Hour pillar

Meaning

The hour pillar, 時柱 shízhù, is the fourth of the four pillars: the double hour of birth, one of the twelve two-hour periods the Chinese day is divided into, each named by an Earthly Branch, Zi from 23:00 to 01:00, Chou from 01:00 to 03:00, and so round to Hai from 21:00 to 23:00. Its stem follows from the day’s, so the same double hour has a different pillar on each of five days.

The tradition reads it as the pillar that comes last: the children, the later years, and what one’s work bears, the fruit after the root, the stem and the flower of the other three. The zodiac reads its branch, the hour animal, as the secret animal, the private self shown to few. Ulune keeps both senses, the outcome and the inner self, and does not read ages from the pillars.

Without a birth time there is no hour pillar, and Ulune leaves it out rather than guess: three pillars, six characters and seven points of the balance instead of nine. The chart is still read in full; the hour adds a stem, a branch and their hidden stems, which can tip the strength, the stars or an interaction one way or the other.

In practice

• On the board, the hour stands on the left, as the tradition writes the pillars; without a birth time the board shows three columns and says what the hour would add.
• The Sun’s hour: Ulune reads the hour on true solar time by default, the Sun’s own time at the birthplace; in Madrid in summer, for example, the clock runs more than two hours ahead of the Sun, enough to change the double hour.
• The edges: the double hours change at the odd hours of that clock, 23:00, 01:00, 03:00 and so on; a birth within five minutes of an edge is marked uncertain.
• The Rat hour: from 23:00 to 01:00 it straddles midnight; by Ulune’s default it is wholly the next day’s, and the split Rat hour and midnight rules are there for other schools.
• In the count, the hour weighs like the year and the day: one point for its stem, one for its branch’s hidden stems.

Across traditions

• In Japan and Korea it is the jichū of Shichū Suimei and the siju of saju, where the double hours keep their animal names.
• In Western astrology the nearest idea is the Ascendant and the houses, which also need the birth time and move on about every two hours: the part of a chart that two people born on the same day do not share.

Origin and history

The day of twelve double hours, each named by a branch, is ancient, and water clocks and the drums of the city towers kept it for some two thousand years. Li Xuzhong’s method, as Han Yu describes it in the early 9th century, read the year, the month and the day; the hour entered the reading with the school of Xu Ziping, which made the four pillars and their eight characters the standard, and the Yuanhai Ziping of the Song gives the rule of the five rats for the hour’s stem. The San Ming Tong Hui and the Ziping Zhenquan read the hour as the pillar of the children and of the end of the story, the harvest of the chart.

How Ulune calculates it

Ulune reads the hour on the birthplace’s clock, true solar time by default, local mean time or the civil clock on request, and takes the branch of the double hour it falls in. The stem follows the day’s by the classical rule of the five rats: a Jia or Ji day starts with Jia-Zi, a Yi or Geng day with Bing-Zi, a Bing or Xin day with Wu-Zi, a Ding or Ren day with Geng-Zi, a Wu or Gui day with Ren-Zi; the same as counting hours unbroken through the sixty-cycle, twelve a day.

Correspondences