Flat Earth


The flat Earth model is an archaic conception of Earth's shape as a plane or disk. Many ancient cultures subscribed to a flat Earth cosmography, including Greece until the classical period, the Bronze Age and Iron Age civilizations of the Near East until the Hellenistic period, India until the Gupta period, and China until the 17th century.
The idea of a spherical Earth appeared in ancient Greek philosophy with Pythagoras, although most pre-Socratics retained the flat Earth model. In the early 4th century BC Plato wrote about a spherical Earth, and by about 330 BC his former student Aristotle provided evidence for the spherical shape of the Earth on empirical grounds. Knowledge of the spherical Earth gradually began to spread beyond the Hellenistic world from then on.
Despite the scientific fact of Earth's sphericity, pseudoscientific flat Earth conspiracy theories are espoused by modern flat Earth societies and, increasingly, by unaffiliated individuals using social media.

History

Belief in flat Earth

West Asia

In early Egyptian and Mesopotamian thought, the world was portrayed as a disk floating in the ocean. A similar model is found in the Homeric account from the 8th century BC in which "Okeanos, the personified body of water surrounding the circular surface of the Earth, is the begetter of all life and possibly of all gods."
The Pyramid Texts and Coffin Texts of ancient Egypt show a similar cosmography; Nun encircled nbwt.
The Israelites also imagined the Earth to be a disc floating on water with an arched firmament above it that separated the Earth from the heavens. The sky was a solid dome with the Sun, Moon, planets, and stars embedded in it.

Greece

Poets
Both Homer and Hesiod described a disc cosmography on the Shield of Achilles.
This poetic tradition of an Earth-encircling sea and a disc also appears in Stasinus of Cyprus, Mimnermus, Aeschylus, and Apollonius Rhodius.
Homer's description of the disc cosmography on the shield of Achilles with the encircling ocean is repeated far later in Quintus Smyrnaeus' Posthomerica, which continues the narration of the Trojan War.
Philosophers
Several pre-Socratic philosophers believed that the world was flat: Thales according to several sources, and Leucippus and Democritus according to Aristotle.
Thales thought that the Earth floated in water like a log. It has been argued, however, that Thales actually believed in a round Earth. Anaximander believed that the Earth was a short cylinder with a flat, circular top that remained stable because it was the same distance from all things. Anaximenes of Miletus believed that "the Earth is flat and rides on air; in the same way the Sun and the Moon and the other heavenly bodies, which are all fiery, ride the air because of their flatness". Xenophanes of Colophon thought that the Earth was flat, with its upper side touching the air, and the lower side extending without limit.
Belief in a flat Earth continued into the 5th century BC. Anaxagoras agreed that the Earth was flat, and his pupil Archelaus believed that the flat Earth was depressed in the middle like a saucer, to allow for the fact that the Sun does not rise and set at the same time for everyone.
Historians
believed that the Earth was flat and surrounded by water. Herodotus in his Histories ridiculed the belief that water encircled the world, yet most classicists agree that he still believed Earth was flat because of his descriptions of literal "ends" or "edges" of the Earth.

Europe

The ancient Norse and Germanic peoples believed in a flat Earth cosmography with the Earth surrounded by an ocean, with the axis mundi, a world tree, or pillar in the centre. In the world-encircling ocean sat a snake called Jormungandr. The Norse creation account preserved in Gylfaginning states that during the creation of the Earth, an impassable sea was placed around it:
The late Norse Konungs skuggsjá, on the other hand, explains Earth's shape as a sphere:

