Every student of Chaldean numerology should be familiar with key modern Chaldean numerologists such as Sepharial, Isidore Kozminsky, Cheiro, Pandit Sethuraman, Richard Cavendish, Gerun Moore, Lloyd Strayhorn, and Linda Goodman. All of these numerologists were also astrologers.

Sepharial (Walter Gorn Old) played a crucial role in transitioning from the older Chaldean school of “Kabbalistic astrologers” to modern numerology. He also introduced classical descriptions of numbers from Kabbalistic astrology, where the highest number described in this approach is 71. He later wrote a very popular book, “Kabala of Numbers” (1911).

In his development, he initially used an external method of alphanumeric coding of the Latin alphabet (C = 2, H = 8, X = 6). Later, he tested several different alphanumeric approaches but ultimately decided on phonetic numerology.

Isidore Kozminsky, like Sepharial, experimented with various methods of alphanumeric coding. At the latest, in an updated edition of “Numbers: Their Meaning and Magic” in 1911, he was the first modern numerologist to predict that we should, in some cases, treat the letter H as 5.  He also assigned the number 5 to the letter X. Like Sepharial, he described all the numbers he believed to have a “distinct potency of its own.” All other numbers he reduced to a number with such potency. His approach of dealing with name numbers is now considered outdated.

Cheiro (William John Warner) is regarded as the father of modern Chaldean numerology. He wrote several books covering numerology, with the most famous being “Cheiro’s Book of Numbers” (1926), where he advocated for the value of 3 for the letter C, 5 for the letter H, and 5 for the letter X.

He emphasized the importance of the Birth number (the day of the month one is born) and its connection to the Name number (that is, Total Name Number, aka TNN). He was one of the first to focus on the compatibility of numbers. He adopted Sepharial’s number descriptions, sometimes expanding them, so they corresponded to some very old descriptions. However, he described numbers only up to 52. He also wrote a book called “You and Your Star”, where he described the most suitable numbers for each day of the year based on astrological techniques.

Pandit Sethuraman, in his book “Science of Fortune” (1954), adopted Cheiro’s alphanumeric coding but summed the unreduced numbers of the first and last names. He also deviated from Cheiro’s views on number compatibility. Sethuraman expanded Cheiro’s descriptions based on his own insights and described numbers up to 108. Unlike Cheiro, he considered numbers 39 and 48 to be unfavorable.

Richard Cavendish, in his 1967 book “The Black Arts” (which has quite an inappropriate book title, especially in connection to astrology and numerology), introduced the classical internal method of alphanumeric coding (with C = 3, H = 8, X = 6), although he seems to have arrived at this through his own research. He emphasizes the importance of considering the numbers of vowels and consonants, a concept long neglected in Chaldean numerology.

Gerun Moore wrote a book in 1973 titled “Number Will Tell”. He adopted Cheiro’s alphanumeric coding system but made several changes and additions to the descriptions of numbers and the rules of compatibility. Notably, he described numbers 39 and 48 as the unlucky number 12.

He also rejected Cheiro’s model of favorable numbers for each day of the year. Instead, he created his own system, where each day of the year is generally assigned two suitable numbers (though in some cases, only one number is given). He labeled these numbers as “keys.” According to him, name numbers matching a person’s key numbers bring luck and harmony.

Lloyd Strayhorn wrote his book “Numbers and You: A Numerology Guide for Everyday Living” no later than 1980. He adopted Cheiro’s alphanumeric coding system. Although he prefers Chaldean numerology, he also considers Pythagorean numerology. Based on his research, Strayhorn introduced his own system of number compatibility, which differs somewhat from Cheiro’s model.

He also rejected Cheiro’s model of favorable numbers for each day of the year, offering instead his own astrological model with lucky numbers. He later published “Lloyd’s Numbers and You Relationship Guide: A Cosmic Blueprint to Happiness & Joy”, in which he distances himself significantly from older Chaldean approaches.

Linda Goodman published a book “Linda Goodman’s Star Signs” in 1987, which also introduces Chaldean numerology. She adopted Cheiro’s alphanumeric coding system and significantly enhanced the descriptions of numbers. However, her method of determining the TNN deviates from those of her predecessors.

Linda Goodman concludes the list of modern classics in Chaldean numerology. I believe that this list provides an appropriate foundation for studying contemporary Chaldean numerology.

There are also a few Chaldean numerologists who have uncritically incorporated Pythagorean methods of interpreting numbers and relationships. While some ideas from the Pythagorean system can be adopted, not all Pythagorean techniques are suitable for Chaldean numerology.