TL;DR: The Sibling line (Hào Huynh Đệ) carries the same element as the palace of the hexagram, symbolizing siblings, friends, colleagues, peers, and rivals. When asking about those people, it is the useful spirit; when asking about money, it is the adverse spirit because it controls the Wealth line (Thê Tài), which is why Tang San Buo Dich compares a Sibling line holding the Self line while seeking wealth to climbing a tree to catch fish. This must be distinguished from the Rob Wealth (Kiếp Tài) of Bát Tự: Bát Tự compares to the day stem, while Lục Hào compares to the element of the palace.
How Is the Sibling Line Determined?
The Sibling line (Hào Huynh Đệ) is the line whose five-element phase matches the element of the palace containing it. If the hexagram belongs to the Qian or Dui palace, the Sibling line is a Metal line; if it belongs to the Zhen or Xun palace, the Sibling line is a Wood line; if it belongs to the Kan palace, the Sibling line is a Water line; if it belongs to the Li palace, the Sibling line is a Fire line; if it belongs to the Kun or Gen palace, the Sibling line is an Earth line. This assignment belongs to the Six Relatives (Lục Thân) system of Lục Hào, formed in the time of Jing Fang and gradually refined through the Ming and Qing dynasties in works such as Tang San Buo Dich and Bốc Phệ Chính Tông.
It is called Sibling because this line shares the element of the palace, meaning it shares the same five-element "bloodline," just like siblings from the same parents. From there it is broadly assigned: blood siblings, friends, colleagues, peers, partners, and also competitors. The book Lục Nhâm, volume 1, discussing the Six Positions, gives a similar definition: Sibling means brothers and sisters; to divine about such people one must find the Sibling line and judge from it.
Because Sibling controls Wealth (Thê Tài, the line whose element is controlled by the palace element), in all questions involving money this line carries the meaning of loss, contention, and division of shares. This is the key point that makes Sibling both a useful spirit in some cases and an adverse spirit in others.
When Is Sibling the Useful Spirit?
According to Tang San Buo Dich by Master Dã Hạc, when divining about siblings, friends, co-workers, or peers, the Sibling line is the useful spirit. In this case, if Sibling is prosperous and supported by the Day Spirit or Month Command, or is generated and combined by a moving line, it is a good sign for the person asked about. Conversely, if Sibling is clashed and controlled, falls into Emptiness (Không Vong), or suffers Month Destruction, it is an unfavorable sign.
Also according to Tang San Buo Dich, when divining about children, the Offspring line (Tử Tôn) is the useful spirit, and because Sibling generates Offspring, in that case Sibling plays the role of original spirit, meaning a positively supporting line. The book Lục Nhâm, volume 1, also states clearly: divining about children greatly requires the Sibling line because it generates the Offspring line. Comparing the two systems shows that the way of judging original spirit and adverse spirit has similarities, though Lục Nhâm uses the Six Positions while Lục Hào uses the Six Relatives on six lines.
As for relations among lines, Sibling combines with Parent (Phụ Mẫu) because Parent generates Sibling, and is adverse to Officer (Quan Quỷ) because Officer controls Sibling. The book Lục Nhâm, volume 1, records this clearly, and this reading is also commonly applied in Lục Hào.
Why Is Sibling the Adverse Spirit When Asking About Money?
In a wealth-seeking question, the Wealth line (Thê Tài) is the useful spirit, and because Sibling controls Wealth, it becomes the adverse spirit. Tang San Buo Dich says plainly: if one encounters Sibling holding the Self line, or a Sibling line moving in the hexagram, or the Self line falling into Cycle Emptiness or Month Destruction, then seeking wealth is no different from climbing a tree to catch fish. This image is very strong: a tree has no fish, climbing it only wastes effort. The book means that wealth-seeking here meets an internal resistance of the hexagram itself, not an external circumstance.
The divination verse compiled from Toái Kim phu and Thong huyen phu also has the line "Sibling holds the Self line, do not speak of seeking wealth," meaning that when the Sibling line holds the Self line, do not discuss wealth-seeking. This view is repeated in many books and is consistent with five-element principle: Sibling controls Wealth, so Wealth is damaged.
However, note that Sibling is not always an absolutely bad sign. In cases where Sibling moves but is controlled by the Day Spirit or Month Command, or enters the Tomb, or is clashed open, its wealth-controlling effect may be reduced. There are also cases where Sibling moves to generate Offspring, and Offspring then generates Wealth, forming an indirect generative chain favorable to wealth fortune.
