Western Geomancy (西洋地占術)

The Geomantic House Chart — A Yes-or-No Answer Cast in Sixteen Figures

Overview

Geomancy is divination by earth: sixteen figures, each just four rows of one dot or two, that the diviner once jabbed into sand and now casts at random. Islamic and African geomancy build those figures into a shield and read its Judge — askTIAN already does that as Rammal and Khatt al-Raml. The European tradition that ran from Agrippa through the Golden Dawn does something more ambitious with the very same figures: it lays the first twelve of them across the TWELVE ASTROLOGICAL HOUSES and then answers the question the way a horary astrologer would — by PERFECTION, asking whether the figure standing for the asker (House 1) makes contact with the figure standing for the thing asked about (the house of the topic). If they connect, the matter comes to pass; if they don't, the chart is in denial and the answer is no. The four ways they can connect — occupation, conjunction, mutation, translation — each tell a different story about HOW it happens: by your own hand, with effort, by outside circumstance, or through a third party. askTIAN builds this whole Renaissance apparatus on top of the same proven, unit-tested figure engine its other geomancy systems use, adds the Part of Fortune and the Via Puncti, and is candid that this is symbolic divination, deterministic from your question — not a prediction.

Origin & history

Western geomancy entered Europe through twelfth-century Latin translations of Arabic ʿilm al-raml — Hugh of Santalla and Gerard of Cremona among the translators — and was naturalised over the following centuries. Where the Arabic tradition read the shield and its Judge, European astrologers grafted geomancy onto the framework they already knew: the twelve houses of the horoscope and the logic of horary judgment. Cornelius Agrippa gave the method its canonical Renaissance form in Book II of 'Three Books of Occult Philosophy' and a dedicated tract 'Of Geomancy'; Christopher Cattan's 'The Geomancie' (1558), Robert Fludd, and the eccentric John Heydon carried it through the seventeenth century. It was then systematised again by the Hermetic Order of the Golden Dawn in the nineteenth century, whose teaching documents (later published by Regardie and reworked by Crowley as the 'Handbook of Geomancy') fixed the version most modern practitioners learn. Today its clearest expositors are John Michael Greer ('The Art and Practice of Geomancy') and Stephen Skinner ('Geomancy in Theory and Practice'), whose worked examples askTIAN uses to verify its engine.

Geomancy was, for centuries, one of the most widely practised divination arts in the world — but the WESTERN house-chart form is a distinct branch, and askTIAN is precise about which decisions it makes. The house-mapping is genuinely contested: askTIAN uses the SEQUENTIAL method (House 1 = Mother 1, House 2 = Mother 2, … House 12 = Niece 4), which Sam Block (The Digital Ambler) calls 'the oldest and most traditional method' and which Greer teaches; the Golden Dawn proper instead distributes Mothers, Daughters and Nieces into the angular, succedent and cadent houses starting at House X, and a 'true-Agrippa' variant discards the Nieces and generates the cadent houses by addition. askTIAN implements and clearly labels the sequential method, and documents the variants rather than blurring them. A second point the engine gets right where many sources err: the Part of Fortune is summed modulo 12 (never modulo 16), and it is NOT restricted to even houses — that common claim assumes every figure has an even number of points, but Puella (5) and Laetitia (7) are odd. A third: the zodiac sign assigned to each figure uses the planetary attribution (Golden Dawn / Greer / Wikipedia), which famously does not match Agrippa's own printed list and gives the lunar-node figures Sagittarius and Virgo after Gerard of Cremona — so askTIAN flags signs as tradition-variable. And the basic Greer-faithful judgment deliberately omits house-to-house astrological aspects as an advanced overlay.

How it works

A reading begins with a cast. askTIAN seeds it deterministically from your question, the date, and your name — so the same question on the same day yields the same chart — or you can supply a true manual cast as sixteen raw dot-counts (odd → single point, even → double). From the four Mothers it derives the Daughters by transposition and the Nieces, Witnesses, Judge and Reconciler by the geomantic addition rule (two like rows make a double, two unlike make a single), exactly as the shield is built — which is why the structural guarantees hold here too: a figure added to itself is always Populus, Puer + Puella is Conjunctio, and the Judge is ALWAYS an even figure (the canonical error-check). The first twelve figures then fill the twelve houses. The querent is always House 1; the quesited house is chosen from your topic — marriage and partners and lawsuits to the 7th, money to the 2nd, career to the 10th, health to the 6th, travel and religion to the 9th, children to the 5th, and so on. The engine then tests PERFECTION between the two significators: occupation (the same figure in both houses — already at hand), conjunction (one significator beside the other's house — it perfects with effort), mutation (the two meeting elsewhere — by outside circumstance), or translation (a third figure bridging both — through an intermediary). If none occur, the chart is in denial and the answer is no. A yes is then coloured good or bad by the two figures' natures. Alongside the judgment the engine returns the Court (the two Witnesses, the Judge as overall verdict, and the Reconciler), the Part of Fortune (the sum of all twelve house figures' dots, mod 12, where a remainder of 0 means House 12), and the Via Puncti — when the Judge's Fire line is a single point, that one active point traces unambiguously up through a Witness and a Niece to the one Mother or Daughter that is the root of the matter. Everything is checked against published worked examples (the Digital Ambler shield, gold perfection cases) and the structural invariants.

