TL;DR: Hồi đầu sinh is when a moving line transforms into a new line that generates it back; hồi đầu khắc is when the transformed line controls the original moving line. Hóa mộ and hóa tuyệt are when a moving line transforms into the Tomb or Extinction stage of the Twelve Stages cycle; hóa không is when it transforms into the void period. Tăng San Bốc Dịch (Dã Hạc lão nhân) holds that fortune and misfortune depend not only on the name of the transformation but also on the strength of the moving line and the day and month, so hồi đầu khắc or hóa mộ is not always an ill omen.
What Are Hồi Đầu Sinh, Hồi Đầu Khắc, Hóa Không, Hóa Mộ, and Hóa Tuyệt?
In Lục Hào, every moving line transforms into a new line called the transformed line. When the transformed line generates back the original moving line, it is called hồi đầu sinh (回頭生). When the transformed line controls back the original moving line, it is called hồi đầu khắc (回頭剋). When a moving line transforms into the void period it is called hóa không (化空); when it transforms into the tomb of its own element it is called hóa mộ (化墓); when it transforms into the extinction palace of its own element it is called hóa tuyệt (化絕). These rules are discussed at length in Tăng San Bốc Dịch, written by Dã Hạc lão nhân of the Qing dynasty and expanded by Lý Văn Huy.
These names speak only of the relationship between a moving line and its own transformed line.
What Is the Mechanism by Which the Moving Line Transforms and Then Acts Back on the Original Line?
When casting a hexagram, any line with three heads or three tails is moving and transforms into a line of the opposite yin or yang polarity. That transformed line carries a new earthly branch and has a Five Elements relationship with the original moving line. Four main possibilities:
- The transformed line generates the moving line: hồi đầu sinh, strengthening the moving line.
- The transformed line controls the moving line: hồi đầu khắc, weakening the moving line.
- The transformed line has the same element as the moving line: called hóa tiến thần or hóa thoái thần, depending on direction.
- The transformed line clashes with or combines with the moving line: called hóa xung or hóa hợp.
Tăng San Bốc Dịch gives the example of a Thế line that is Tuất earth; if it moves and transforms into Tị fire or Ngọ fire, it is called hồi đầu sinh Thế; if it transforms into Dần wood or Mão wood, it is called hồi đầu khắc Thế; transforming into Thìn earth is hồi đầu xung Thế, and into Mão wood is hợp Thế[1]. The book reads these four directions of action alongside the other three forces: the month, the day, and other moving lines in the hexagram.
Why Is Hồi Đầu Khắc Not Always an Ill Omen?
This is the point where Tăng San Bốc Dịch revises earlier Lục Hào books. An old commentary quoted by the book wrote: whenever the Dụng line moves and transforms into tomb, extinction, or void, "bất luận công tư đại tiểu chi sự, giai chủ bất thành", meaning all matters will not succeed, and in divination of illness the person dies[2]. Dã Hạc lão nhân argues strongly against this: if the moving line is in a strong phase, or is generated and supported by the day and month, then hóa mộ and hóa tuyệt do not reach the level of great misfortune. Specifically:
- Hóa mộ: wait for a day or month that clashes to open the tomb, then the matter succeeds. For example, if the moving line is Wood and transforms into Mùi (Wood's tomb is at Mùi), then on a Sửu day or month that clashes Mùi open, the matter responds.
- Hóa tuyệt: wait for a day or month that generates and supports that line, then the matter succeeds.
- Hóa không: wait for the day it exits the void, then the matter responds. The book states clearly that it has been verified many times: in divination of plans, on the day of exiting the void the matter will surely succeed; in divination of recent illness, on the day of exiting the void the person will surely recover[2].
Conversely, hồi đầu sinh is not always good. If the transformed line that generates back is a strong inauspicious spirit, then hồi đầu sinh only makes the inauspicious spirit stronger. A transformed line also has a limited reach. The book's chapter on movement, transformation, generation, control, clash and combination says that a transformed line only generates, controls, clashes or combines with the moving line in its own position, not other lines, and other lines cannot act on the transformed line either; only the day and month can. The book's example is Khôn changing to Hỏa Địa Tấn: the Thế line Dậu metal moves and transforms into Tị fire, which controls Dậu back but no other line; the fourth line Sửu earth moves and generates the Thế line Dậu metal, but cannot generate the Dậu metal it transforms into itself[3].
