Astrology, Astral Influences, and Occult Properties in the Thirteenth and Fourteenth Centuries

ASTROLOGY, ASTRAL INFLUENCES, AND OCCULT PROPERTIES IN THE THIRTEENTH AND FOURTEENTH CENTURIES By NICOLAS WEILL-PAROT The notion of natural "occult" is usually viewed by modern scholars as a tautological way of dealing with phenomena for which there was no current explanation. Consider how Molière mocks scholastic medicine in the "Interm ède" of Le malade imaginaire when he gives the Bachelierus a silly answer to the question of why opium makes one sleep: "quia est in eo virtus dormitiva / Cujus est natura / Sensus assoupire." Opium makes one sleep because it has a sleep-inducing power; its nature is to make "the senses drowsy." The words of Molière's Bachelierus are strikingly similar to what Augustine writes in the City of God (21, 7) concerning natural things that are endowed with extraordinary properties: "So for the other cases, irksome to rehearse, in which an unusual power seems to be present contrary to nature, yet no other explanation is given except to say such is their nature. No doubt their explanation is short, and still it answers enough."2 Obviously, however, the very meaning of Augustine's statement is just the opposite of Molière's. In Augustine's view, the answer is "short," because the real and only cause is God himself; nature is only an illusory cause. For Molière, the Bachelierus's answer is inane, because it seems to give a scientific explanation but in fact says nothing and certainly does not look for the true natural causes. But between Augustine and Molière there was scholastic science, in which the 1 A study of this section can be found in Keith Hutchison, "Dormitive Virtues, Scholastic Qualities, and the New Philosophies," History of Science 29 (1991): 245-78, esp. 245. 1 wish to thank Gad Freudenthal, Danielle Jacquart, and Barbara Obrist for their readings and advice, and Azélina Jaboulet-Vercherre and Katelyn Mesler for their English emendations. The author is Maître de conférences in Medieval History at Université Paris 8 and Junior fellow of the Institut universitaire de France. This article was previously a presentation given at a workshop held by the team CHSPAM (UMR 7219) of the CNRS and organized by Gad Freudenthal: "L'astrologie au Moyen Âge: Traditions arabe, hébraïque, latine" (Paris, 8 November 2008). 2 Augustine, De civitate dei 21, 7, ed. Bernhard Dombart and Alfons Kalb with Johannes Divjak, 5th ed. (Stuttgart, 1993), 501: "quibus licet vis insólita contra naturam inesse videatur, alia tamen de illis non redditur ratio, nisi ut dicatur hanc eorum esse naturam. Brevis sane ista ratio, fateor, sufficiensque responsio." English translation: Augustine, The City of God against the Pagans, vol. 7, Books XXI-XXII, trans. William M. Green (Cambridge , MA, 1972), 43. 202TRADITIO virtus occulta was not a mere tautological statement but a real explanation based on a coherent conception of nature. From the thirteenth century onwards, the prominent framework of scholastic philosophy and science was an Aristotelian, or better an Aristotelizing, one. As is well known, the Aristotelian cosmos was divided into a superlunary world, where, beneath the sphere of the so-called fixed stars, seven spheres were carrying and moving the seven planets respectively, and a sublunary world, that of the four elements, i.e., fire, air, water, and earth, undergoing continuous generation and corruption — each of them being defined through a couple of qualities (earth being cold and dry, water cold and moist, air warm and moist, and fire warm and dry). According to scholastic medicine and natural philosophy (from the twelfth and thirteenth centuries onwards), the natural operations produced by the inferior bodies could generally be reduced to the action of primary qualities or to those qualities deriving directly from their mixing (i.e., complexion). These qualities could be called "manifest," since they were obviously perceived by a man when he was looking for them: a warm body, for instance, reveals its warm quality to the man who touches it. But certain natural phenomena could not be explained by primary qualities or the mixing of them, as in the case of the lodestone's attraction of iron, since a man who touches a magnet cannot perceive its attractive power...