East Asia

In ancient China, the prevailing belief was that the Earth was flat and square, while the heavens were round, an assumption virtually unquestioned until the introduction of European astronomy in the 17th century. The English sinologist Cullen emphasizes the point that there was no concept of a round Earth in ancient Chinese astronomy:
The model of an egg was often used by Chinese astronomers such as Zhang Heng to describe the heavens as spherical:
This analogy with a curved egg led some modern historians, notably Joseph Needham, to conjecture that Chinese astronomers were, after all, aware of the Earth's sphericity. The egg reference, however, was rather meant to clarify the relative position of the flat Earth to the heavens:
Further examples cited by Needham supposed to demonstrate dissenting voices from the ancient Chinese consensus actually refer without exception to the Earth being square, not to it being flat. Accordingly, the 13th-century scholar Li Ye, who argued that the movements of the round heaven would be hindered by a square Earth, did not advocate a spherical Earth, but rather that its edge should be rounded off so as to be circular. However, Needham disagrees, affirming that Li Ye believed the Earth to be spherical, similar in shape to the heavens but much smaller. This was preconceived by the 4th-century scholar Yu Xi, who argued for the infinity of outer space surrounding the Earth and that the latter could be either square or round, in accordance to the shape of the heavens. When Chinese geographers of the 17th century, influenced by European cartography and astronomy, showed the Earth as a sphere that could be circumnavigated by sailing around the globe, they did so with formulaic terminology previously used by Zhang Heng to describe the spherical shape of the Sun and Moon.
As noted in the book Huainanzi, in the 2nd century BC, Chinese astronomers effectively inverted Eratosthenes' calculation of the curvature of the Earth to calculate the height of the Sun above the Earth. By assuming the Earth was flat, they arrived at a distance of . The Zhoubi Suanjing also discusses how to determine the distance of the Sun by measuring the length of noontime shadows at different latitudes, a method similar to Eratosthenes' measurement of the circumference of the Earth, but the Zhoubi Suanjing assumes that the Earth is flat.

Alternate or mixed theories

Greece: spherical Earth

in the 6th century BC and Parmenides in the 5th century stated that the Earth is spherical, and this view spread rapidly in the Greek world. Around 330 BC, Aristotle maintained on the basis of physical theory and observational evidence that the Earth was spherical, and reported an estimate of its circumference. The Earth's circumference was first determined around 240 BC by Eratosthenes. By the 2nd century AD, Ptolemy had derived his maps from a globe and developed the system of latitude, longitude, and climes. His Almagest was written in Greek and only translated into Latin in the 11th century from Arabic translations.
Lucretius opposed the concept of a spherical Earth, because he considered that an infinite universe had no center towards which heavy bodies would tend. Thus, he thought the idea of animals walking around topsy-turvy under the Earth was absurd. By the 1st century AD, Pliny the Elder was in a position to claim that everyone agreed on the spherical shape of Earth, though disputes continued regarding the nature of the antipodes, and how it is possible to keep the ocean in a curved shape.

South Asia

The Vedic texts depict the cosmos in many ways. One of the earliest Indian cosmological texts picture the Earth as one of a stack of flat disks.
In the Vedic texts, Dyaus and Prithvi are compared to wheels on an axle, yielding a flat model. They are also described as bowls or leather bags, yielding a concave model. According to Macdonell: "the conception of the Earth being a disc surrounded by an ocean does not appear in the Samhitas. But it was naturally regarded as circular, being compared with a wheel and expressly called circular in the Shatapatha Brahmana."
By about the 5th century CE, the siddhanta astronomy texts of South Asia, particularly of Aryabhata, assume a spherical Earth as they develop mathematical methods for quantitative astronomy for calendar and time keeping.
The medieval Indian texts called the Puranas describe the Earth as a flat-bottomed, circular disk with concentric oceans and continents. This general scheme is present not only in the Hindu cosmologies, but also in Buddhist and Jain cosmologies of South Asia. However, some Puranas include other models. For example, the fifth canto of the Bhagavata Purana, includes sections that describe the Earth both as flat and spherical.

