The Unmaking of the Medieval Christian Cosmos, 1500-1760: From Solid Heavens to Boundless AEther and Comets, Popular Culture, and the Birth of Modern Cosmology. (Reviews).

W. G. L. Randles. The Unmaking of the Medieval Christian Cosmos, 1500-1760: From Solid Heavens to Boundless AEther

Aldershot, UK: Ashgare, 1999. xvi + 274 pp. $99.95. ISBN: 1-84014-624-9.

Sara Schechner Genuth. Comets, Popular Culture, and the Birth of Modern Cosmology

Princeton: Princeton University Press, 1997. xvi + 365 pp. $60. (cl), $18.95 (pbk). ISBN: 0-691-01150-8 (cl), 0-691-00925-2 (pbk).

Tabitta Van Nouhuys. The Age of the Two-Faced Janus: The Comets of 1577 and 1618 and the Decline of the Aristotelian World View in the Netherlands (Brill's Studies in Intellectual History, 89) Leiden: Brill, 1998. xii + 603 pp. $162. ISBN: 90-04-11204-9.

In The Unmaking of the Medieval Christian Cosmos, W. G. L. Randles contextualizes the evolution of Early Modern cosmological ideas in a fresh and thoughtful manner. He does not begin as, say, a historian of science might, for he does not focus on the ways in which a dominant Aristotelian universe succumbed to celestial observations of comets and novae. Nor does he focus on post-Galilean telescopic astronomy or the development of a mathematical physics with Newton. Certainly the author discusses these important issues, but since his focus lies on a cultural level, he does not stress quintessential scientific criteria such as observation and measurement. Randles deals with the realm of belief.

In order to discuss the dissolution of the Christian cosmos, the author begins with a careful presentation of early-Christian views of the cosmos. The author has found a rich source in the hexaemeral literature produced in the Middle Ages and argues that these sources contributed contradictory but fruitful cosmic models to later thinkers. Randles argues that, to a large extent, the dissolution of the medieval cosmos begins in the Renaissance with the application of humanist philological tools to the hexaemeral literature. For example, the author exemplifies the contemporary focus on the Hebrew word 'rakiah' (spread-outedness) in the book of Genesis. This word had been translated as 'firmament' in the Vulgate Bible, giving the sense of a solid structure which supported the cosmos. The Hebrew 'rakiah' lacked that meaning, however, and suggested to many Renaissance theologians that the Aristotelian framework that supported the medieval Christian cosmos was flawed. They began to turn instead to competing models t hat appeared in the patristic writings.

The middle chapters of the book deal more specifically with thinkers who played a larger role in the Scientific Revolution. Most important for Randles are the contributions of Jean, Pena, Tycho Brahe and Christoph Rothmann. The author makes clear that these men operated in a theological atmosphere wherein the nature of the cosmos was hotly debated. The consequences of their optical theories and careful observations supported the position that the heavens were fluid. The author also examines the thought of Jesuits such as Robert Bellarmine and Christoph Clavius and important thinkers in the history of philosophy and science, namely Giordano Bruno, Francesco Patrizzi, Rene' Descartes, Pierre Gassendi, and Isaac Newton. His main goal here is to trace the influence of these new ideas, looking at extremes of reaction from staunch defenders of Aristotelianism to the reception of new ideas among the most heterodox of thinkers in the seventeenth century.

The last chapters deal with spread of the new ideas in the textbook tradition of the seventeenth and eighteenth centuries. He demonstrates that the concept of a fluid heavens was slow to migrate from the thought of theologians and philosophers to the mind-set of the learned Catholic elite of Europe. In the seventeenth century, the resistance to the widespread acceptance of the new ideas centered around the theological concept of the Empyrean. This, the author argues, remained the last bastion of the finite universe maintained in the Medieval Cosmos. By the eighteenth century, even this last concept disappeared, making it possible for the Church to lift the ban on teaching Copernicanism and bringing the medieval cosmos to an end.

The points of contact between the history of science and the history of popular culture have received scant attention from scholars. Where these contacts have received attention, particularly in the history of medicine, they have proved useful in detailing the influences linking the learned culture of Europe with that of the largely illiterate culture of the masses. Sara Schechner Genuth in her Comets, Popular Culture, and the Birth of Modern Cosmology has, gone far to show not only that such links existed, but also to show in particular that these links could prove fruitful in the profound sense of shaping the structure and content of modern science.

