3 Mother Letters: Aleph - Mem - Shin
3 - mother letters - ש מ א Aleph, Mem, Schin Air - Water - Fire Sulphur, Mercury, Salt
THREE MOTHER LETTERS: ALEPH ( א ) Air MEM ( מם ) Water SHIN ( ש ) Fire
7 Double Letters
The seven double letters have both the soft and a hard way of pronouncing them, reflecting their dual nature. The positive and negative, the yin and yang…
SEVEN DOUBLE LETTERS: BET ( ב ) Saturn GIMEL ( ג ) Jupiter DALET ( ד ) Mars KAF ( כ ) Sol PEY ( פ ) Venus RESH ( ר ) Mercury TAV ( ת ) Luna
12: Twelve Simple Letters
Pythagoras, as one example among many, believed that the number 12 was the number of the universe, insofar as "the universe" is understood as the yoking of the 1 (God) to the 2 (creation-- the variegated expression of the 1). You find a similar concept in the I Ching, where the first two hexagrams are related to the yang (1) and the yin (2).
TWELVE SIMPLE LETTERS: HEY ( ה ) Aries VAV ( ו ) Taurus ZAYIN ( ז ) Gemini CHET ( ח ) Cancer THET ( ט ) Leo YOD ( י ) Virgo LAMED ( ל ) Libra NUN ( נ ) Scorpio SAMEK ( ס ) Sagittarius AYIN ( ע ) Capricorn TZADI ( צ ) Aquarius QUF ( ק ) Pieces