Shape of the World I: Heaven and Earth

Steven Dutch, Professor Emeritus, Natural and Applied Sciences, University of Wisconsin - Green Bay


Some Non-Western World Concepts

The great temple at Borobudur is a metaphysical map of the Buddhist universe with multiple levels. The Aztecs had an even more complex idea of the universe with 21 levels. There were 13 levels of heaven and nine of the underworld. The earth was considered common to both sets of levels.

The Chinese viewed themselves as the center of world (as did many, possibly most other peoples). They constructed highly detailed maps, but, like most Chinese innovations, the purpose was government and administration rather than science or technology in the Western sense.

The Egyptians developed surveying and astronomy for more pragmatic purposes. A knowledge of astronomy helped predict the annual Nile flood, and surveying helped re-establish boundaries of land ownership afterward.

Are Myths "True"?

One important question we must answer is this: to what extent were myths intended to be accurate depictions of physical reality? The answer is probably very little.

Drawing a distinction between literal and non-literal interpretation is a very Western concept, reinforced especially by the printing press. Thanks to the printing press, Western culture developed concepts of individual authorship and printed facts as authoritative that simply did not exist in other times and cultures.

A very common approach to disparate beliefs in many cultures is syncretism: switching from system to system as desired without concern for overall logical consistency, or compartmentalizing beliefs so that conflicts are avoided. It's doubtful if many people in ancient times ever used the creation myths of their culture to attempt to calculate the age of the Earth, for example.

Here's an example from modern times. Present Saudi Arabia dates only from the 1920's when the Saud family subjugated rival clans. The key event was a daring raid on the capital of Riyadh (then a small town of mud brick houses) by the first King Saud. His retelling of the story became a focal point of any ceremonial occasion. The King frequently told the story with varying details. After one particularly fanciful retelling, a long-time British friend remarked "I never heard you tell it that way before." King Saud replied "I just felt like telling it that way." Clearly, in this cultural setting, the storytelling and adventure were paramount and the literal details were of secondary importance. Yet the King, who freely admitted varying and embellishing the story, and was even proud of it, would have been deeply offended if someone accused him of inconsistency or telling a falsehood. Literalism was simply not the point here.

In our culture, one of the most damaging examples of applying literalism where it was almost certainly not intended in the original culture is the recurring conflict between science and literal interpretations of the Bible.

Complicating matters is the probability that many ancient myths had at least some basis in reality while others were complete inventions or so altered in retelling that their original factual basis has been wholly obscured. It's important to distinguish between believing the entire myth and attempting to identify what its original basis might have been. See for example Cosmas' Mount Meru, Ptolemy's Mountains of the Moon, and the search for the Garden of Eden, below.

Ancient Greek Ideas of the World

The Ionians (6th century B.C.) were a culture that arose on the islands of the Aegean and the coast of Asia Minor (now Turkey). They are the first people in the Western world to have something of our experimental, pragmatic approach to science and technology, and to attempt to understand Nature in terms of natural rather than supernatural forces. Some important Ionians:

Read Chapter 7 in Sagan, The Backbone of Night, for more on the significance of the Ionians.

The prevailing ancient view of the heavens was that the planets moved in concentric spheres and were associated with the gods. Our days of the week hark back to that time. The Romans adopted the Greek gods and gave them Latin names by which we still know the planets. The table below shows the Roman gods (2nd column) and the days of the week in modern Spanish (Saturday and Sunday were named for their Christian significance.) Northern Europeans matched their gods up with the nearest Roman equivalent (3rd column) and that's where we get our days of the week.

Day of Week (Spanish) Roman Deity Norse Deity English Day of Week
Domingo (Lord's Day) Sol Sun Sunday
Lunes Luna Moon Monday
Martes Mars Tyr Tuesday
Miercoles Mercury Wodin Wednesday
Jueves Jove (Jupiter) Thor Thursday
Viernes Venus Freya Friday
Sabado (Sabbath) Saturn ---- Saturday

Claudius Ptolemy, who lived in the first half of the second century A.D., was one of the most influential of ancient scientists. Although best known for his contributions to astronomy, he also had a powerful impact on geography. He was apparently the first person to devise a sophisticated map projection that represented latitude and longitude by curved lines.

