Greek numerals · Isopsephy
How did the Greeks write numbers with letters?
27 letters, 1 to 900
They gave each letter a value and added them up. Alpha to theta counted 1 to 9, iota to koppa 10 to 90, and rho to sampi 100 to 900, so 241 was ΣΜΑ, 200 + 40 + 1. That took 27 signs, so three old letters that had dropped out of writing were kept for 6, 90 and 900, and a small stroke told the reader a word was a number. Adding up the letters of an ordinary word is called isopsephy, and it is why Ἰησοῦς, Jesus, comes to 888.
͵ΒΚϚʹ
Or count a Greek word
888
The 27 signs
Units, tens, hundreds
The system probably started around Miletus in Ionia, which is why it is also called Ionic or Milesian. Finds now push it back to at least the 5th century BCE. Its first official use in Greece proper dates from about 200 BCE, and Athens, the last holdout, had fully switched by about 50 CE.
It is additive. Each rank has its own nine letters, so no letter is ever repeated and there is no zero: 606 is ΧϚ, 600 + 6. The 900 sign, sampi, sits at the very end, which historians take as proof that it had already stopped being used as a letter when the system was made. Koppa and stigma were kept the same way.
Past 9,999 the Greeks counted in myriads, units of ten thousand, written with an M. In that notation 1,234,567 is ρκγΜ͵δφξζ: 123 myriads plus 4,567.
How to read one
The marks that say “number”
A stroke at the top right, the keraia (ʹ), marks a numeral in modern Greek. Ancient and medieval manuscripts drew a line over the letters instead. A stroke at the bottom left (͵) multiplies the next letter by a thousand, so 2019 is ͵ΒΙΘʹ, 2,000 + 10 + 9.
Greek still uses them. In modern Greece letter numerals number kings, chapters and ordinals, the way English uses Roman numerals: Philip II of Macedon is Φίλιππος Βʹ. The 6 is often written as two letters, ΣΤʹ, with one keraia for the pair.
Fractions and zero. A number followed by a keraia could also mean one part of it: γʹ was one third and δʹ one fourth. The system has no zero, although astronomers working in base 60 used a round sign much like omicron for an empty place.
Before the letters: Attic numerals
An older system took its signs from the first letter of each number word: Ι for one, a Π shape for five (ΠΕΝΤΕ), Δ for ten (ΔΕΚΑ), Η for a hundred (ΗΕΚΑΤΟΝ), Χ for a thousand (ΧΙΛΙΟΙ) and Μ for ten thousand (ΜΥΡΙΟΙ). Signs repeat, like Roman numerals without subtraction: 2001 is ΧΧΙ and 1320 is ΧΗΗΗΔΔ. It was probably in use by the time of Solon in the 7th century BCE, turns up on Athenian inscriptions from 454 to 95 BCE, and was used most for sums of money.
Isopsephy
When a word became a sum
Because every word was also a string of numerals, any word had a total. Greeks called matching totals isopsephy, from isos, equal, and psephos, a pebble used for counting. It is the same practice as Hebrew gematria.
Love notes. A graffito at Pompeii, from around 79 CE, reads “I love her whose number is 545,” written φμε: 500 + 40 + 5.
Political jokes. Suetonius records a line passed around Rome after Nero had his mother killed: Νέρων ἰδίαν μητέρα ἀπέκτεινε, “Nero killed his own mother.” The Loeb edition’s note explains the joke: Nero’s name adds up to 1005, the same as the rest of the sentence. Try both in the counter above.
Revelation. The verse about the number of the beast tells the reader to “count” it with ψηφισάτω, the same pebble word. Medieval Greek manuscripts write 666 as χξϛ, 600 + 60 + 6. The page on why 666 is the number of the beast has the Hebrew reading.
888. Ἰησοῦς adds up to 888, and a Christian passage added to the Sibylline Oracles makes a riddle of it: “eight ones, and as many tens on these, And yet, eight hundred will reveal the name.” A Gnostic group, the Marcosians, built teachings on the same number. The bishop Irenaeus attacked them for “juggling with forms and numbers,” and the practice never became popular in Christianity.
Real vs legend
Greek numerals, sorted
| Claim | Status |
|---|---|
| The Greeks wrote numbers with the letters of the alphabet. | Real · 27 signs |
| Letter numerals were the Greeks’ first system. | Partly · Attic signs came first |
| Ἰησοῦς adds up to 888. | Real · 10 + 8 + 200 + 70 + 400 + 200 |
| 888 was standard Christian teaching. | No · a fringe practice, attacked by Irenaeus |
| Romans joked that Nero equals “killed his own mother.” | Real · both sides 1005 |
| Pythagoras invented isopsephy. | Unconfirmed · only a report via Aristotle |
| Words with equal totals share a hidden truth. | Legend · interpretation |
| Greeks still use letter numerals. | Real · Φίλιππος Βʹ |
Questions
Greek numerals
What are ancient Greek numerals?
There were two systems. The older Attic one used the first letters of number words: Ι for 1, a Π shape for 5, Δ for 10, Η for 100, Χ for 1,000 and Μ for 10,000. The alphabetic system that replaced it gave each of 27 letters a value from 1 to 900 and added them.
What are the Greek numbers 1 to 10?
Αʹ Βʹ Γʹ Δʹ Εʹ Ϛʹ Ζʹ Ηʹ Θʹ Ιʹ. The sign for 6 is stigma, Ϛ, which modern Greek often writes as ΣΤʹ. In lowercase they run αʹ to ιʹ.
What does isopsephy mean?
Adding up the number values of the letters in a word and comparing the total with other words. The name comes from the Greek isos, equal, and psephos, the pebble used for counting.
What is Greek gematria called?
Isopsephy. Gematria is the name for the same practice with the Hebrew alphabet.
Why is Jesus’s number 888?
Because the Greek letters of Ἰησοῦς add up to 888: iota 10, eta 8, sigma 200, omicron 70, upsilon 400 and sigma 200. A Christian passage in the Sibylline Oracles and the Gnostic Marcosians made a point of it.
What does ω mean in Greek?
Omega, the 24th and last letter. As a numeral it is 800. Its name means “big o,” to tell it apart from omicron, and it stands for the end, as in “the Alpha and the Omega.”
Sources
Where this comes from
- Greek numerals, values, dates, keraia, myriads, modern use: Wikipedia.
- J. J. O’Connor and E. F. Robertson, “Greek number systems,” MacTutor History of Mathematics, University of St Andrews: mathshistory.st-andrews.ac.uk.
- Attic numerals, signs, dates and examples: Wikipedia.
- Isopsephy, meaning, Pompeii graffito, Revelation’s “count”: Wikipedia.
- Suetonius, Life of Nero 39, Greek text and Loeb translation with notes (1914): LacusCurtius.
- The Sibylline Oracles, Book 1, translated by Milton S. Terry (1899): Wikisource.
- Irenaeus, Against Heresies I.15, on the Marcosians and 888: New Advent.
- Gematria, Greek use and its reception in Christianity: Wikipedia.
- Omega: Wikipedia.
- Unicode Character Database, Greek numeral signs: unicode.org.
Share
An image of your number in Greek letters. Copy link reopens it.
Poster
The 27 signs and their values, on one print.