Derived houses

Definition

Derived houses are a reading technique that turns one house of the chart into the "first house" of someone else, so the rest of the houses then describe that other person's affairs from your chart. The fifth house becomes a child's first house; the seventh becomes a partner's first house. Counting around the wheel from the new first delivers a derived chart for the second person without casting a new one.

In context

If you want to read your partner's career from your own chart, you can take the seventh-house cusp as their first house, count three more houses clockwise, and arrive at your fourth house as their tenth, their place of public work. Derived houses are not a substitute for casting the partner's own chart, but they offer a useful sketch when only one chart is on the table.

To go deeper

Derived houses build on the standard twelve-house framework:

• Cusp: the dividing line each house begins at.
• Ruler of a house: planet of the cusp sign.
• House system: rule that places the houses.