Dating from as early as 2800 BC the legend of Luo Shu or "scroll of the river Luo" tells of a huge flood in ancient China. One particular river that was flooding was the Luo River. The people tried to offer some sacrifice to the river's god to calm his anger. A tortoise then emerged from the water with a curious pattern. On its shell was a pattern of dots arranged in a three-by-three grid, such that the sum of the numbers in each row, column and diagonal all amounted to the number 15. This pattern, in a certain way, was then used to control the river by the Emperor Yu.

This grid of 9 numbers in its basic form is also known as the Magic Square. It has been found in Kabalistic text referring to the planet Saturn and also in western magic, the number 15 in numerology is the number of magic. The square itself is made up of three numbers by three numbers. The number for Saturn incidentally is 3, so 3x3 = the 9 grid. If you add all the numbers 1+2+3+4+5+6+7+8+9 together they equal 45. Then if you divide 45 by Saturn's number 3 it equals 15. The number 15 is the number of days it takes for the moon to wax and wane so indicating a correlation with the changes of Qi. This number is also equal to the 15 days in each of the 24 cycles of the Chinese solar year.

This Luo Shu square forms the basis of most Feng Shui formula. It provides the key to unlocking many of the secrets of the Ba Gua as the numbers correlate with the eight trigrams of the Later Heaven Ba Gua and its numerological path is used in flying star formula.