Caduceus - The Symbol of Medicine?

            The staff on the left is the caduceus while the staff on the right is the staff of Aesculapius.  The staff of Aesculapius is the official symbol of medicine while the caduceus is often mistakenly used in this capacity.  I will attempt to clarify the confusion.

            Aesculapius is regarded as the "God of Medicine".  Hippocrates (460-377 BC), the "Father of Medicine" claimed direct descent from Aesculapius as a sign of superiority.  Ancient temples called Aesculapieions were constructed as centers for medicine.  It is his staff that medicine adopted as its symbol.  The myth behind his staff is as follows:  Aesculapius was examining a man that the god Zeus had just struck dead.  During the exam a snake entered the room, and Aesculapius promptly killed it.  A second snake then entered the room and placed herbs in the mouth of the first snake reviving it.  Aesculapius realized the lesson and placed the same herbs in the mouth of the man reviving him.  Aesculapius adopted the serpent coiling around a staff as his symbol.

            With the rise of the Catholic Church in the Middle Ages symbols and gods were suppressed.  Therefore, the urine flask (symbolizing the rising practice of uroscopy) replaced the staff of Aesculapius as the symbol of medicine.  Then, with another religious revolution during the Reformation, Catholic saints of medicine were no longer in favor.  Instead, the ancient symbols rose to prominence, and Aesculapius' staff was once again the symbol of medicine.

            The Caduceus on the other hand represents the magical rod of the Greek messenger-god Hermes (or Mercury).  It was his duty to lead the souls of the dead to the underworld.  Hermes was the god of thieves, wealth and commerce.  His staff had its origin when Hermes separated two fighting snakes, and they entwined themselves around the staff in friendship.

            Considering the role of Hermes as the leader of the dead and the god of wealth and thievery, it is inappropriate for his caduceus to be the symbol of medicine.  It is entirely appropriate, though, for the staff of Aesculapius to be its symbol.

            So, how did they become confused?  One theory states that John Churchill of London, a medical publisher, used a caduceus as his printer's mark on his books.  Many of his publications happened to be medical books.  Although it was not his intention to associate the caduceus with the medical profession others did not see the distinction.  United States publishers assumed that the caduceus was the symbol of medicine because of Churchill's use and began to display it on their medical texts.  The popularity of the caduceus spread when the assistant surgeon of the United States Army Medical Corps, Captain Frederick Reynolds, suggested it as a new symbol for their uniforms in 1902.  It was obvious that he did not know the difference between the two staffs.

The symbol of the US Army Medical Corps - the Caduceus.

References:

Williams, Nathan.  "Serpents, staffs and the emblems of medicine."  JAMA 281(5): 475.  3 Feb 1999.

Wilcox, Robert.  "The symbol of modern medicine: Why one snake is more than two."  Annals of Internal Medicine 138(8): 673-677.  15 April 2003.