Good for

Use cases

Yes-or-No Oracle

Send a question and a topic; the API resolves the quesited house, tests the four modes of perfection against the querent, and returns a clear verdict — perfects (and how) or denial — coloured by the figures' natures. A deterministic spine for a geomantic-answer feature, no LLM required.

Full House Chart

The response carries all twelve houses with their figures — each with element, ruling planet, zodiac sign, point-count and meaning — plus the complete shield (Mothers, Daughters, Nieces, Witnesses, Judge, Reconciler). Everything a chart-rendering UI needs.

The Court & Part of Fortune

Beyond the house judgment, the engine returns the Witnesses and Judge as the overall verdict and the Part of Fortune house — where the querent's material fortune flows from — for readings that want both the specific answer and the general tone.

Honest Geomancy Layer

Sequential house mapping clearly labelled (with the Golden Dawn variant documented), Part of Fortune summed mod 12 and not forced to even houses, figure signs flagged as tradition-variable, Judge-always-even enforced — a correct, transparent geomancy engine that never overclaims.

Key terms

Geomantic figure
One of the sixteen figures, each four rows of a single point (odd/active) or double point (even/passive) — from Via and Populus to Fortuna Major and Cauda Draconis. Two figures 'add' row by row: like rows make a double, unlike make a single.
Querent & quesited
The querent is the asker, always House 1; the quesited is the subject of the question, placed in the astrological house that governs it (marriage in the 7th, money in the 2nd, career in the 10th, and so on). The whole judgment turns on the relationship between their two figures.
Perfection
Whether the matter comes to pass, by one of four modes: OCCUPATION (same figure in both houses), CONJUNCTION (one significator beside the other's house), MUTATION (the two meeting elsewhere), TRANSLATION (a third figure bridging both). None of these → denial → no. The figures' natures then colour a yes good or bad.
The Court
The shield's verdict alongside the houses: the Right Witness (querent / past) and Left Witness (quesited / what is coming) combine into the Judge — the overall outcome, always an even figure — and the Judge plus Mother 1 gives the Reconciler, how it settles for the querent.
Part of Fortune
Where the querent's material fortune flows from: the total points of all twelve house figures, taken modulo 12 (a remainder of 0 means House 12). It is mod 12, never mod 16, and — because odd-pointed figures like Puella and Laetitia exist — is not restricted to even houses.
Via Puncti
The 'Way of the Point': when the Judge's Fire line is a single point, that one active point can be traced unambiguously upward — Judge → Witness → Niece → Mother or Daughter — to the single figure that is the root cause of the matter. Only Judges with a single Fire line have one.
Sequential vs Golden Dawn mapping
How the twelve figures fill the houses. askTIAN uses the SEQUENTIAL method (House 1 = Mother 1 … House 12 = Niece 4), the oldest and most traditional; the Golden Dawn proper uses an angular/succedent/cadent placement. The engine labels its choice and documents the variant.

API

The askTIAN Western Geomancy API casts the full Renaissance / Golden Dawn geomantic house chart from a question — deterministically seeded from the question, date and name, or from an explicit manual cast of sixteen dot-counts. It reuses the same unit-tested figure engine as Rammal and Khatt (so Via+Via=Populus, Puer+Puella=Conjunctio and the Judge-always-even error-check all hold), then projects the first twelve figures into the twelve astrological houses by the sequential (Greer/traditional) mapping, routes the topic to its quesited house, and judges the question by PERFECTION — occupation, conjunction, mutation or translation, else denial — with the yes/no coloured by the two significators' natures. The response returns the complete shield, the twelve-house chart (each figure with element, planet, zodiac sign, points and meaning), the perfection judgment, the Court (Witnesses, Judge, Reconciler), the Part of Fortune (sum of the twelve house figures' dots mod 12), the Via Puncti, a transparent 0–100 symbolic score, and a best-effort LLM reading in six parsable sections. Correctness and honesty are the priority: the engine is locked by unit test against the Digital Ambler worked shield and gold perfection cases (House 9 occupation, House 7 mutation, House 10 conjunction, House 6 denial, Part of Fortune 80 points → House 8) and the structural invariants; it labels the sequential house mapping (documenting the Golden Dawn variant), sums the Part of Fortune mod 12 without forcing even houses, flags figure signs as tradition-variable, omits the advanced aspect overlay, and is candid that this is symbolic divination, not prediction. Set interpretation:false for structured data only.

Endpoint: POST /trpc/geomancy.cast — 7 TIAN Points. See the API documentation and Playground.