Ba Zi Clashes and Combinations: How the Twelve Branches Meet

The wheel first

The twelve branches sit in a fixed circle, in the order of the months and the hours: Zi 子, Chou 丑, Yin 寅, Mao 卯, Chen 辰, Si 巳, Wu 午, Wei 未, Shen 申, You 酉, Xu 戌, Hai 亥. Each carries an element — Zi and Hai Water, Yin and Mao Wood, Si and Wu Fire, Shen and You Metal, and the four Earth branches Chou, Chen, Wei and Xu at the corners between seasons. Every relationship below is a distance or a symmetry on that circle: opposite points clash, mirror points combine, points four apart form a triad, and neighbours form a season.

The Earthly Branches entry has the branches themselves; what follows is what they do to one another.

The Six Combinations (六合)

The six combinations are the six pairs of branches that mirror each other across the axis running between Zi–Chou on one side and Wu–Wei on the other, and each pair is said to produce an element:

A combination reads as attraction and binding. Two combined branches are engaged with each other and less available to anything else — which is a benefit when the branch that gets tied up was hostile to the Day Master, and a cost when it was the branch the chart depended on. Whether the produced element actually manifests is a school question that turns on the month and on the surrounding stems; the pairing itself is not.

Structurally, the combinations run in opposite directions around the wheel from the two ends of the axis: Zi meets Chou beside it, then Hai meets Yin, Xu meets Mao, You meets Chen, Shen meets Si, and Wu meets Wei at the far end. Once you see the axis you can reconstruct all six from memory of one.

The Six Clashes (六沖)

The six clashes are the six pairs of branches directly opposite each other on the wheel — six positions apart, and always a pair of opposed elements or a pair of Earth branches:

A clash reads as movement, disruption or separation in the domain of the pillar it strikes — the Year pillar for elders and origins, the Month for parents and career, the Day for the spouse and the self, the Hour for children and late life. The cardinal clashes, Zi–Wu and Mao–You, are read as the most forceful because they set the four peak points of the elements against each other. The two Earth clashes are a case apart: Chou, Chen, Wei and Xu are the four vaults, and a clash between two of them is the classical key that opens a vault and releases the element stored inside, which can be the most welcome event in a chart rather than the least. The clash that most people meet first is the annual one: a year whose branch clashes a natal branch is the year of "offending the Tai Sui".

The Three Harmonies (三合) and the Directional Combinations (三會)

The four three-harmony triads are sets of three branches spaced four positions apart that together form a single element, and each triad is the birth, peak and tomb of its element in the Twelve Stages of Growth — which is not a coincidence but the reason the three belong together:

A full triad in a chart, or completed by a transit, creates a strong and coherent presence of its element — an entire life cycle of Water, say, standing in the chart at once. Two of the three is a half combination (半合), counted when the peak branch is one of the two and much weaker without it.

The four directional combinations are the three consecutive branches of a season, and they form the season's element:

A directional combination is the strongest of all the branch relations — three months of one element standing together — and most schools rank the relations in that order of force: directional combination, then three-harmony, then the six combinations, with the clashes assessed against whichever of those is present.

The Six Harms (六害)

The six harms are derived, not listed: the harm of a branch is the branch that clashes with its combination partner. Zi combines with Chou; Chou is clashed by Wei; so Zi and Wei harm each other. Run the same two steps from each branch and all six pairs appear:

That derivation is also the meaning. A harm is the third party that breaks a bond — the branch whose arrival disturbs a combination that was holding. Where a clash is open disruption, a harm reads as quiet undermining: the relationship that erodes rather than breaks, the ally who turns out to have a prior loyalty. It is the mildest of the hostile relations and the one most often over-read by beginners, who treat every harm as a clash.

The Penalties (刑)

The penalties are three groups of different branches plus four branches that penalise themselves:

A penalty reads as pressure turned inward: strain that comes from a position rather than from an opponent, self-inflicted difficulty, the cost of a role. The three-branch groups are read at full strength only when all three are present, and at partial strength for any two; the self-penalties need nothing but repetition — two Chen in a chart, or a Wu year over a natal Wu. Penalties are the relation the schools disagree about most, both in weight and in interpretation, and the honest position is that they are read as a secondary signal beside a clash or a combination rather than as an event in themselves.

How a date reaches a chart

Inside the natal chart, adjacent pillars interact most strongly — the Day branch with the Month and with the Hour — and a relation between the Year and Hour branches, separated by two pillars, is counted lightly. The Day branch carries the most weight of all, because it is the seat of the Day Master and the spouse palace at once, so a clash or a combination to it is read in the person and in their closest relationships before anywhere else.

Outside the chart, every unit of time is itself a stem and a branch — a Luck Pillar for a decade, a year, a month, a day — and it enters the chart through exactly these tables. A Zi year clashes a natal Wu; a Chou month combines a natal Zi; a Shen day completes a natal Zi and Chen into a Water triad. When several relations apply at once, the order of assessment is the order of strength given above, and the classical principle that a combination is read before a clash — 合解沖, a combination releases a clash — decides most of the contested cases, with schools differing on how far the release goes.

This is also what a daily Ba Zi reading is actually doing when it tells you the day "clashes your Month pillar" or "combines with your Day branch". Our own daily reading flags exactly these events against your four natal branches — clash, combination, harm, penalty and a completed three-harmony triad — and the compatibility reading applies the same tables between two people's Day branches, where a combination or a clash between two charts is the oldest form of Chinese relationship astrology there is. The directional combinations are stated here for completeness; they are a matter of the natal chart's season rather than of a single day, and no daily reading flags them.

The one-page table

Every branch with all its partners. Read your four natal branches down the left column and you have every relation a date can form with your chart:

None of these relations is good or bad on its own. A clash that opens a vault holding your useful element is a gift; a combination that ties up your only Resource is a loss; a triad that completes an element your Day Master is already drowning in is the last thing the chart needed. The tables say what meets what. Whether the meeting helps depends on what the chart needs, which is decided — as with the Ten Gods — by assessing the Day Master's strength before reading anything else.

Start with your eight characters. Compute the pillars, write the four branches down the left of the table above, and every year, month and day that arrives becomes a row you can read. The Branch Interactions entry keeps the short form, and the Ba Zi learn hub covers the system the branches sit inside.