Colores Domorum (Colors of the Houses)
Definition
Colores domorum is the medieval doctrine assigning a color to each pair of opposing houses, used to judge the color of a thing in a horary question. The six pairs run: 1st and 7th = white; 2nd and 12th = green; 3rd and 11th = saffron; 4th and 10th = red; 5th and 9th = honey-colored; 6th and 8th = black. It is applied to lost-object questions, the color of a disease, and electional contexts, where the color of the sought thing is read from the house holding its significator.
In Tradition
In medieval horary the color of a hidden, lost, or asked-about thing is read off the chart, not guessed. The houses are grouped into six colored pairs across the cardinal axes, and the significator of the thing — the planet standing for it — fixes which color applies by the house it occupies. Bonatti gives the rule plainly: when judging a thing in terms of color, look to the house holding the significator and judge the sought thing's color from that house.
In Practice
Use this when a horary question turns on color — what a lost object looks like, the complexion of an illness, or the appearance of something to be chosen. First identify the significator of the thing asked about: the lord of its house, or the planet otherwise signifying it. Find which house that significator occupies, then read the color from the pairing: 1st or 7th points to white; 2nd or 12th, green; 3rd or 11th, saffron; 4th or 10th, red; 5th or 9th, honey-colored; 6th or 8th, black. The pairs run along the cardinal axes, so opposing houses share a color. Treat the result as one descriptive testimony to be weighed with the rest of the judgment — the condition of the significator, the sign it occupies, and the aspects reaching it — not a standalone verdict. In medical questions the same mapping describes a disease's color; in elections, the look of the thing chosen.
Historical Origin
The colores domorum doctrine is preserved in Guido Bonatti's Liber Astronomiae (Tractate II, second part, the chapter 'On the Colors Which the Houses Signify'), in the Project Hindsight edition translated by Robert Zoller. Bonatti was an Italian writing in Latin in the thirteenth century, the principal conduit by which Arabic horary methods reached medieval Latin practice; the per-house color mapping forms part of that transmitted horary apparatus for judging lost objects and the color of things.