Pythagorean cup

A type of drinking cup that spills its contents if filled beyond a certain point

Pythagorean cup

A Pythagorean cup is a type of drinking vessel that is designed to function as a practical joke or a lesson in moderation. It is attributed to the ancient Greek philosopher Pythagoras, who is said to have invented it to teach his students about the dangers of greed and excess.

Cross-section of a Pythagorean cup

Design and Function

The Pythagorean cup appears to be an ordinary drinking cup, but it has a hidden mechanism that causes it to spill its contents if filled beyond a certain level. The cup contains a central column with a small hole at the bottom, which is connected to a siphon. When the liquid in the cup rises above the level of the siphon, the liquid begins to flow through the siphon and out of the bottom of the cup, emptying the entire contents.

The design of the Pythagorean cup is based on the principle of a siphon, which is a tube that allows liquid to flow from a higher elevation to a lower elevation, driven by the force of gravity. The siphon in the Pythagorean cup is cleverly concealed within the structure of the cup, making it appear to be a normal drinking vessel until it is overfilled.

Historical Context

The Pythagorean cup is often associated with the teachings of Pythagoras, who was known for his philosophical and mathematical contributions. Pythagoras and his followers, the Pythagoreans, believed in living a life of moderation and balance. The cup serves as a metaphor for these beliefs, illustrating the consequences of excess and the importance of self-control.

Diagram of a Pythagorean cup

Cultural Significance

The Pythagorean cup is sometimes referred to as a "greedy cup" or "Tantalus cup," named after the mythological figure Tantalus, who was punished by the gods for his hubris and greed. The cup is used as a teaching tool to demonstrate the principles of hydrodynamics and the concept of a siphon, as well as a moral lesson about the dangers of overindulgence.

In modern times, Pythagorean cups are often sold as novelty items or educational tools. They are popular souvenirs in regions with historical connections to ancient Greece, such as the island of Crete.

Pythagorean cups sold in Crete

Related pages

• Pythagoras
• Siphon
• Hydrodynamics
• Tantalus