天干五合

tiān gān wǔ hé · Stem Five Harmonies

Deep Oracle Editorial Team · 2026-08-08 · 2 min read

Stem five harmonies (天干五合) are the five pairs the ten heavenly stems form: 甲己, 乙庚, 丙辛, 丁壬 and 戊癸, each with an element it is said to transform to. Where the same pairing occurs between stems hidden inside branches rather than revealed ones, this site treats it separately, under hidden harmony (暗合).

PairTransforms to
甲–己
乙–庚
丙–辛
丁–壬
戊–癸

Ziping Zhenquan's chapter on stems that combine yet do not combine (《子平真诠·论十干合而不合》) exists to make a single point: the pairing being present is not the same as the combination taking effect. It separates two ways a combination fails. One is obstruction — with a 庚 standing between a 甲 and a 己, the 甲 cannot reach past a stem that controls it, and the chapter treats this as a combination that dares not combine, present in name only. The other is distance: a 甲 in the year stem and a 己 in the hour are described as being of one mind but far apart, a half-combination whose effect the chapter puts at two or three parts in ten.

The chapter then limits the doctrine further. Some combinations do no harm at all, as when one of two revealed officers is combined away and one is left. And a combination made by the day stem itself is not a case of something being taken away, since the day master is combining what belongs to it. Where two stems contend for one the chapter allows the affection to be divided rather than destroyed, and notes that if the two are not adjacent there is no contention at all.

Worked example. In the example chart below the 乙 sits in the year stem and the 庚 in the hour, with two stems between them: by the chapter's account a combination that cannot combine, worth two or three parts in ten.

Worked example (solar 1975-02-11 16:00, female, computed by this site's engine):

YearMonthDayHour
Stems乙 (正官)戊 (比肩)戊 (DM)庚 (食神)
Branches

Pattern: 七杀格 · Strength: 极弱 (engine verdicts)

Classical sources cited

  • 子平真诠·论十干合而不合

Lookup tables are generated from this site's chart engine; quotations are verified against the cited works.

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In the classical texts

Passages in the classical texts held on this site where the term occurs, transcribed from the named edition. The texts do not necessarily use the term the way it is used today.

  • 一已合两甲两甲合一巳是谓隂阳偏枯如妇多夫少夫多妇少相争相妬皆乱之道也故曰偏则乱壶中子云一气偏枯老为俗物是也天元变化书云天干合阳得隂合福慢隂得阳合福故甲得已合为财已得甲合为官阳干遇隂干合止得干合之福隂干遇阳干合又得正官合辅为而里福故慢不同余干例推又曰干合更得支合在一旬内如甲戌见巳卯甲辰见巳酉之类谓之君

    三命通会论十干合

  • 歌云命若无冲有元运只怕刑冲破命中刑冲若临相滋助定保珍材意气雄】合则少兮受寡助之力鬼则多兮招毁谤之端【五行合者合神有三一曰干合二曰六合三曰三合其用则一也相合相生主吉相合相伤主凶如甲巳乃中正之合乙庚为仁义之合丙辛为威制之合丁壬为隂匿之合戊癸为无情之合合者贵乎得中而不可偏一偏一则乱此十干之合理也支合者子与

    三命指迷赋三命指迷赋(二)

  • 此十干合化之义也。

    子平真诠论十干配合性情

  • 干合论

    命理约言卷三论四十八篇(一)

  • 又如戊逢癸亥,是干正支邪,戊午丙子支正干邪,然水火阴阳相和,则不如干合为正也。

    李虚中命书通理物化

  • 戊子(戊子癸水财),己亥(己亥甲木官,壬水财),壬午(壬午丁火财,己土官),癸巳(癸巳戊土官,丙火财)之类,皆支中人元与天干相合,此乃下财官,旺则得其用矣,不直冲坏。

    滴天髓地支论

Heavenly Stem Combinations — Rules and Transformation