Letters as Numbers: Isopsephy

Because classical Greek used its own alphabet for ordinary counting rather than adopting a separate numeral system, every Greek letter carries a fixed numeric value, Alpha through Omega running 1 to 800 among the twenty-four letters still spoken in the classical period, with three older letters no longer in ordinary use, digamma, koppa and sampi, retained purely to complete the numeral series up to 900. This dual role, the same symbol serving as both a sound and a number, is the foundation isopsephy builds on: summing a word or name's letters to find a total number and reading significance into two words or phrases that share the same sum.

Isopsephy runs in close historical parallel to Hebrew gematria, performing an identical operation on a different alphabet within a separate cultural and religious tradition, and both are considerably older than the modern Pythagorean and Chaldean numerology systems built centuries later on the Latin alphabet, which had to invent an artificial value assignment from nothing because Latin, unlike Greek and Hebrew, was never itself used as a numeral system in antiquity.