I’ve started bookmarking the interesting Wikipedia articles I stumble on. You’ll see them pop up here with the prefix “SILO”: “Stuff I Learned Online”. Enjoy the tidbits.


What’s the deal with medical organizations and snakes on sticks? Why is it sometime one snake and sometimes two snakes?

Rod of Asclepius

The Rod of Asclepius is a wooden rod with a single snake entwined around it. It’s a common symbol for medicine, used by entities such as the World Health Organization. Asclepius was the Greek god of medicine, son of Apollo. Why did he carry a snake on a stick? Some think it was symbolic; for example, the way snakes shed their skin could symbolize rejuvenation.

Possibly related (although there’s no way to know), the Rod of Asclepius resembles the rod with a bronze serpent1 that God told Moses to erect in the wilderness. Israelites bitten by poisonous snakes could be healed by just looking at the bronze snake. Fifteen-hundred years later, Jesus said that the snake was a picture of himself:

And as Moses lifted up the serpent in the wilderness, even so must the Son of man be lifted up. John 3:14
And I, if I be lifted up from the earth, will draw all men unto me. John 12:32

Caduceus

The caduceus is a rod with two snakes wrapped around the rod and each other. It was given to Hermes2, god of commerce and the messenger of the gods, by Apollo3, the father of Asclepius. Why did he carry snakes on a stick? The world is full of mysteries. The caduceus is also used by some modern organizations as a symbol of medicine, although the Rod of Asclepius is more common.

So why is the caduceus used as a medical symbol when it had no connection to medicine originally? Apparently in the late 1800’s the US military confused the two and started using the caduceus as a medical insignia. Oops.

I keep them straight in my mind by remembering that “caduceus” has a “deuce” in the middle, and it’s the one with two snakes.


  1. The brass serpent was later called “Nehushtan”.
  2. Mercury is the Roman god that corresponded to the Greek god Hermes.
  3. The god Apollo was called “Apollo” in both Greek and Roman pantheons.