Early Christian Church

During the early period of the Christian Church, the spherical view continued to be widely held, with some notable exceptions.
Athenagoras, an eastern Christian writing around the year 175 CE, said that the Earth was spherical. Methodius, an eastern Christian writing against "the theory of the Chaldeans and the Egyptians" said: "Let us first lay bare... the theory of the Chaldeans and the Egyptians. They say that the circumference of the universe is likened to the turnings of a well-rounded globe, the Earth being a central point. They say that since its outline is spherical,... the Earth should be the center of the universe, around which the heaven is whirling." Lactantius, a western Christian writer and advisor to the first Christian Roman Emperor, Constantine, writing sometime between 304–313 CE, ridiculed the notion of antipodes and the philosophers who fancied that "the universe is round like a ball. They also thought that heaven revolves in accordance with the motion of the heavenly bodies.... For that reason, they constructed brass globes, as though after the figure of the universe." Arnobius, another eastern Christian writing sometime around 305 CE, described the round Earth: "In the first place, indeed, the world itself is neither right nor left. It has neither upper nor lower regions, nor front nor back. For whatever is round and bounded on every side by the circumference of a solid sphere, has no beginning or end..."
The influential theologian and philosopher Saint Augustine, one of the four Great Church Fathers of the Western Church, similarly objected to the "fable" of antipodes:
Some historians do not view Augustine's scriptural commentaries as endorsing any particular cosmological model, but the view that Augustine shared the common view of his contemporaries that the Earth is spherical, in line with his endorsement of science in De Genesi ad litteram, has been challenged:
Diodorus of Tarsus, a leading figure in the School of Antioch and mentor of John Chrysostom, may have argued for a flat Earth; however, Diodorus' opinion on the matter is known only from a later criticism. Chrysostom, one of the four Great Church Fathers of the Eastern Church and Archbishop of Constantinople, explicitly espoused the idea, based on scripture, that the Earth floats miraculously on the water beneath the firmament. Athanasius the Great, Church Father and Patriarch of Alexandria, expressed a similar view in Against the Heathen.
Christian Topography by the Alexandrian monk Cosmas Indicopleustes, who had traveled as far as Sri Lanka and the source of the Blue Nile, is now widely considered the most valuable geographical document of the early medieval age, although it received relatively little attention from contemporaries. In it, the author repeatedly expounds the doctrine that the universe consists of only two places, the Earth below the firmament and heaven above it. Carefully drawing on arguments from scripture, he describes the Earth as a rectangle, 400 days' journey long by 200 wide, surrounded by four oceans and enclosed by four massive walls which support the firmament. The spherical Earth theory is contemptuously dismissed as "pagan".
Severian, Bishop of Gabala, wrote that the Earth is flat and the Sun does not pass under it in the night, but "travels through the northern parts as if hidden by a wall". Basil of Caesarea argued that the matter was theologically irrelevant.

Europe: Early Middle Ages

Early medieval Christian writers in the early Middle Ages felt little urge to assume flatness of the Earth, though they had fuzzy impressions of the writings of Ptolemy and Aristotle, relying more on Pliny.
With the end of the Western Roman Empire, Western Europe entered the Middle Ages with great difficulties that affected the continent's intellectual production. Most scientific treatises of classical antiquity were unavailable, leaving only simplified summaries and compilations. In contrast, the Eastern Roman Empire did not fall, and it preserved the learning. Still, many textbooks of the Early Middle Ages supported the sphericity of the Earth in the western part of Europe.
representing the inhabited world as described by Isidore of Seville in his Etymologiae
Europe's view of the shape of the Earth in Late Antiquity and the Early Middle Ages may be best expressed by the writings of early Christian scholars:
Bishop Isidore of Seville taught in his widely read encyclopedia, the Etymologies, diverse views such as that the Earth "resembles a wheel" resembling Anaximander in language and the map that he provided. This was widely interpreted as referring to a disc-shaped Earth. An illustration from Isidore's De Natura Rerum shows the five zones of the Earth as adjacent circles. Some have concluded that he thought the Arctic and Antarctic zones were adjacent to each other. He did not admit the possibility of antipodes, which he took to mean people dwelling on the opposite side of the Earth, considering them legendary and noting that there was no evidence for their existence. Isidore's T and O map, which was seen as representing a small part of a spherical Earth, continued to be used by authors through the Middle Ages, e.g. the 9th-century bishop Rabanus Maurus, who compared the habitable part of the northern hemisphere with a wheel. At the same time, Isidore's works also gave the views of sphericity, for example, in chapter 28 of De Natura Rerum, Isidore claims that the Sun orbits the Earth and illuminates the other side when it is night on this side. See French translation of De Natura Rerum. In his other work Etymologies, there are also affirmations that the sphere of the sky has Earth in its center and the sky being equally distant on all sides. Other researchers have argued these points as well. "The work remained unsurpassed until the thirteenth century and was regarded as the summit of all knowledge. It became an essential part of European medieval culture. Soon after the invention of typography it appeared many times in print." However, "The Scholastics – later medieval philosophers, theologians, and scientists – were helped by the Arabic translators and commentaries, but they hardly needed to struggle against a flat-Earth legacy from the early middle ages. Early medieval writers often had fuzzy and imprecise impressions of both Ptolemy and Aristotle and relied more on Pliny, but they felt, little urge to assume flatness."
St Vergilius of Salzburg, in the middle of the 8th century, discussed or taught some geographical or cosmographical ideas that St Boniface found sufficiently objectionable that he complained about them to Pope Zachary. The only surviving record of the incident is contained in Zachary's reply, dated 748, where he wrote:
Some authorities have suggested that the sphericity of the Earth was among the aspects of Vergilius's teachings that Boniface and Zachary considered objectionable. Others have considered this unlikely, and take the wording of Zachary's response to indicate at most an objection to belief in the existence of humans living in the antipodes. In any case, there is no record of any further action having been taken against Vergilius. He was later appointed bishop of Salzburg and was canonised in the 13th century.
A possible non-literary but graphic indication that people in the Middle Ages believed that the Earth was a sphere is the use of the orb in the regalia of many kingdoms and of the Holy Roman Empire. It is attested from the time of the Christian late-Roman emperor Theodosius II throughout the Middle Ages; the Reichsapfel was used in 1191 at the coronation of emperor Henry VI. However the word orbis means "circle", and there is no record of a globe as a representation of the Earth since ancient times in the west until that of Martin Behaim in 1492. Additionally it could well be a representation of the entire "world" or cosmos.
A recent study of medieval concepts of the sphericity of the Earth noted that "since the eighth century, no cosmographer worthy of note has called into question the sphericity of the Earth". However, the work of these intellectuals may not have had significant influence on public opinion, and it is difficult to tell what the wider population may have thought of the shape of the Earth, if they considered the question at all.

