The “cup of Pythagoras” or “fair cup” created by the Samian philosopher, mathematician, geometer and music theorist was intended to suggest and observe the measure, “metron ariston”.
The “fair cup”, which dates from around the 6th century BC, is a masterpiece of the hydraulic technology of the ancient Greeks, but also a teaching tool. In addition to limiting the consumption of wine through a “smart glass”, Pythagoras wanted to teach his students moderation and temperance. When moderation is exceeded, “hubris” occurs, which results in punishment, “tisis”. All men ought to enjoy in moderation what is provided for them without eagerly seeking more.
How it works: There is a line engraved on the inside, which defines the quantity of wine. If the user does not exceed the line, then he can enjoy his “drink”. However, it only takes one more drop to go over the line and then the cup will empty, spilling all the wine from its base.
Its mechanism: In the center of the cup there is a column that is placed over a tube that leads to the bottom of the cup. As the cup fills up, the wine level inside the central column also rises. As long as the liquid does not rise above the demarcated line, there is no problem. However, as soon as the liquid exceeds the line, the particles are drawn into each other, resulting in the emptying of the cup. Pythagoras’ construction follows the law developed by Pascal centuries later for communicating vessels