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The Astrogoy astrology blog

Guides on the birth chart, the planets, the houses and the transits. Written with astronomical rigor and the tradition the Church preserved in monasteries and universities.

Swiss Ephemeris7 languagesNatural astrology · Thomas AquinasPlacidus system

Reading the sky without foretelling the future

The birth chart is an instrument of knowledge, not of divination. Thomas Aquinas fixed the distinction in the Summa Theologica (II-II, q.95): natural astrology, which observes the influence of the celestial bodies on matter and character, is lawful; judicial astrology, which claims to read free acts and destiny in the stars, is condemned. The guides in this blog belong to the first.

Each article is calculated with Swiss Ephemeris, the same database used by observatories. Positions are not estimated: they are calculated with the precision of celestial mechanics. What is done with the map — the interpretation — belongs to the order of the symbol, not of divination.

The Church preserved this knowledge during the centuries when astronomy and astrology had not yet separated. Monasteries copied the tables of Ptolemy. Medieval universities taught the Quadrivium — arithmetic, geometry, music and astronomy — as a noble discipline. Without that patient conservation, the modern birth chart would not exist.

Published guides

Two introductory guides to the birth chart. More in preparation.

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