By the time the Vatican developed into the centre of the Catholic Church around 500CE with the building of St. Peter’s Basilica the Earth was known to be a sphere. At no time has the flat earth concept been a teaching of the Catholic, or the later Protestant faiths. Students going to any of the universities later established under the church were taught that the Earth was a globe.
Historian Jeffrey Burrell surveyed some 10,000 relevant documents relating to the shape of the Earth, of which only two defended a flat Earth and three were ambiguous.
There were two main outliers, the 3rd Century Christian apologist Lactantius, for whom anything smacking of Pagan beliefs was wrong and the spherical Earth was a pagan idea, and Comas Indicopleustes, a sixth century Byzantine monk whose work appears to have gone unread for two centuries. Neither were influential in the cosmography of the Catholic Church.
Lactantius was so far out on the periphery of church thought that when Copernicus wrote his treatise on heliocentricity – the Earth orbiting the Sun – he likened Lactantius’s views on the flat Earth to the belief that the Earth was the centre of the universe because he knew the views of Lactanius had been rejected and that to reject the heliocentric view in the face of the evidence he provided was just as irrational as Lactantius.
Islamic scholars such as Ibn Hazm, Al Biruni, and al-Farghani, basing their thinking on Persian, Indian, Greek and Roman teachings and expanding upon it, accepted that the Earth was a sphere.
Ibn Hazm provides one the few claims that belief in a flat Earth was common: “The Earth is spherical, despite what is popularly believed”. Significantly, he worked from Cordoba in Spain in the 10th century, one of several centres of learning in Spain, including Salamanca and Granada during the period of Moorish control over the Iberian peninsula.
David McNeill, Map Librarian of the Royal Geographical Society says “Sadly, unlike the present day when an increasing proportion of the ‘general population’ possess the means to record and broadcast their thoughts, prejudices and beliefs at the press of a button (thus creating a vast treasure trove of material for future researchers interested in collective understanding) no comparable data is available in any quantity for the past couple of millennia, so I am afraid we are unlikely to reach any definitive conclusions on how the general public of the time felt about any particular topic.
“I think it is disingenuous, however, to separate the ‘educated’ and the clergy. For most of human history the two have been pretty much synonymous and the survival and dissemination of much Western knowledge throughout the medieval age is inextricably linked to the preservation and copying work of religious orders. For example, the oldest surviving copy of Ptolemy’s ‘Geography’, originally a second century work containing, amongst other things, a description of the shape of the earth using spherical trigonometry and elementary geodesy, is a twelfth century copy held in the Vatican Library. This work was translated and studied by scholars, many of whom were also priests, and it was the basis for the first printed world atlases produced in the fifteenth century, so it would appear that the church did not have a problem with any of its personnel or customers having access to this knowledge. It would also seem plausible that for most of the medieval period in any given rural area the most ‘educated’ person and the local priest were likely to have been one and the same, so if any of the local population were curious enough to ask they may well have received a reasonably accurate answer.”
So, when Columbus and Magellan set off on their explorations they did so armed with the wealth of knowledge and evidence that the Earth was a globe and those who approved, promoted and financed their expeditions knew it to be so.
Certainly, the idea of the Earth as a globe was not global. China clung to the flat Earth until about the 16th or 17th centuries and the arrival of Jesuit missionaries. Despite the Silk Road that traced its way from Southeast Asia, through China itself, the Middle East, and on to Europe there seems to have been little flow of thought in the other direction. Or, at least, not thought that was acceptable to the Imperial Court.
The idea of a spherical Earth did not implant itself in Southeast Asia until the 19th Century.
In the Middle Ages in the West the spherical nature of the Earth was an accepted fact. The arguments centred on matters unrelated to its shape.
A big issue was whether the universe rotated around the Earth, Geocentrism, or the Earth moved around the Sun, Heliocentrism. The objections to heliocentrism were not solely theological, eminent astronomers like Tycho Brahe who held that the phenomenae one would expect from a heliocentric cosmology had not been observed. Today, relativity and concepts such as frames of reference, might suggest that both were right for different reasons.
More important for exploration was the size of the Earth and whether it was possible for a ship to sail from Europe to Asia across the vast ocean without the opportunity to renew provisions such as food and water for the time it would take. In addition, it would mean sailing uphill, said some critics, and at one point in his third voyage Columbus thought he was sailing uphill on a pear-shaped Earth. Columbus got around this objection by cherrypicking his data and fiddling his figures to argue that the Earth was far smaller than it actually was. Magellan, too, thought the Earth was far smaller and almost ran out of food by the time he ended up off the islands of Homonhon and Sulu-an in Samar.
Neither when Columbus returned, nor when the Magellan-Elcano Armada de Maluccas arrived in Seville did anyone cry the medieval equivalent of “quid mirum! Terram rotundam esse videtur!”, or even remarked upon its sphericity. Nobody seems to have been surprised.
Also, there was the question of the Antipodes, the other side of the planet. They could not be inhabited because anyone who lived there could not be descended from Adam and Eve, and, of course, any inhabitants would necessarily have to live upside down, and since any land could not be inhabited there was no need for an almighty deity to put any land there anyway. Or it would be too hot for human habitation.
World maps, Mappamundi, of the period, in particular the orbis terrarum maps which follow the description of the Earth in the writings of St. Isidore of Seville in the 7th century. These show a circle, O, trisected by a T, into the three continents of Asia, Europe and Africa, separated by the Mediterranean, the Nile, and the Don in Russia.
St. Isidore’s writings are far from clear. At times he appears to consider the Earth as a flat disc, at others as a sphere. He did, however, depict only the known inhabited parts of the Earth, the Northern hemisphere and there was no need to depicted the Southern hemisphere, or antipodes because nobody lived there and nobody could pass the Equator because it was too hot to live there.
Basically, the T in O maps, only depicted the Northern, known hemisphere, as did other maps of the period, on a flat surface not because the Earth was flat but because the pages of a book, the surfaces of the walls on which representations of the map, were themselves flat.
The term “Dark Ages’ was invented in 1340 by Petrarch, who’s modernist writings kicked off the Italian Renaissance. It is not a term used by many modern scholars because the so-called ‘Dark Ages’ really were not that ‘Dark’ and certainly the notion that the Flat Earth was the prevailing belief among those of importance or in power is simply nonsense.
In fact, it was an invention of intellectually dishonest but eminent writers of the 19th century with the help of an overly imaginative psuedo-biography of Columbus, as we shall see in the next episode.