"Zi Wei Dou Shu" means "Purple Mild Calculation". As Zi Wei actually refers to the Emperor star, some other practitioners name it as Emperor Astrology. Zi Wei star is the first star of the series, and its position in your chart determines where all the other stars fall in the chart and hence this Chinese art of Astrology is named after Zi Wei.
Note that Zi Wei Dou Shu utilises the Chinese Lunar calendar instead of the solar calendar for its calculation of the Zi Wei Dou Shu charts. As like most Chinese Metaphysics studies, Zi Wei Dou Shu utilises the concept of palaces, stars, 5 Elements, Heavenly Stems, Earthly Branches and Luck Pillars to map out the charts.
The 12 palaces of Zi Wei Dou Shu (with their anglicised Han Yu Pin Yin pronunciation in brackets) are:
Life (Ming). This is your Self-Depicted palace. This palace indicates what you are in terms of characteristics. This is also the start of your first luck cycle.
Parents (Fu Mu). This sheds light on your parents' characteristics. This palace can also your appearance since we are a product of our parents.
Blessings (Fu De). This palace shows your emotional state, spirituality, motivation and noble help palace.
Property (Tian Zhai). This palace indicates the quality of the property you own or live in, including other immovable assets
Career (Guan Lu) This indicates the type of condition you will face at your place of work.
Servants (Pu Yi). Your luck with servants and friends would be depicted in this palace.
Traveling (Qian Yi). Your luck when travelling can be read off this palace.
Illness (Ji E). This palace gives an indication of the state of your health, including emotional health.
Wealth (Cai Bo). This palace sheds light on your ability to amass and store money.
Children (Zi Nv). Your offspring luck will be captured in this palace.
Spouse (Fu Qi). Your spouse luck will be captured in this palace.
Sibling (Xiong Di). You can assess your siblings' luck in this palace.
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