The Natural and the Supernatural in the Middle Ages

Attitudes to nature and the environment are fashionable topics in historical studies at present, and Robert Bartlett's book forms part of an ongoing discussion about the definition and limits of the natural world in the Middle Ages and other periods. The book originated in a series of lectures given at Queen's University Belfast in 2006, and it maintains the colloquial flavour and striking examples characteristic of an oral presentation. It explores the "debates and differences" that arose among medieval scholars, mostly writing between the 9th and the 13th centuries, when they discussed the boundaries of the natural world and its relationship to the supernatural.

The first chapter discusses the definitions of "natural" offered by a range of medieval intellectuals, and describes how the term "supernatural" was coined in the 13th century to categorise phenomena seen as above or beyond nature. It also addresses the question of whether this period witnessed a "contraction of the sphere of the supernatural": that is, did thinkers from the 12th century onwards offer more naturalistic, rationalistic explanations of the world than had their predecessors? Bartlett thinks that they did, but warns us against seeing this as a simple history of progress towards modern science, pointing out that the Early Modern period, often characterised as the age of rationality, was also the age of witch-hunting. The second chapter examines views of the Earth and its geography, focusing on contemporary debates about whether there were habitable lands in the southern hemisphere, and about the cause and meaning of eclipses. These debates illustrate the diversity of views that existed in the Middle Ages concerning how far purely physical explanations could account for the nature of the universe.

Bartlett goes on to focus on some of the wondrous creatures believed to inhabit the world: angels and demons, dog-headed people and nocturnal, dangerous female creatures called strigae. He uses medieval discussions of these beings to illuminate a variety of issues, including ideas about witchcraft; the difference between humans and animals; and the nature and extent of medieval scepticism about the supernatural. More broadly, he asks how historians should analyse medieval beliefs they do not share.

The final chapter explores how some of these issues are played out in the writings of one 13th-century thinker, Roger Bacon.

Bacon was interested in the power latent in the natural world, arguing that science could devise weapons for use against the Antichrist (who would himself be a scientist) and also contending that many so-called "magical" phenomena, such as the evil eye, in fact had natural explanations.

Bartlett does not claim to offer a comprehensive discussion of any of these topics. Instead he presents a selection of case studies that illustrate the conceptual problems that medieval writers faced when they thought about the natural and supernatural worlds. This approach sometimes raises more questions than it answers, but it does highlight the diversity of medieval views of these issues and the seriousness with which intellectuals tackled problems that seem trivial to modern readers - although, as Bartlett points out, the classic example, namely the question of how many angels can dance on the head of a pin, seems not to have been asked in the Middle Ages at all. Overall, this is an engaging and readable book that presents much food for thought, both for medievalists and for non-specialist readers.