried them to the moon (where they can be seen carrying their pail).


The Woman in the Moon

Sometimes the man/boy carrying sticks on the moon is said to be a woman (a witch of course) carrying sticks. In the southern hemisphere however, where the moon is seen upside down (depending on your cultural point of view), the Māori of New Zealand see a different shape as a woman. Rona was carrying water at night but tripped when there was insufficient moonlight to light her way. Hurt and angry she cursed the moon. The moon heard her insults and (like the punishment in the Haida legend) she’s now on the surface of the moon along with her water jug.

The Samoans say this woman is Sina, who thought the moon looked like a giant breadfruit and asked the moon to come down to let her child have a bite. The moon, insulted by this, took Sina, the tools she was working with, and her child back to the moon.


A Pair of Hands

In some Hindu traditions the hands of Astangi Mata are seen on the surface on the moon.


Name of Ali

In Islam, where there is a history of aniconism and not depicting sentient beings in art, there is a Shiʿite tradition of seeing the name of Ali (the son-in-law of Muhammad) written on the surface of the moon.


A Rabbit

In India the Buddhist Jātaka tales have a story of a rabbit that sacrifices itself by jumping into a fire. The rabbit is saved and placed on the surface of the moon. In China the rabbit Yutu is seen on the moon preparing the elixir of life in a bowl. The Japanese also see a rabbit with a bowl but instead of a magical elixir it’s preparing rice cakes.

Mesoamerican groups also see a rabbit on the moon. As the one story goes Techuciztecatl (the moon) was hit in the face with a rabbit, the imprint of which is still on the moon.


A Toad

The Selish people tell of a wolf who was romantically pursuing a toad in the moonlight. Just before being caught by the wolf the toad leaped so high she landed on the moon. Another toad on the moon is a variation of the Chinese rabbit on the moon story. In this version after the rabbit prepared the magical elixir for the Moon goddess Chang’e, the goddess drank the elixir and was transformed into a toad.

The Kimbundu tribe of Angola have the story of a prince who was only permitted to marry the daughter of the moon. Only a frog knew the way to get to the moon so he served as messenger between the Earth and the moon. Now the frog can be seen on the moon.


Thousands of years of humans have looked up at the moon from cultures around the world and have, through creativity and pareidolia, seen a variety of things. Cultures have explained these figures with creation myths or moral lessons, giving us the stories we know today.

Bonus: One of the most famous versions of the man in the moon is seen in the 1902 Georges Méliès film Le Voyage dans la Lune.

The Georges Méliès film Le Voyage dans la Lune (A Trip to the Moon) is a classic early film.

Germanic Gods (and Saturn)

In the English language the days of the week are named for six Germanic gods … and the Roman god Saturn.

In the Indo-European family tree of languages, English is a descendant of Germanic languages. English also inherited elements of ancient Germanic culture such as Germanic mythology. The Germanic peoples took the Roman idea of naming the days of the week for various gods, but they changed the Roman gods to Germanic gods (except one).

• Sunday is named after the Germanic goddess Sunna (aka Sól in Norse mythology). Along with her brother Máni, she was taken from their father Mundilfari and placed in the sky. Sunna is the sun, moving across the sky in her chariot. Her brother is the moon, moving across the sky in his chariot. To make sure they keep moving the gods set two wolves to chase each sibling continuously. The wolf Sköll chases Sunna. From her we get the Sun’s day, or Sunday.

Monday is named for the Germanic god Máni, brother of Sunna (as mentioned above). He rides through the sky on his chariot and is chased by the wolf Hati. From him we get Moon’s day, or Monday.

Tuesday is named for the one-armed Germanic god of war Týr (aka Tíw), which became Tīwes day or Tuesday.

• Wednesday is named for Odin (aka Wōden), the central god of the Germanic pantheon of gods. From him we got Wōdnes day which became Wednesday.

Thursday has perhaps the most well-known origin. Pop culture has made the hammer-wielding god of thunder & lightning Thor (aka Þunor – pronounced “Thunor”) one of the most well known Germanic gods. His name is also the origin for our word thunder which, in modern German, is “donner” and gives us Donnerstag or “Thunder day / Thursday.” In English Thor’s day became Thursday.

Friday is named for the Germanic goddess Frigg (aka Frīja, or Frea). She was the wife of Odin and, given a good deal of mythological overlap, she and the goddess Freyja may have been the same character at one point. Frigg’s day became Friday.

Saturday is the odd man out. In the West Germanic languages Saturday comes from the Latin “Saturni dies” or Saturn’s day, named for the Roman god Saturn. Around Scandinavia however, in Norse Germanic languages, Saturday is called by different variations of lørdag or laugardagur, which translates as Bath / Laundry Day.

Added info: The reindeer pair Donder & Blitzen from the Christmas story Rudolph the Red-Nosed Reindeer, come from the Germanic words for thunder & lightning.