Table of the Eight Palaces: Palace Element, Sibling Element, and Branches
The table below is built from the core calculation: the Sibling line always carries the element of the palace, and the branches carrying that element are those that can appear in the Sibling position in hexagrams belonging to that palace.
| Palace | Palace Element | Sibling Element | Branches Carrying That Element |
|---|---|---|---|
| Qian | Metal | Metal | Zi, Chou, Yin, Mao, Chen, Si, Wu, Wei, Shen, You, Xu, Hai (depending on position) |
| Dui | Metal | Metal | as above |
| Li | Fire | Fire | Si, Wu |
| Zhen | Wood | Wood | Yin, Mao |
| Xun | Wood | Wood | Yin, Mao |
| Kan | Water | Water | Zi, Hai |
| Kun | Earth | Earth | Chen, Xu, Chou, Wei |
| Gen | Earth | Earth | Chen, Xu, Chou, Wei |
Note that in practice, the Sibling line of a specific hexagram does not necessarily carry every branch of that element. For example, the hexagram Earth Water Shi belongs to the Kan palace, and its Sibling line is the Hai Water line; the hexagram Mountain Fire Bo belongs to the Gen palace, and its Sibling line is the Xu Earth line. The table above only lists the branches that can appear; it does not claim every hexagram has all of them.
How Does Sibling Differ from Rob Wealth in Bát Tự?
This is a common question, because both concepts carry the meaning of contention, loss, and competition. The core difference lies in the frame of reference. In Bát Tự, Compare and Rob (Tỷ Kiếp) are determined relative to the day stem: Compare (Tỷ Kiên) is a stem with the same element and same yin-yang as the day stem, while Rob Wealth (Kiếp Tài) is a stem with the same element but different yin-yang. In Lục Hào, Sibling is determined relative to the element of the hexagram palace, not relative to a specific day stem.
The consequence is that in Bát Tự, Compare and Rob are fixed according to each person's chart, while in Lục Hào, Sibling changes with each hexagram cast. A person may have strong Compare and Rob in their Bát Tự chart for life, but when casting a hexagram about business, the Sibling line in that hexagram may be strong or weak depending on the Month Command and Day Spirit at the time of casting.
In meaning, both symbolize siblings, friends, rivals, and both can cause wealth loss. But the method of judgment differs: Bát Tự looks at Compare and Rob in relation to the whole chart, while Lục Hào looks at Sibling in relation to the other lines of the hexagram and to the useful spirit of the specific question.
Where Do the Schools Disagree?
One notable difference is how Sibling is assigned to natural phenomena. Old books have a tradition of assigning Sibling to wind and clouds, while Bốc Phệ Chính Tông by Vương Duy Đức assigns foul wind to Officer. This is where books disagree, and students need to know it to avoid confusion when reading materials from multiple sources.
Another point is the relation between Sibling and Wealth in marriage questions. Some books hold that a moving Sibling in a marriage hexagram is a sign of a third party or contention; others hold that other lines must also be examined before concluding. This difference reflects the level of detail and context of each school.
As for the question "Does a moving Sibling always mean losing money," the answer is no, not absolutely. A moving Sibling can mean losing money, but it can also mean having help, having friends' support, or a sign of having to share benefits. One must see which line the moving Sibling generates or controls, and whether that line is the useful spirit of the question.
Illustrative Example
Suppose one casts a hexagram about business cooperation, using LapQueLucHao to cast. The result gives the hexagram Earth Water Shi, belonging to the Kan palace, and the Sibling line is the Hai Water line. If the Wealth line in the hexagram is the Wu Fire line, then Hai Water controls Wu Fire, consistent with the principle that Sibling controls Wealth. If the Sibling line Hai Water then activates, the wealth-controlling effect is stronger, and the cooperation may meet financial obstacles or require sharing profits among many parties.
Conversely, if the question is about siblings in the family, then the Sibling line Hai Water is the useful spirit. In that case, if Hai Water is supported by the Month Command, or generated by the Day Spirit, it is a good sign for the siblings. If Hai Water suffers Month Destruction or falls into Emptiness, it is an unfavorable sign.
Practical Application and Limits
In practice, the Sibling line helps the interpreter identify who is involved, who is a rival, who is a supporter. When asking about wealth, the appearance of Sibling is a signal to be cautious, but one should not conclude absolutely that money will be lost. The whole hexagram must be examined, especially the Self line, the Other line, and the moving lines, before making a judgment.
Note also that Lục Hào is a divination system with conventional rules, not an experimental science. Conclusions are for reference only and should not replace real decisions about finance or other important matters.
