空亡

空亡, the void, is the two branches missing from the decade (旬) the day pillar belongs to.

Cutting the sixty in tens leaves twelve branches against ten stems, so two remain over, and those two are the void.

Where the hour branch is void, the seat of children and the late years is read as standing empty.

The seat of the Latter Soul stands empty. Measure out the later years beforehand and they do not come as measured.

Better to spend what is held now than to reckon what is to be left.