Pierre Duhem: How the Catholic Church Destroyed Astrology and Prepared the Way for Modern Science

In the system which Maimonides sets forth we see, so to speak, the culmination of all the ideas whose development has been traced in this chapter.

We find there, first of all, the affirmation of the principle that Aristotle had already formulated with such clarity: The various parts of the universe is interconnected by a rigorous determinism and this determinism subjects the entire world of generation and corruption to the rule of celestial circulations.

We find there the corollary of that principle, namely, the definition of an astrological science which ties all changes accomplished here below to the motion of a specific planet.

We see there the preponderant role which that astrology attributes to the Moon as a rule of water and humid matter.  The moon forces them to grow and decrease with her.  The theory of tides clearly proves the reality of this lunar action and, through it, of all influence emanating from the celestial bodies.

Finally, we hear stated that the very slow changes on earth are tied to the almost imperceptibly slow motion of the fixed stars whose revolution measures the Great Year.

To that system all the disciples of Greek philosophy—Peripatetics, Stoics, Neoplatonists—have contributed.  To that system Abu Masar offered the homage of the Arabs.  The most illustrious rabbis, from Philo of Alexandria to Maimonides accepted that system.

Christianity was needed to condemn that system as a monstruous supersitition and to throw it overboard….

Hardly anxious to explore in detail the works of Greek astronomers, the bishop of Hippo and with him, undoubtedly, the great majority of the Church Fathers, did not know how to separate, in a precise manner, the hypotheses of the astronomers from the astrologer’s superstitions.  The former were confusedly included in the disapprovals accorded to the latter….

Let us not therefore search in the writings of the Church Fathers for the traces of a meticulously and sophisticatedly treated science.  We assuredly cannot find them there at all.

Let us not, however, neglect the little they said about physics and astronomy.

First of all, their teachings on this topic are the first seeds from which the cosmology of the Christian Middle Ages would slowly and gradually develop.

Also, and above all, the Church Fathers hit, and did so in the name of the Christian Creed, the pagan philosophers on points which, today, we consider more metaphysical than physical but where actually lie the cornerstones of the physics of Antiquity: such are the theory of an eternal prime matter, the belief in the stars’ domination over sublunary things and in the periodic life of a cosmos subject to the rhythm of the Great Year.  By destroying through these attacks the cosmologies of peripatetism, of Stoicism, and of Neoplatonism, the Fathers of the Church clearly prepare the way for modern science.

Source: Pierre Duhem, Le systeme du monde… Tome II.  La cosmologie hellenique (1914), pp. 390, 4087-408 (1914-1).  In Scientist and Catholic: An Essay on Pierre Duhem by  Stanley L. Jaki (Christendom, Front Royal, VA, 1991), pp. 256-257.