It is not uncommon to hear people say that the medieval church believed and taught that the earth was flat. The time period is also saddled with the label of “dark ages.” Scholarship, however, is increasing reading this view of history its last rites. In his new book, Slaying the Dragons: Destroying Myths in the History of Science and Faith, Allan Chapman offers the following on the flat earth theory.
“. . . let us be clear about one thing: no medieval scholar of any worth thought the earth was flat, and no educated person in 1492 believed that Columbus or the other early navigators would sail over the edge of it. (That seems to have been a folk myth propagated by American writers such as Washington Irving in the early nineteenth century.)
Indeed, one needs only to read the astronomical literature of the Middle Ages to realize that the spherical nature of the earth, about 6,000 or 8,000 miles across, was standard knowledge, and taught to university students from Salmanca to Prague. One has only, too, to read the first medieval astronomical treatise to be written in English, Geoffrey Chaucer’s Treatise on the Astrolabe (c. 1381), to find that the spherical, mathematical geometry of the earth the heavens was also standard knowledge. Inherited in unbroken succession from the Greeks, in fact, taught by the Venerable Bede to young monks of Jarrow Abbey in AD 710, and encapsulated in John of the Holy Wood’s (Johannes de Sacrobosco’s) Latin textbook De Sphaera Mundi (‘On the Sphere of the Earth) of c. 1240. All of these writer’s moreover, told how the round shadow of the earth that fell across the lunar disk during a lunar eclipse could only be produced by a sphere.
‘Aha!’ I hear someone say by way of contradiction, ‘What about those flat-earth maps, such as that of c. 1300 preserved in Hereford Cathedral, showing the earth as a flat disk, with water around the edge?’ These ‘Mappa Mundi’ charts, however, were symbolic maps, placing Jerusalem at their centre, with countries such as the British Isles and Spain squeezed into the edge. They were not scientific teaching or direction-finding maps so much as spiritual maps, showing Christ crucified at the centre of the world. Just compare them to a map of the London Underground. Do the straight, curved, and diagonal coloured lines on the Underground map look like London? Of course not: it is a schematic representation of local stations and their relationships with each other. Ditto for the disk-like distortions of the ‘Mappa Mundi’. On the other hand, if you look at the ‘Portolano’ navigational charts of the Middle Ages, you find the countries and regions from the Baltic to North Africa drawn to an amazing standard of geographical accuracy. From the fourteenth century onwards, if fact, Europe developed a rich tradition of scientific cartography, as our museum collections testify. (60-61)
This is an important work and it is very well written.
Allan Chapman teaches history of science in the University of Oxford. He is a Fellow of the Royal Astronomical Society and author of ten books.
Slaying the Dragons is a paperback with 256 pages and sells for $16.95.