Foundations of Astrology: Campanus

The Campanus house system is a space-based method of chart division developed by the 13th-century Italian mathematician and astrologer Giovanni di Campano. Unlike time-based systems such as Placidus or Koch, Campanus divides the prime vertical—the great circle passing through the zenith, nadir, and east-west points of the horizon—into twelve equal 30-degree segments. These segments are then projected onto the ecliptic to determine the house cusps, creating houses of unequal size that vary with geographic latitude. What distinguishes Campanus is its emphasis on spatial orientation rather than temporal flow. It treats the heavens as a spherical dome surrounding the observer, dividing that dome into equal sectors of experience. This geometric approach appeals to astrologers who value mathematical elegance and those who work with techniques emphasizing the actual positions of planets in local space. The system has found particular favor in mundane astrology and in approaches that consider the observer's direct relationship with the celestial sphere. Symbolically, Campanus reflects a worldview centered on presence and perspective. It suggests that meaning arises from where we stand in relation to the cosmos—our literal horizon and the dome of sky above. This spatial emphasis encourages reflection on how environment, location, and viewpoint shape our experience of life's twelve archetypal domains. For those drawn to geometric beauty and observational awareness, Campanus offers a house system grounded in the immediate, embodied encounter between earth and sky.