Two positions in every cycle · 阴阳
Yin and Yang: the polarity coordinate
Polarity is the alternating half of a stem or branch identity. It does not replace the five phases: Wood, Fire, Earth, Metal and Water each appear once as Yang and once as Yin.
A coordinate, not a score
Two alternating positions
A stem needs both its phase and its polarity to be identified. The same is true of a branch inside the sixty-year cycle: polarity tells you which alternating position it occupies.
01 · first in each phase pair
Yang
Yang stems occupy positions 1, 3, 5, 7 and 9 in the ten-stem sequence: 甲, 丙, 戊, 庚 and 壬. Yang branches occupy the odd-numbered positions in the twelve-branch sequence.
02 · second in each phase pair
Yin
Yin stems occupy positions 2, 4, 6, 8 and 10: 乙, 丁, 己, 辛 and 癸. Yin branches occupy the even-numbered positions. The sequence continues by alternating back to Yang.
Five phase pairs · ten stems
Every phase has a Yang and a Yin stem
The phase stays the same across each row. The polarity changes, so the written stem changes with it.
The twelve-branch rhythm
The branches alternate too
子 Rat begins at Yang, 丑 Ox follows at Yin, and the pattern repeats through all twelve branches. In the sixty-year sequence, a stem is paired only with a branch of the same polarity.
- 01子RatYang
- 02丑OxYin
- 03寅TigerYang
- 04卯RabbitYin
- 05辰DragonYang
- 06巳SnakeYin
- 07午HorseYang
- 08未GoatYin
- 09申MonkeyYang
- 10酉RoosterYin
- 11戌DogYang
- 12亥PigYin
This matching-polarity rule is why ten stems and twelve branches meet in 60 valid pairs rather than all 120 possible combinations. Follow the complete sixty-year cycle →
Where polarity changes the name
Ten Gods come in five polarity pairs
First compare the target stem's phase with the Day Master. That selects one row. Then ask whether their polarities are the same or different; that selects one of the two names in the row.
Open the complete Ten Gods reference →A worked stem relationship
Yin Earth Day Master, Yang Fire target
Fire generates Earth. Because the two stems have different polarities, the resource pair resolves to Direct Resource.
Yin Earth
- 01
Compare phasesFire generates Earth, so the target generates the Day Master.
- 02
Compare polarityYang and Yin are different polarities.
Yang Fire
zhèng yìn
What the coordinate establishes
Polarity is not a ranking
Yin and Yang distinguish alternating positions within the same system. Neither polarity is automatically better, stronger or more favourable than the other.
The labels also do not assign a person's gender or a complete personality. In a Four Pillars chart they identify stems and branches, and they help name relationships between those coordinates.