Europe: Late Middle Ages

was among the earliest Christian scholars to estimate the circumference of Earth with Eratosthenes' method. St. Thomas Aquinas, the most widely taught theologian of the Middle Ages, believed in a spherical Earth; and he even took for granted his readers also knew the Earth is round. Lectures in the medieval universities commonly advanced evidence in favor of the idea that the Earth was a sphere.
in a 14th-century copy of L'Image du monde
Tattersall shows that in many vernacular works in 12th- and 13th-century French texts the Earth was considered "round like a table" rather than "round like an apple". "In virtually all the examples quoted... from epics and from non-'historical' romances the actual form of words used suggests strongly a circle rather than a sphere", though he notes that even in these works the language is ambiguous.
Portuguese navigation down and around the coast of Africa in the latter half of the 1400s gave wide-scale observational evidence for Earth's sphericity. In these explorations, the Sun position moved more northward the further south the explorers travelled. Its position directly overhead at noon gave evidence for crossing the equator. These apparent solar motions in detail were more consistent with north–south curvature and a distant Sun, than with any flat-Earth explanation. The ultimate demonstration came when Ferdinand Magellan's expedition completed the first global circumnavigation in 1521. Antonio Pigafetta, one of the few survivors of the voyage, recorded the loss of a day in the course of the voyage, giving evidence for east–west curvature.

Middle East: Islamic scholars

The Abbasid Caliphate saw a great flowering of astronomy and mathematics in the 9th century AD. Muslim scholars of the past believed in a spherical Earth.
The Quran mentions that the Earth was "spread out". To this 12th-century commentary, the Tafsir al-Kabir by Fakhr al-Din al-Razi states: "If it is said: Do the words 'And the Earth We spread out' indicate that it is flat? We would respond: Yes, because the Earth, even though it is round, is an enormous sphere, and each little part of this enormous sphere, when it is looked at, appears to be flat. As that is the case, this will dispel what they mentioned of confusion. The evidence for that is the verse in which Allah says : 'And the mountains as pegs' . He called them awtaad even though these mountains may have large flat surfaces. And the same is true in this case."
The 11th-century scholar Ibn Hazm stated: "Evidence shows that the Earth is a sphere but public people say the opposite." He added: "None of those who deserve being Imams for Muslims has denied that Earth is round. And we have not received anything indicates a denial, not even a single word."
The 13th-century scholar Ibn Taymiyyah stated that the Earth is spherical and not flat. He stated that the Arabic word falak refers to that which is round. Ibn Abbas said that it is like that of a spinning wheel. The word is used in and. Unlike the previous scholars, scholar Al-Suyuti stated that the Earth is flat.

Ming Dynasty in China

A spherical terrestrial globe was introduced to Yuan-era Khanbaliq in 1267 by the Persian astronomer Jamal ad-Din, but it is not known to have made an impact on the traditional Chinese conception of the shape of the Earth. As late as 1595, an early Jesuit missionary to China, Matteo Ricci, recorded that the Ming-dynasty Chinese say: "The Earth is flat and square, and the sky is a round canopy; they did not succeed in conceiving the possibility of the antipodes." The universal belief in a flat Earth is confirmed by a contemporary Chinese encyclopedia from 1609 illustrating a flat Earth extending over the horizontal diametral plane of a spherical heaven.
In the 17th century, the idea of a spherical Earth spread in China due to the influence of the Jesuits, who held high positions as astronomers at the imperial court. Matteo Ricci, in collaboration with Chinese cartographers and translator Li Zhizao, published the Kunyu Wanguo Quantu in 1602, the first Chinese world map based on European discoveries. The astronomical and geographical treatise Gezhicao written in 1648 by Xiong Mingyu explained that the Earth was spherical, not flat or square, and could be circumnavigated.