Quick Reference Table for Tomb and Extinction by Five Elements
The table below follows the common convention in Lục Hào and is used by Tăng San Bốc Dịch when a moving line transforms. This is a convention of the school, not astronomical data.
| Five Elements | Birth | Tomb | Extinction | Womb | Nourishment |
|---|---|---|---|---|---|
| Metal | Tị | Sửu | Dần | Mão | Thìn |
| Wood | Hợi | Mùi | Thân | Dậu | Tuất |
| Water | Thân | Thìn | Tị | Ngọ | Mùi |
| Fire | Dần | Tuất | Hợi | Tý | Sửu |
| Earth | Thân | Thìn | Tị | Ngọ | Mùi |
How to read the table: if the moving line is Wood and transforms into Mùi, it is called hóa mộ; transforming into Thân is called hóa tuyệt; transforming into Hợi is called hóa trường sinh. Water and Earth share the same Birth at Thân, the same Tomb at Thìn, and the same Extinction at Tị. This is a point of difference from Tử Bình, where Earth is often placed at Birth in Dần according to some schools.
How Do Hóa Không and Tuần Không Differ?
Tuần không refers to the two earthly branches missing from a ten-day cycle of stems and branches, since ten stems pair with only ten of the twelve branches. For example, in the Giáp Tý cycle, Tuất and Hợi are void; in the Giáp Tuất cycle, Thân and Dậu are void. A line carrying an earthly branch that falls in the void period is called a void line.
Hóa không is when a moving line transforms into a line that falls in the void period. When a moving line that is already void transforms into a line that is also void, Bốc Phệ Toàn Thư calls it "không hóa không" and holds that it is void yet not fully void: in the Giáp Thìn cycle, a void Dần line moves and transforms into Mão, also void, and the line counts for half, since Dần has already borne the void and Mão is no longer counted as void; the book quotes Kim Tỏa Huyền Quan: "trùng không bất không"[4]. Tăng San Bốc Dịch goes further: not only không hóa không, but any line that has moved is not counted as void, and good or bad fortune comes due in the month or day that clashes or fills the void[2].
This distinction matters because many beginners see the word "void" and discard the line, leading to wrong readings. Bốc Phệ Toàn Thư distinguishes true void (all six lines are still and the Dụng line falls void by itself, so nothing succeeds) from void as refuge (the Dụng line is being punished, clashed, controlled or harmed by the day or a moving line while void, so the matter is only briefly blocked and succeeds after the cycle passes)[5].
Hóa Mộ, Hóa Tuyệt, Hóa Không: Fortune or Misfortune Depends on Which Line?
Bốc Phệ Toàn Thư has a concise principle: inauspicious spirits should enter the tomb, auspicious spirits should not enter the tomb[6]. That means:
- If the Dụng line, Thế line, Wealth line, or Officer line needs to succeed and transforms into tomb, extinction, or void, the matter is often delayed, slow, or must wait to succeed.
- If the Kỵ line or Ghost line is causing trouble and transforms into tomb, extinction, or void, the bad influence is locked away, which is good.
A line's strength still has to be weighed with the day and month. Tăng San Bốc Dịch cites a hexagram in which the Ghost line Dần wood moves to control the Thế line, but the Thế line is Thìn earth supported by the month, and the Sửu earth line moves and transforms with hồi đầu sinh to help it, so the Thế line is strong enough to hold out, though the person later still came close to danger before being rescued[2].
Comparison with Other Books
Bốc Phệ Toàn Thư (edited by Diêu Tế Long, 1630) precedes Tăng San Bốc Dịch and holds a fairly strict view: if the Dụng line moves and transforms into tomb, extinction, or void, "bất luận công tư đại tiểu chi sự, giai chủ bất thành", and in divination of illness the person dies. Tăng San Bốc Dịch of the Qing dynasty revises this: it still sees it as a sign of delay, but if the line is strong or is generated and supported by the day and month, it can still succeed, only later.
Dịch Mạo (Trình Lương Ngọc, 1664) says that a transformed line following the Ghost into the tomb must be judged as a true tomb or a false tomb: taking a Fire Officer line whose tomb is Tuất as the example, a Thìn day clashing Tuất makes it false, a Tuất month filling the tomb makes it true, and a Tuất that is void or broken is not a true tomb either[7]. This view is close to Tăng San Bốc Dịch in weighing the name together with the day and month.
The three books do not contradict on the mechanism, only differ in the degree of severity in interpretation. Students should know all three to avoid mechanically applying one book.
Application Suggestions from Nhật Nguyệt
When encountering a moving line that transforms into tomb, extinction, or void in practice, read in this order:
- Determine what line is moving, what line it transforms into, and the Five Elements relationship between them.
- Consult the tomb and extinction table to know whether this is a real hóa mộ or just a transformation into a line of the same element but a different branch.
- Check whether the day and month generate and support the moving line, whether they clash to open the tomb, whether they exit the void.
- Check whether that moving line is the Dụng line or the Kỵ line, and from there judge fortune or misfortune.
This reading does not assert absolute results, it is only an analytical framework of the Lục Hào school. The same hexagram can yield different results for different interpreters, so the final conclusion should still be cautious.
