TL;DR: Tam Thức is the collective name for three ancient Eastern divination arts: Thái Ất, Kỳ Môn Độn Giáp and Lục Nhâm. Thái Ất is mainly used to divine the affairs of the sovereign and the state, Kỳ Môn Độn Giáp is mainly used in military strategy, while Lục Nhâm is more compact and flexible and so is used for many kinds of specific questions; these boundaries are tendencies rather than absolutes. All three are ancient divination arts, and none has a scientific basis for predicting the future.
What is Tam Thức and why are the three schools grouped under one name?
Tam Thức is the collective name for three schools of ancient Eastern divination: Thái Ất, Kỳ Môn Độn Giáp and Lục Nhâm. According to Ho Peng Yoke (2003), Chinese Mathematical Astrology: Reaching Out to the Stars, RoutledgeCurzon, the three schools operate on the same common principles of divination such as yin and yang, the five elements, and the heavenly stems and earthly branches, but each school has a different subject and scale of divination; the nine palaces of the Lạc Thư are used only in Thái Ất and Độn Giáp, while Lục Nhâm sets up its board on the twelve earthly branches. The word "thức" (式) here refers to the thức board, that is, the rotating board used to cast a chart; Ho Peng Yoke translates Tam Thức as three cosmic boards, and notes that Yan Dunjie identified one excavated Han-period board as a Thái Ất board, though in Ho's view it is at best a rudimentary form of the board used in the Song.
According to Ho Peng Yoke, Thái Ất is mainly used to divine the affairs of the king and the state; Kỳ Môn Độn Giáp is mainly used in military strategy; Lục Nhâm is lighter and more flexible, so it is used for many kinds of specific questions. This boundary is the main tendency, not absolute.
It should be said clearly from the outset: this is ancient divination, and there is no scientific basis for prediction.
In what ways do Thái Ất, Kỳ Môn Độn Giáp and Lục Nhâm differ?
The fundamental difference lies in the subject of divination and the unit of time used to set up the board. Thái Ất sets up its board mainly by the year (tuế kế), with further methods by month, day and hour, directed at great events such as war, natural disaster, and the rise and decline of a nation. Kỳ Môn Độn Giáp sets up its board by the hour, and can also do so by day and month, directed at concrete actions such as sending out troops, travelling far, choosing a direction, and deploying forces. Lục Nhâm sets up its board by the hour and by the day, directed at a specific question about people, work, relationships, or litigation.
| Criterion | Thái Ất | Kỳ Môn Độn Giáp | Lục Nhâm |
|---|---|---|---|
| Subject of divination | Great affairs of the state, the times, war, natural disaster, rise and decline | Action, direction, deployment of forces, choosing the moment to act | Specific people and matters, relations between parties, the course of an affair |
| Unit of time for setting up the board | Year (tuế kế); also methods by month, day and hour | Hour, day, month, year; usually set up by the hour | Hour and day |
| Board structure | A sixteen-part board (twelve branches, four corner trigrams) with Thái Ất, host count, guest count, the generals and the spirit markers | The nine palaces of the Lạc Thư with the Three Marvels, the Six Rites, the Nine Stars, the Eight Gates, the Eight Spirits | The heavenly board, the earthly board, the four courses, the three transmissions |
| Classic texts | Thái Ất Kim Kính Thức Kinh (Vương Hi Minh, Tang dynasty) | Yên Ba Điếu Tẩu Ca, the various Kỳ Môn texts handed down | Lục Nhâm Đại Toàn |
The table above is only a general framework. In practice, texts may divide things in more detail, and the popularity of each school also varies by period and by region.
What is Thái Ất used to divine?
Thái Ất is mainly used to divine the affairs of the king and the state. According to Ho Peng Yoke (2003), Chinese Mathematical Astrology: Reaching Out to the Stars, RoutledgeCurzon, the most important role of Thái Ất is to divine the affairs of the king and the state, and there are also Thái Ất methods by month, day and hour for officials and common people. Ho Peng Yoke also remarks that the Thái Ất calculation is cumbersome and its scope of divination is hard to compare with the other two boards, so among the people this is the least known school within Tam Thức.
How is the Thái Ất board set up?
According to Ho Peng Yoke (2003), Chinese Mathematical Astrology: Reaching Out to the Stars, RoutledgeCurzon, the Thái Ất board consists of concentric rings, each ring divided into sixteen parts: the twelve earthly branches and the four trigrams Càn, Khôn, Cấn, Tốn, of which eight parts are marked with palace numbers from 1 to 9 (except palace 5 in the centre); the third ring records the names of sixteen spirits. On the board are Thái Ất, host count, guest count, the host and guest generals, along with many spirit markers. For the hour-based method, the Thái Ất Kim Kính Thức Kinh records: in the yang dun sequence Thái Ất starts at Càn from the winter solstice, in the yin dun sequence it starts at Tốn from the summer solstice. The Kim Kính Thức Kinh also contains methods for calculating the host count, the guest count, Thủy Kích, and the methods of Tứ Thần, Thiên Ất, Địa Ất, and Trực Phù.
Why is Thái Ất often tied to affairs of state?
The Kim Kính Thức Kinh describes Thái Ất as the spirit of the Heavenly Emperor, commanding the sixteen spirits and knowing which states will meet wind and rain, flood and drought, war, famine and epidemic. The book also assigns the methods by rank: the king uses the year count, ministers the month count, officials the day count, while the hour count is shared by high and low alike.
