The three major forms of numerology in use today are the Kabbalah, the Chaldean and the Pythagorean. I use aspects of all three when I prepare and interpret charts.

The Kabbalah ( which means knowledge that comes through the mind and soul rather than through a flesh and blood teacher) originated in Hebrew mysticism, and interprets only the meaning of the name. The Kabbalah was developed for the Hebrew alphabet, and therefore has only 22 vibrations ranging from 1 to 400. It was adapted for the Greek alphabet, then further adapted for the Roman alphabet.

Chaldean numerology was originally developed in Ancient Babylon (now Iraq), and combines Kabbalistic name interpretation with aspects of astrology. The 9 is considered holy and therefore is kept apart from other vibrations, except when it results as the sum of vibrations (e.g., from an individual's name). In Chaldean numerology, compound numbers always used. Single digits represent the outer aspects of a person, while double digits reveal inner influences.
 
 

The Pythagorean method was developed by Pythagoras, a Greek mathematician and metaphysician who lived during the 6th century BCE. He was most widely known for his proposition that the square of the hypotenuse of a right triangle is equal to the sum of the squares of the other two sides.

Pythagoras was as interested in metaphysics and spiritual development as he was in math, so it's no wonder he joined the two disciplines. He studied at the Hermetic (after Hermes, messenger of the gods) Wisdom Schools of the Egyptian holy city of Heliopolis (later named Alexandria) and incorporated many of the same teaching techniques with his own students in Greece. For example, his students had to memorize everything rather than write it down. This approach is still used for geometry students learning theorems.

The right triangle was Pythagoras' "Eureka" (which means "I found it"). The right triangle can also be used to symbolize the world of an individual and serves as the original basis for the numerological interpretation of the life pattern of an individual. Like the Chaldean method, Pythagorean numerology analyzes both name and date of birth, and the interaction between the two. The basic vibrations are 1 through 9, although the 11 (K) and 22 (V) are not reduced to a single digit because these are master vibrations.

Abracadabra is a less frequently used form of numerological interpretation. It is based on the subject's name, and uses a series of triangles to arrive at numerical values that provide information about character and events.

A New Kabbalah has also been developed for use with the modern Roman alphabet. It, too, is based on name, and relies on Pythagorean methods to determine time periods. The New Kabbalah is concerned more with events than character.