In short
- Pythagorean numerology values the letters 1 to 9 in alphabetical order, repeating. Chaldean values them 1 to 8 by sound, and no letter is a 9.
- Pythagorean uses the full name on your birth certificate. Chaldean uses the name you actually go by.
- Chaldean also reads the two-digit total before reducing it, so 35 and 44 mean different things.
- Neither is ancient in its modern form: Pythagorean was assembled in America around 1900, Chaldean was popularized by Cheiro in the 1920s.
- This site uses the Pythagorean system for every calculation, so the same name gives the same number on every page.
Two charts, two answers
Take a name and work out its expression number twice. On the Pythagorean chart, Sarah Jane Wilson comes to 1 + 1 + 9 + 1 + 8 + 1 + 1 + 5 + 5 + 5 + 9 + 3 + 1 + 6 + 5 = 61 → 7. On the Chaldean chart the same letters come to 3 + 1 + 2 + 1 + 5 + 1 + 1 + 5 + 5 + 6 + 1 + 3 + 3 + 7 + 5 = 49 → 13 → 4. One system says the name is a 7, the thinker.
The other says it is a 4, the builder. Both cannot be right, and the honest answer is that neither is a measurement. They are two conventions, and the useful thing is to know which one you are using.
Occasionally the two agree. Mary Louise Carter, the example name used in the guides on this site, is a 5 on both charts (77 → 5 and 50 → 5). That is coincidence, and anyone who has run a few names through both will have seen how rarely it happens.
How the Pythagorean system values letters
The Pythagorean chart is the one in almost every modern book: the letters are numbered 1 to 9 in alphabetical order, and the sequence starts again at J and again at S. A, J and S are 1. B, K and T are 2. C, L and U are 3.
D, M and V are 4. E, N and W are 5. F, O and X are 6. G, P and Y are 7.
H, Q and Z are 8. I and R are 9. Every letter has a value and nine letters’ worth of the alphabet share each number.
From the chart, the system builds the name numbers this site explains in its guides: the expression number from every letter, the soul urge from the vowels, the personality number from the consonants. It uses the full name on the birth certificate, reduces totals to a single digit, and keeps 11, 22 and 33 as master numbers.
How the Chaldean system values letters
The Chaldean chart is built on sound rather than alphabetical order, and it runs from 1 to 8. A, I, J, Q and Y are 1. B, K and R are 2. C, G, L and S are 3. D, M and T are 4.
E, H, N and X are 5. U, V and W are 6. O and Z are 7. F and P are 8. No letter is a 9, because the system treats 9 as sacred and keeps it out of the alphabet, though a total can still reduce to 9.
Three other rules separate it from the Pythagorean system. Chaldean practitioners use the name a person actually goes by, nickname and all, on the argument that the name in use is the one that shapes a life, and they recalculate when a name changes. They read the two-digit compound number before it is reduced, so that a name totaling 35 and a name totaling 44 are read differently even though both come down to 8. Cheiro’s book gives a meaning for every compound from 10 to 52. And they generally do not divide the name into vowels and consonants as the Pythagorean system does.
Where each system comes from
The Pythagorean system is American and about 120 years old. Mrs L. Dow Balliett, a music teacher who lived in Atlantic City, self-published a series of books from 1905, beginning with How to Attain Success Through the Strength of Vibration. They set out the alphabet-to-number chart and the idea that a name and a birth date could be read.
Her friend Julia Seton is credited with giving the practice the name numerology, and Juno Jordan’s Numerology: The Romance in Your Name, published in 1965, fixed the system most writers have used since. The name Pythagorean is a tribute to the Greek school’s belief that number underlies everything. No numerology manual from Pythagoras exists.
The Chaldean system claims descent from the Chaldeans of ancient Babylon. The claim is hard to examine, because the earliest documented forms of the modern chart are in two British books of the same era. Sepharial’s The Kabala of Numbers (Walter Gorn Old, 1911 and 1913) and Cheiro’s Book of Numbers (William John Warner, 1926), which is the one most Chaldean practitioners still follow. Whether either author had access to anything Babylonian is unproven. What is certain is that the system as practiced today dates from the same few decades as the Pythagorean one.
Which one to use
Use one, consistently, and know which. The practical argument for the Pythagorean system is that it is what nearly everyone else uses, so your numbers are comparable with the books, the calculators and the other people in the room. The argument its practitioners make for the Chaldean system is that its sound-based values are more deliberate and its compound numbers more detailed. There is no evidence that either predicts anything, and this site says so in its article on whether numerology is real.
Sign of Nine uses the Pythagorean system for every calculation, and the editorial approach sets out the exact rules. Name numbers use the full birth name. The life path reduces day, month and year separately. Master numbers are kept where they appear, and 44 and above are reduced. The point of a single system is that a name or a date gives the same number on every page, which is the minimum a reader should be able to expect.