What is Kỳ Môn Độn Giáp used to divine?
Kỳ Môn Độn Giáp is mainly used in military strategy, according to Ho Peng Yoke (2003), Chinese Mathematical Astrology: Reaching Out to the Stars, RoutledgeCurzon. This is the school with a multi-layered board structure, consisting of the Three Marvels, the Six Rites, the Nine Stars, the Eight Gates and the Eight Spirits stacked on the nine palaces. Kỳ Môn Chỉ Quy (Chu Hạo Văn, Qing dynasty) lists the components: the nine palaces, the eight trigrams, the eight gates, the three marvels, the six rites, the nine stars, the nine spirits, trực phù, trực sử, and yin and yang in forward and reverse order.
What layers does the Kỳ Môn board have?
The Kỳ Môn board is usually described as having four main layers: the stem-marvel layer (the Three Marvels, the Six Rites), the star layer (the Nine Stars), the gate layer (the Eight Gates) and the spirit layer (the Eight Spirits or Nine Spirits depending on the school). On the foundation of the nine palaces of the Lạc Thư, the person setting up the board arranges these layers by the hour and by whether the cục is Yang Dun or Yin Dun.
Why is Kỳ Môn tied to action?
Because the Kỳ Môn board is set up by the hour, it gives information that is tied to a moment in time. Users of Kỳ Môn often ask questions such as: which direction should I go, when should I act, how should I deploy my forces. The Yên Ba Điếu Tẩu Ca recorded in Kỳ Môn Chỉ Quy contains the methods of Thiên Độn, Địa Độn and Nhân Độn; that book also records the inauspicious patterns Đại cách (Canh gia Quý) and Tiểu cách (Canh gia Nhâm, which the song calls Thượng cách). These are internal concepts of the school, not common terminology.
What is Lục Nhâm used to divine?
Lục Nhâm is lighter and more flexible than the other two boards, so it is used for many kinds of specific questions, according to Ho Peng Yoke (2003), Chinese Mathematical Astrology: Reaching Out to the Stars, RoutledgeCurzon. Ho Peng Yoke also notes that some diviners use Lục Nhâm alongside other methods, and that both Độn Giáp and Lục Nhâm are also used to divine the weather.
What is the structure of the Lục Nhâm board?
The Lục Nhâm board consists of the heavenly board, the earthly board, the four courses and the three transmissions, according to Ho Peng Yoke (2003), Chinese Mathematical Astrology: Reaching Out to the Stars, RoutledgeCurzon. The four courses consist of four courses set up from the stem and branch of the day on the heavenly board and the earthly board; the three transmissions (initial transmission, middle transmission, final transmission) are drawn from the four courses.
Why is Lục Nhâm close to everyday life?
Because the questions put to Lục Nhâm are usually very specific: a lawsuit, a journey, a relationship, a piece of news about to arrive. The Lục Nhâm board is set up by the hour and the day, so it gives an answer tied to a moment in time for a matter currently unfolding.
Are the three schools truly separate, or are there places where they are used together?
The three schools share a common foundation but do not replace one another. According to Ho Peng Yoke (2003), Chinese Mathematical Astrology: Reaching Out to the Stars, RoutledgeCurzon, Lục Nhâm is more flexible and convenient than the other two boards because it is light, and some diviners use it alongside other methods; Độn Giáp and Lục Nhâm are also used to divine the weather.
Do the schools agree on Tam Thức?
No. Even within each school the authorities disagree. In Thái Ất, Vương Hi Minh criticised Tống Côn's setting of the upper origin and fixed his own accumulated year count. In Lục Nhâm, the Tứ Khố abstract of the Lục Nhâm Đại Toàn writes that after long transmission the teachings split many ways: those who discuss only the course patterns are too rigid, those who rely only on the category spirits are too coarse, and those who mix in the spirit markers are too scattered. The division of labour used in this article (Thái Ất for the king and the state, Kỳ Môn for warfare, Lục Nhâm for many kinds of specific questions) follows Ho Peng Yoke; when reading other materials, check which convention they follow.
Does Tam Thức have a scientific basis for prediction?
No. Tam Thức is ancient divination, and there is no scientific basis for prediction. Even the compilers of the Qing dynasty Tứ Khố Toàn Thư wrote that the section on verifications in the Thái Ất Kim Kính Thức Kinh is for the most part erroneous, and that assigning fortune and misfortune by field allocation is an unfounded imposition. Tam Thức should be read as a tradition of knowledge and a way of thinking about time, not as a tool of prophecy.
Where should one begin when reading about Tam Thức?
If you want to study Tam Thức as a tradition of knowledge, you should begin with the general conceptual framework: the heavenly stems and earthly branches, the five elements, the eight trigrams, and the nine palaces. After that, choose one school to go deeper into, usually Lục Nhâm because it is close to everyday questions, or Kỳ Môn because its materials are more widely available. Thái Ất is usually left for later because its calculations are cumbersome and its board structure is complex. With Kỳ Môn, the opening questions and answers in Kỳ Môn Chỉ Quy on the nine palaces, the eight gates, the three marvels, the six rites, the nine stars and the nine spirits can serve as a starting point. Whichever direction you take, you should keep an objective attitude: this is ancient divination, not predictive science.
