The Copernican Question: Prognostication, Skepticism, and Celestial Order

1. The Literature of the Heavens and the Science of the Stars

25 1 The Literature of the Heavens and the Science of the Stars prinTinG, planeTary Theory, and The Genres of foreCasT In the fifteenth century, a vast and complex literature described, explained, and invoked the motions of the heavens and their influences on the Earth. From the 1470s onward, the learning of the heavens, much of it inherited from the ancient and medieval worlds, began to acquire a new sort of accessibility as it was reproduced in the medium of print. This chapter describes the broad contours of that literature and its various classifications. It shows how those categories evolved, how it worked as a body of knowledge, and the peculiar forms that it took in the sixteenth century. This corpus of writings—rather than an exclusive and autonomous stream of planetary theory—constituted the foundational categories of the intellectual world in which Copernicus was educated at Krakow and Bologna in the 1490s and in which his work took form and was later evaluated. Interest in astrological prognosticating had begun to catch on in the Latin West as far back as the twelfth century, with the arrival of sophisticated Arabic astrological writings. Among the most influential of such works was the Great Introduction to Astrology of Albumasar (Abu’Mashar ), which emphasized the preeminent effects of great planetary conjunctions.1 Soon, a good many medieval practitioners were attracted by the prospect of using the heavens in medical prognosis as well as retrospective diagnosis. The popular “zodiac man,” representations of which abounded by the fourteenth century, mapped signs of the zodiac onto the body parts that they ruled: it assisted surgeons in deciding when to bleed the patient and guided physicians in prescribing a diet that would counteract a specific disease.2 The Black Death (or bubonic plague) of 1347–51, which killed one-quarter to one-third of Europe’s inhabitants, greatly accelerated a sense of loss of social control and, with it, augmented the special credibility of Albumasarian causal explanations grounded in the power of planetary conjunctions.3 In the last decade of the fifteenth century, another new and frightening disease entity appeared, accompanying the massive movement of French armies into Italy. It too killed, but first by attacking the genitals. Was this “French disease,” as many non-Frenchmen called it, caused by a conjunction of Saturn and Jupiter on 25 November 1484? Was it, soon afterward, augmented by a “horrible” solar eclipse on 25 March 1485? Or did God act directly, without need of celestial influence, to punish men for their sins? Whatever the preferred explanation, “astrology had come to stay,” as Olaf Pedersen has aptly observed , “and many scholars came to regard astronomy principally as a theoretical introduction to astrological practice.”4 It is difficult to generalize with confidence about the full range of astrological works that were composed before the era of print. The extant remains of the considerable library of Simon de Phares, astrologer to the French king Charles vIII, 26 CoperniCus’s spaCe of possibiliTies ready classified prognostications into two kinds— those concerning “whole races, countries and cities ” (general) and those relating to individuals (specific).6 Print technology made possible the first kind in a way that had not previously existed. Just over twenty years after Gutenberg published the first book in the West, an almanac for the year 1448, the urban or regional forecast became may be a useful indicator; it was principally a collection devoted to the destinies of individuals.5 Insofar as medical astrology concerned individual patients, that would partly account for such a focus. However, the arrival of syphilis with Charles’s marauding armies spawned a genre of writing about the new plague that applied not just to individuals but to groups. Ptolemy had al0 20 40 60 80 100 120 140 1471–1475 1476–1480 1481–1485 1486–1490 1491–1495 1496–1500 1501–1505 1506–1510 1511–1515 1516–1520 1521–1525 1526–1530 1531–1535 1536–1540 1541–1545 1546–1550 1551–1555 1556–1560 1561–1565 1566–1570 1571–1575 1576–1580 1581–1585 1586–1590 1591–1595 1596–1600 1601–1605 1606–1610 1611–1615 1616–1620 1621–1625 1626–1630 Prognostications Theoretical Astronomy 2. Astrological prognostications compared with works of theoretical astronomy published in the German lands, 1470–1630. Based on zinner 1941, 73. The liTeraTure of The heavens 27 items, illustrates this contention...