The sixty pillars

How sixty comes out of ten and twelve

A pillar is one Heavenly Stem on top of one Earthly Branch. There are ten stems and twelve branches, so the obvious guess is 120 combinations — but only sixty ever occur. The two cycles advance together, one step at a time, and because ten and twelve share a factor of two, the pairing only returns to its starting point after sixty steps. That is why the first pillar is Jia Zi and the sixty-first is Jia Zi again, and why an odd stem never meets an odd branch.

This is the same cycle that names years, months, days and hours. 1984 was a Jia Zi year; so was 1924, and so will 2044 be. A chart is simply four of these pairs taken from four different cycles.

The four things every pillar carries

• The stem — the visible element on top. In the Day pillar this is the Day Master, the reference point of the whole chart.
• The branch — the animal and its fixed element, plus the season it belongs to.
• Hidden stems — one to three further stems buried inside the branch. They are why a branch is never only its surface element.
• The nayin — a separate "sound element" assigned to the pair. It is a classical layer of meaning, not a calculation of the chart's balance.

A fifth layer is the twelve stages: how strong the stem is at that particular branch, from Birth through Peak to Severed and back. It is a qualitative reading of the same relationship the stems and branches already describe.

The twelve stages, in one line each

All sixty

Ordered as the cycle runs. Each row links to the pillar's own page, which gives the elements, the hidden stems and the stage in full.