Myth of flat-Earth prevalence

Beginning in the 19th century, a historical myth arose which held that the predominant cosmological doctrine during the Middle Ages was that the Earth was flat. An early proponent of this myth was the American writer Washington Irving, who maintained that Christopher Columbus had to overcome the opposition of churchmen to gain sponsorship for his voyage of exploration. Later significant advocates of this view were John William Draper and Andrew Dickson White, who used it as a major element in their advocacy of the thesis that there was a long-lasting and essential conflict between science and religion. Some studies of the historical connections between science and religion have demonstrated that theories of their mutual antagonism ignore examples of their mutual support.
Subsequent studies of medieval science have shown that most scholars in the Middle Ages, including those read by Christopher Columbus, maintained that the Earth was spherical.

Modern flat-Earthers

In the modern era, the pseudoscientific belief in a flat Earth has been expressed by a variety of individuals and groups:
The International Flat Earth Research Society, better known as the Flat Earth Society, was set up by Samuel Shenton in 1956, in Dover, UK, as a direct descendant of the Universal Zetetic Society. This was just before the Soviet Union launched the first artificial satellite, Sputnik; he responded: "Would sailing round the Isle of Wight prove that it were spherical? It is just the same for those satellites."
His primary aim was to reach children before they were convinced about a spherical Earth. Despite plenty of publicity, the space race eroded Shenton's support in Britain until 1967, when he started to become famous due to the Apollo program.
In 1972, Shenton's role was taken over by Charles K. Johnson, a correspondent from California, US. He incorporated the IFERS and steadily built it up to about 3000 members. He spent years examining the studies of flat- and round-Earth theories and proposed evidence of a conspiracy against flat Earth: "The idea of a spinning globe is only a conspiracy of error that Moses, Columbus, and FDR all fought..." His article was published in the magazine Science Digest in 1980. It goes on to state: "If it is a sphere, the surface of a large body of water must be curved. The Johnsons have checked the surfaces of Lake Tahoe and the Salton Sea without detecting any curvature."
The Society declined in the 1990s, following a fire at its headquarters in California and the death of Johnson in 2001. It was revived as a website in 2004 by Daniel Shenton. He believes that no one has provided proof that the world is not flat.

Internet-era resurgence

In the Internet era, the proliferation of communications technology and social-media platforms such as YouTube, Facebook and Twitter have given individuals, famous or otherwise, a platform to spread pseudo-scientific ideas and build stronger followings. The flat-Earth conjecture has flourished in this environment. Social media and the internet, furthermore, have made it easier for like-minded theorists to connect with one another and mutually reinforce their beliefs. In other words, social media has had a "levelling effect", in that experts have less sway in the public mind than they used to.
YouTube had faced criticism for allowing the spread of misinformation and conspiracy theories through its platform. In 2019, YouTube stated that it was making changes in its software to reduce the distribution of videos based on conspiracy theories including flat Earth.
Organizations skeptical of fringe beliefs have occasionally performed tests to demonstrate the local curvature of the Earth. One of these, conducted by members of the Independent Investigations Group at the Salton Sea on June 10, 2018, was attended also by supporters of a flat Earth, and the encounter between the two groups was recorded by the National Geographic Explorer. This experiment successfully demonstrated the curvature of the Earth by the disappearance over distance of boat-based and shore-based targets.

Conspiracy theory

Members of the Flat Earth Society and other flat-Earthers claim that NASA and other government agencies conspire to delude the public into believing the Earth is spherical. According to the most widely spread version of current flat-Earth theory, NASA is guarding the Antarctic ice wall that surrounds Earth. Flat-Earthers argue that NASA photoshops its satellite images, based on observations that the color of the oceans changes from image to image and that continents seem to be in different places. The publicly perpetuated image is kept up through a large-scale practice of "compartmentalization", according to which only a select number of individuals have knowledge about the truth.

Cultural references

The term flat-earth-man, used in a derogatory sense to mean anyone who holds ridiculously antiquated or impossible views, predates the more compact flat-earther. It was recorded in 1908: "Fewer votes than one would have thought possible for any human candidate, were he even a flat-earth-man." According to the Oxford English Dictionary flat-Earther's first use is in 1934 in Punch magazine: "Without being a bigoted flat-earther, perceived the nuisance... of fiddling about with globes... in order to discover the South Seas."