The Pythagorean Cup (also known as the Pythagoras Cup) is one of Pythagoras’s lesser-known inventions. Depending on who you speak to, this rather plain looking cup was either meant to teach people a lesson in moderation or demonstrate the philosopher’s sense of humor.
Local traditions in Samos, Greece, claim that Pythagoras crafted the cup to inspire people to drink wine in moderation. Inside the cup there is a line that defines the maximum level of wine the cup can hold. A trickle above that line and the cup automatically empties its contents from a hidden hole in its base.
This artifact is also known as the “Cup of Justice” or “Greedy Cup,” since many scholars believe that Pythagoras—who apparently wasn’t much of a drinker—wanted to show his students and followers the detrimental effects of greediness in one’s life.
To better understand how it works, it helps to see a cross-section of a Pythagorean Cup. This allows you to view the hidden channel that snakes through the central column of the vessel. If a person stops filling the cup before it passes the top of that column, they can enjoy their beverage without issue. However, if the person becomes greedy for more and fills the cup beyond this height, the pressure of the liquid builds up in the channel and then gravity takes over. The siphoning effect causes the liquid to spill out through the bottom of the cup, leaving the eager drinker wet and thirstier than before – their cup emptied by their own greed.
A cross-section of a Pythagorean cup when filled with wine. (Nevit Dilmen / CC BY-SA 3.0 DEED)
Find out how this curious artifact employed basic principles of gravity and atmospheric pressure to teach the concept of moderation in the Artifact World article ‘Pythagorean Cup: Turning Greedy Partygoers into Wet Blankets’ available in the May – June 2024 50th Issue Special Edition of Ancient Origins Magazine. Get it here!
This article first appeared in the 39th issue of Ancient Origins Magazine and was the 2023 winner for Storytelling: Short Piece at the European Publishing Awards.
Feature image: Pythagorean cup isolated on white background. Source Юлия Серова / Adobe Stock
By Alicia McDermott