Isopsephy: the Greek game of names that share a number

In the Greek world the letters of the alphabet also served as numerals, according to the system known as Milesian or Ionic: alpha 1, beta 2, up to theta 9, then iota 10 and so on, with three archaic signs added to complete the series. Every word therefore had a numerical value. When two words gave the same sum they were said to be isopsephic, from isos, “equal”, and psephos, the pebble used for counting.

Graffiti and satire in the Roman world

The game was popular at every level. In Pompeii a graffito in Greek declares the writer's love for a woman “whose number is 545”, without revealing her name: a gallant way of concealing and alluding at the same time. The practice assumed that the reader knew the system and enjoyed searching for the right name among the possible ones.

The historian Suetonius, in his life of Nero, records a satirical verse that circulated in Rome after the killing of Agrippina. In Greek the name Nero and the phrase “killed his own mother” had the same value, 1005. The gravest accusation was thus entrusted to an equation, hard to punish because formally it was only a calculation.

The epigrams of Leonides of Alexandria

In literature isopsephy became a display of virtuosity. Leonides of Alexandria, a poet active in Rome in the time of Nero and Vespasian, composed epigrams in which the couplets had identical numerical sums. Some of these poems are preserved in the Palatine Anthology, the great Byzantine collection of short Greek poetry, and show how much arithmetical skill was prized as a poetic ornament and as a refined gift for the powerful.

Leonides presents this technique as his own novelty, and in several epigrams he offers his verses to the emperor or to women of the imperial family on festivals and birthdays. Those who have checked the calculations have found that in many cases the sums really do match: a sign of patient work on the choice of words, since the poet had to balance metre, meaning and arithmetic at the same time.

Divine numbers and religious controversy

In the first Christian centuries isopsephy entered theological debate. Irenaeus of Lyon, in his work Against Heresies written around 180, describes the calculations of the Gnostic teacher Marcus, who attributed mysterious meanings to the letters and their values. In the same circle it was noted that the Greek name of Jesus, Iesous, adds up to 888, a number also discussed in the verses of the Sibylline Oracles.

Even better known is the case of Abrasax, or Abraxas, the name of a heavenly power in the system of the Gnostic Basilides. According to Irenaeus, its letters add up to 365, the number of days in the year; Saint Jerome observed the same value for Meithras, a Greek spelling of the name Mithras. The name Abrasax appears on numerous engraved gems of the imperial age, often accompanied by composite figures.

Isopsephy reveals a constant feature of ancient culture: the conviction that language contained hidden orders. From the love graffito to political polemic and religious speculation, the same simple calculation could serve to play, to strike or to meditate. From this very tradition comes the most debated interpretation of all, that of the number of the Beast in the Revelation of John.