Modern numerology reduces eighty-nine to eight and reads it as a number of material power and completion, the eight approached through an eight of the tens and a nine of fulfilment. This reductive reading is the whole of the number's symbolic content beyond its Fibonacci form. Eighty-nine is best described as a prime whose whole interest lies in its place in the Fibonacci sequence rather than in any body of tradition.
A separate and older-claimed system, generally called Chaldean numerology, assigns letters to digits irregularly rather than in Balliett's repeating one-to-nine sequence, and deliberately omits nine from the chart as too sacred to attach to an ordinary letter; its popular billing as a genuinely ancient Babylonian system rests on assertion rather than on any textual evidence that has been traced back that far.
Florence Campbell, a student of Balliett's, restated and extended the chart in Your Days Are Numbered in 1931, and Juno Jordan, founder of the California Institute of Numerical Research, standardised the modern four-part chart of life path, expression, soul urge and personality numbers in 1965; both writers worked from name and birth date rather than from any older number philosophy.