The author divides her analysis into four main parts that are unified on a thematic level. The first deals primarily with the divinatory and religious aspects of comet lore in western culture from antiquity to early modern times. Comets played important roles, for example, as portents of natural and political upheavals, and much depended on their attributes of shape, color, direction of their tales, and their conjunctions with zodiacal signs. In the Christian culture of Europe, comets often possessed messianic messages that became more or less acute depending on religious circumstances.

Part two considers new attitudes toward nature and the decline of cometary divination. With the recovery and assimilation of ancient science, intellectuals increasingly viewed comets as part of the natural world, not necessarily possessing hidden meanings for humanity. Key elements in this development included the later-medieval assimilation of Aristotelian natural philosophy, which viewed comets as atmospheric phenomena with natural causes. The author also discusses important developments such as new astronomical and epistemological ideas and the contribution of social changes that contributed to the decline of the view of comets as celestial messengers among the learned elite.

Parts three and four focus on English science and cosmogony in the seventeenth century. The author provides an extended analysis of the thought of Isaac Newton and Edmond Halley and argues convincingly that they appropriated many aspects of traditional comet lore into the new science. Concepts such as the 'refueling' of Sun and planets by means of comets suggests a link between more traditional views and that of seventeenth-century English scientists. Lastly, the author includes interesting comments on modern forms of astronomical carastrophism, suggesting the influence of traditional comet lore as filtered through the Scientific Revolution.

The last work, Van Nouhuys' The Age of the Two-Faced Janus: The Comets of 1577 and 1618 and the Decline of the Aristotelian World View in the Netherlands, also concentrates on the subject of comets, but the focus is very different than that of Schechner Genuth. Whereas the latter is more of a synthetic approach to intellectual changes over an extended period of time, the former is an in-depth look at two particular cometary appearances and their influence on Dutch thought in the late-sixteenth and early-seventeenth centuries.

The first part of this work begins with an extended discussion of historiographical matters, continues with cometary theory and lore up to the sixteenth century, and ends with the dilemma posed to traditional cosmologies, religious and philosophical by the comet of 1577. The author not only takes the reader through familiar Aristotelian/Ptolemaic territory, but she also includes significant discussions of Stoic cosmology as well as the accommodations between philosophy and Christianity that emerged in the Middle Ages. The Renaissance also contributed to developments in cometary theory with, for example, the growing regard for precise measurement, and the spread of 'heterodox' cometary theories in the sixteenth century.

The late-sixteenth and seventeenth centuries form a watershed for Van Nou-huys. She argues that a sustained and creative 'dialogue' concerning the nature and position of comets began in antiquity and reached a 'culmination' after 1577. This dialogue continued up to and beyond 1618 as philosophers sought to understand, for example, the meaning of Tychonic observations, Copernican challenges to established theories, and Stoic notions of a fluid heaven. Whereas the comet of 1577 is often credited with initiating a revolutionary and decisive break between a monolithic Aristotelianism and the Scientific Revolution, Van Nouhuys makes a more detailed and subtle argument. She establishes that Dutch intellectuals in this period entered into a profound, and prolonged, dialogue between the ancient representatives of cosmological systems and the celestial representatives of the New Science. This dialogue centered on fundamental Aristotelian ideas, namely, the separation of the universe into sublunary and superlunary regi ons and the idea of celestial incorruptibility. Contemporary discussions regarding the location of comets and their constitution made these ideas untenable in the eyes of most Dutch thinkers. Instead, after 1577, they took the first steps toward abandoning the Aristotelian premises by "postulating intermediate zones filled with a kind of matter that partook of both celestial and terrestrial qualities" (571). The comet of 1618, which arrived soon after Galileo's telescopic discoveries, provided the Dutch with even more reason to question peripatetic principles. Consequently, the Dutch grappled with a fundamental re-evaluation of traditional tenets, which in turn forced a readjustment of their mental outlook. Hence, Van Nouhuys argues that Dutch thinkers began to reject the teratological stance towards comets that had been so prevalent since Antiquity.

The three works discussed here share a common theme. The dissolution of the Aristotelian world view was complex, profound, and lengthy. Together they reveal a rich period in cultural history. These works also suggest new paths for research. Did, for example, Dutch thinkers also appropriate traditional comet lore into their seventeenth century world views? Were other English thinkers particularly influenced by the 1577 and 1618 comets or by patristic conceptions of the universe? These authors have brought new evidence to the fore, and they have also expanded our ways of looking at that evidence. They successfully trace that rich and intricate history that tells us so much.