The four quadrants
The two pairs of angles — ascendant/descendant and midheaven/imum coeli — divide the chart into four quarters. Each covers three houses, and the division says something before a single planet has been looked at.
The two ways the chart is halved
Above and below — the horizon line. What stands above it was visible in the sky at birth; what stands below was beneath the horizon. The upper half counts as the public sphere, the lower as the private one.
Eastern and western — the meridian line. The eastern half (houses 10 to 3, around the ascendant) counts as the self-determined one, the western (houses 4 to 9, around the descendant) as the one others have a share in.
The four quadrants
- Houses 1–3, below the horizon, eastern — the beginning: the person themselves, what they have, their immediate surroundings. Self-determined and not yet public.
- Houses 4–6, below the horizon, western — origins, what comes out of the person, daily labour. Private, but shaped by others as well.
- Houses 7–9, above the horizon, western — the other person, what is shared, what is far away. Public and shaped by others.
- Houses 10–12, above the horizon, eastern — office, allies, withdrawal. Public and self-determined again.
The circle therefore runs from the inside outwards and back again: from the individual by way of origins to the other person, to the world and finally into withdrawal.
How the quadrants are used
A striking cluster in one quadrant is a first observation — no more than that. It says where the weight of a life lies, before anything has been settled about the condition the planets there are in.
And condition decides. Five planets in the fourth quadrant, all in fall and with no aspect to the ascendant, describe something other than a single dignified planet on the midheaven.
A caveat about the angles themselves
The quadrants depend entirely on the time of birth. An hour of uncertainty shifts the ascendant by as much as a whole sign — and with it every quadrant boundary.
Anyone working from an approximate birth time should therefore not interpret this level. The position of the planets in the signs remains valid; the houses and quadrants do not.
See also: the twelve houses, the ascendant.