General concepts

Da Yun (luck pillars)

Also known as: da yundayun大运大運luck pillarsluck pillarten-year luck pillarsten year luck cycledecade luckmajor luckbazi luck cycleluck periodsdaeun대운taiunliu nian流年

Da Yun (大运), the luck pillars, are the ten-year periods of a BaZi chart. The tradition derives them from the month pillar, stepping forwards or backwards through the cycle of sixty, and reads each one as the climate of a decade. The AstroSensus calculator calculates them: ten luck pillars from the month pillar, each with its age and calendar years.

The four pillars of a BaZi chart describe the moment of birth. To speak about the time that follows, the tradition adds another layer: a sequence of pillars, each lasting ten years, called Da Yun, "great luck", or luck pillars. Every luck pillar is a stem over a branch like the natal pillars, and practitioners read it as the climate of a decade: which phases it brings, which Ten God it carries towards the Day Master, and how its branch combines or clashes with the branches of the chart. The yearly pillars, Liu Nian (流年), are then read against both the chart and the current luck pillar.

The sequence starts from the month pillar and moves one step at a time through the cycle of sixty, either forwards or backwards. The direction depends on the polarity of the year stem and, in the classical texts, on the person's sex. A yang year stem (Jia, Bing, Wu, Geng or Ren) gives men a forward sequence and women a backward one; a yin year stem (Yi, Ding, Ji, Xin or Gui) does the opposite. The year is the BaZi year, counted from Li Chun. For a month pillar Bing Yin, a forward sequence runs Ding Mao, Wu Chen, Ji Si and onwards, and a backward one runs Yi Chou, Jia Zi, Gui Hai and onwards.

The start age comes from the solar terms. For a forward sequence one counts the time from birth to the next Jie term, the one that opens the following month; for a backward sequence, the time back to the Jie term that opened the birth month. Three days count as one year, one day as four months and one two-hour period as ten days. Someone born nine days after the term with a backward sequence starts the first luck pillar at about three years of age; someone born fifteen days before the next term with a forward sequence, at about five. Before that age schools read the month pillar or the yearly pillars. Some schools also let the stem of a luck pillar colour its first five years and the branch the last five, while others read the pillar as a whole.

The sex convention is the part modern practitioners discuss most. The classical rule knows two directions tied to men and women; today some practitioners ask the person which direction to use, some show both and some keep to the sex recorded at birth. The decades are also never read alone: the same luck pillar can be described as supportive in one chart and demanding in another, depending on the Day Master and the balance of the phases. Like the rest of BaZi, the luck pillars are a traditional way of dividing a life into chapters for reflection, not a timetable of events.

The free BaZi calculator in AstroSensus calculates the luck pillars. On the result and on each saved person's BaZi page, the section "Luck cycles (Da Yun)" shows ten ten-year pillars counted from the month pillar, forwards or backwards through the cycle of sixty. The start age comes from the distance between birth and the Jie term, with three days counted as one year (one day as four months, two hours as ten days), the distance taken in whole minutes and rounded down. Each cycle is shown with its age and calendar years, the current cycle is highlighted, and the relations of its pillar with the natal pillars (stem combinations, six harmonies, three harmonies and seasonal meetings, same branch, clash, punishment and harm) are reported as present, never as good or bad and never as a transformation. The direction is an optional question: "direction of the cycles according to tradition: as for a woman / as for a man". Without an answer both directions are shown side by side. The answer stays in the browser only, nothing is sent or stored, and sex is never asked or saved in the account. The calculator also shows Liu Nian, the year pillar of the current year and the next nine with their relations to the chart, and Liu Yue, the twelve month pillars of the current year with the dates of the Jie terms that open them. Without a birth time the start of the cycles can shift by up to about four months, and the result says so. The calculator still does not assess Day Master strength, Ge Ju, Yong Shen or favourable elements, and it gives no verdict on a decade or a year.