Numerology reduces a name or a date to a single digit, or occasionally to one of a small set of double digit "master numbers", by adding a letter or number value table against it until one figure remains. Which table is used, and what the resulting number is then read against, varies by system and by tradition.

History

The genuinely ancient layer of this practice is gematria, the Hebrew system that assigns each letter of the alphabet a fixed numeric value and reads meaning into words or phrases that sum to the same total. It is old and well attested, used throughout rabbinic literature to draw connections between scripturally significant words, and it became a central working tool of later Jewish Kabbalah, where a numeric match between two words is read as a real hidden connection between the things they name. Greek carried a close counterpart, isopsephy, the same letter to number practice applied to the Greek alphabet, attested in surviving graffiti and epigrams from antiquity and almost certainly behind the New Testament's "number of the beast", 666, in Revelation 13:18, itself widely read as an isopsephic encoding of a name.

The two systems this report item calls Pythagorean and Chaldean sit on shakier historical ground, and are named honestly here rather than smoothed into the same lineage as gematria. Pythagoras and his early followers held, on good ancient authority, that number underlies the structure of reality; but the specific letter to number table sold today as "Pythagorean numerology", a simple sequential count from A to Z, is not attested in any surviving text from Pythagoras or his school, and its documented use traces only to twentieth century esoteric writers who adopted his name for their own system. The "Chaldean" system likewise claims descent from ancient Babylonian priest-scholars, called Chaldeans by later Greek and Roman writers; no source in this atlas's catalog substantiates that claimed lineage, so it is recorded here as a claim rather than as settled history.

Four Systems

• Pythagorean, a sequential A to Z letter count, the most common system in present day Western numerology.
• Chaldean, a different, non sequential letter to number assignment, its claimed ancient Babylonian origin unverified.
• Hebrew Gematria, the ancient and well attested Jewish system, central to rabbinic exegesis and Kabbalah.
• Greek Isopsephy, the Hellenistic counterpart to gematria, attested in antiquity independent of Jewish practice.

The Digits

A reduction ordinarily ends at one of the digits one through nine, each carrying its own settled numerological character; most systems also stop early for three "master numbers", eleven, twenty two and thirty three, read as carrying an amplified version of their reduced digit (two, four and six respectively) rather than reducing them further.

How A Reading Is Constructed

A reading derives the numbers behind a name and a birth date using the letter and number tables above, then reads each resulting digit against the planet, the sephirah and the tarot key esoteric numerology conventionally pairs it with, the same correspondence chain the Kabbalah report item's Tree of Life and the Tarot report item's twenty two keys already carry on their own pages. Where the underlying claim of ancient origin is itself unsettled, as with the Chaldean system, the reading names the system by its common label without asserting a lineage this atlas cannot verify.

Where To Read More

• PythagoreanPythagorean: a sequential A to Z letter count, the most common present day system; the specific table is not attested in any surviving Pythagorean text.
• ChaldeanChaldean: a different letter to number assignment; its claimed ancient Babylonian origin is unverified against this atlas's source catalog.
• Hebrew GematriaHebrew Gematria: the ancient, well attested Jewish letter to number system, central to rabbinic exegesis and later Kabbalah.
• Greek IsopsephyGreek Isopsephy: the Hellenistic counterpart to gematria, attested independently in antiquity.
• 11, the digit a reduction ends on.
• 22.
• 33.
• 44.
• 55.
• 66.
• 77.
• 88.
• 99, the last digit before a reduction stops.
• 1111, a master number, read as an amplified 2 rather than reduced further.
• 2222, a master number, read as an amplified 4.
• 3333, a master number, read as an amplified 6.