The Two Schools
Feng shui has two major schools. Form School (形势派) reads the landscape — mountains, rivers, terrain. Compass School (理气派, lǐqì pài) reads the numbers — directions, dates, and mathematical relationships.
Form School is intuitive: a site that looks good probably is good. Compass School is mathematical: a site's quality can only be determined through precise measurement and calculation.
The Luopan
The luopan (罗盘) is the Compass School practitioner's primary tool. It looks like a compass surrounded by concentric rings of Chinese characters — anywhere from 4 to 36 rings, depending on the luopan's complexity.
Each ring contains different information:
The innermost rings show the 24 mountains (二十四山) — 24 directional sectors of 15 degrees each, combining the eight trigrams, the twelve earthly branches, and the ten heavenly stems.
The middle rings show the Flying Star positions, the annual energy shifts, and the relationships between the building's orientation and the occupant's birth data.
The outer rings show more specialized information — the 72 dragons, the 120 gold divisions, and other technical data used for advanced calculations.
A master feng shui practitioner can read the luopan the way a pilot reads an instrument panel — extracting multiple layers of information from a single measurement.
The Flying Star System (玄空飞星)
The most popular Compass School method is the Flying Star system (玄空飞星, xuánkōng fēixīng). It maps nine types of energy across the eight directions plus the center of a building, creating a unique energy chart based on:
The building's facing direction — measured to within 1-2 degrees using the luopan. The building's construction date — which determines the "period" (运, yùn) of the building. The current year — which determines the annual energy overlay.
The resulting chart shows which areas of the building have positive energy (wealth, health, romance) and which have negative energy (illness, conflict, loss). The practitioner then recommends adjustments — adding water features, metal objects, or specific colors to enhance positive areas and mitigate negative ones.
The Eight Mansions System (八宅)
The Eight Mansions system (八宅, bāzhái) is simpler than Flying Stars. It divides buildings into eight types based on their facing direction and assigns each type four auspicious and four inauspicious sectors.
The system also considers the occupant's personal trigram (based on birth year and gender), creating a compatibility analysis between the person and the building. A building that is auspicious for one person may be inauspicious for another.
The Criticism
Compass School feng shui is criticized for being overly complex and unfalsifiable. The calculations are so intricate that different practitioners often reach different conclusions about the same building. When predictions fail, practitioners can always point to a variable that was not properly accounted for.
The Defense
Defenders argue that the complexity is the point — the universe is complex, and a simple system cannot capture its dynamics. The luopan's multiple rings represent multiple layers of reality, each interacting with the others in ways that require expertise to interpret.
Whether this defense is valid depends on whether you believe the underlying model is accurate. The mathematics are internally consistent. The question is whether they correspond to anything real.