Deep in the interior of Africa, near the source of the Nile, Ptolemy placed a mysterious mountain range called the Mountains of the Moon. The fabled Mountains of the Moon actually exist. They are now called the Ruwenzori, located on the border of Uganda and Zaire. They reach almost 17,000 feet and are covered with glaciers even close to the equator. The summits are usually concealed by cloud. On the rare occasions when the summits were visible, the lowland people had no idea what the white covering of the summits was. Some people guessed it might be salt.

How did we discover the Earth is round?

One possibility is that the shadow of the earth cast on the Moon during an eclipse is always round. However, the idea that we are seeing the Earth's shadow cast on the Moon is, if you think about it, a very bold one. I suspect we would already have to have some concept of the Earth as a body in space before we could realize we are seeing the Earth's shadow cast on the Moon.

A frequently-cited hypothesis is that people noticed that the hull of a ship disappeared over the horizon before the sails did. But at the 20 miles or so distance to the horizon, an ancient ship would have been nothing but a speck.

On the other hand, if you're a Minoan sailing from Crete to mainland Greece, or vice versa, there are 8000-foot mountains visible from the sea at both ends of the trip. In winter they are covered with snow. I suspect the crucial observation was made by someone on the deck of a ship watching mountains appear and disappear over the horizon.

Here's another possibility. Tall thunderheads are often seen beyond the horizon with just their tops visible. Some can be 20-30,000 feet high. It's easy to conclude that the horizon is blocking our view of the bottom.

Why is there a horizon at all? A sea horizon looks crisp, sharp, and close by (it is). Why don't we just see forever? All of these ideas may have contributed toward the idea that the Earth is round. The common theme is that the horizon is blocking our view of things beyond it, implying that the surface of the Earth must be curved.

Medieval Concepts of the World

Contrary to innumerable myths, the concept that the Earth is round was never lost during the Middle Ages! This durable and ideologically-driven myth is throughly debunked by Jeffrey Burton Russell in Inventing the Flat Earth (Praeger, 1991). Ptolemy, the ruling authority on astronomy, stated explicitly in the Almagest that the earth is a sphere, so how can people have thought the earth was flat?

The early medieval 6th century mystic Cosmas deserves better than he is treated in the video. He had travelled in India and mixed a lot of eastern concepts in with his Christianity; for his time he was quite an explorer. In an age when most people never go out of sight of their birthplace, he went to India. He was inspired enough by ideas in another culture to try to adapt them to his own; that's a rare open-mindedness in any time and place. Cosmas pictured the Earth as the bottom of a box with the heavens forming a vault above. Cosmas never really represented the mainstream of thinking about the Earth's shape, and like many other ancient concepts of the Earth, his was probably not entirely intended to be a literal depiction of the physical form of the Earth.

In the north of his Earth, Cosmas placed a great mountain. In ancient times this mountain was called Mount Meru. This is another fabled mountain that actually exists. It is an isolated 23,000-foot peak in Tibet now called Mount Kailas. In Buddhist and Hindu belief it is considered the center of the world and is still a major focus of pigrimages. Pilgrims take several days to circle the mountain. The Ganges, Brahmaputra, Indus and Sutlej (a major tributary of the Indus) all have their sources nearby - the four largest rivers of the Indian subcontinent.

What Mount Kailas actually is is as remarkable as its myth. The peak has a beautiful smooth pyramidal form, quite different from the jagged shapes of many Himalayan peaks. From base to summit it consists of conglomerate and sandstone, the remains of debris eroded off the Himalayas as they were being uplifted. At one time within the last few million years, this deposit of debris covered the entire region to above the present summit.

The text version of Shape of the World quotes a number of early religious writers as condemning "science". This can be misleading if you don't know that Latin scientia> means "knowledge", and often referred to philosophical speculation. Some of these speculations were on pretty much the same level as the fabled medieval question of how many angels could fit on a pinhead, or in more modern terms, where Elvis might be hiding. Before the invention of the telescope, speculating on the nature of the stars (as opposed to practical uses like timekeeping and navigation) was pretty unproductive. With only a tiny part of the world mapped, speculating on undiscovered continents is pointless.If many of the more extreme early religious writers were pretty anti-intellectual or frittered away their energies on trivia, so did some of the movements they condemned.

Isidor of Seville (7th century) contributed one of the most popular of medieval map styles and one of the most enduring of geographic fads. The map style was the T-map, with east at the top. The known world was a circle surrounded by water and divided into three continents by a T-shaped waterway. Asia was the top half of the circle. The left crossbar of the T was the River Don and the right the Red Sea. The stem of the T was the Mediterranean with Europe on the left and Africa on the right. Some maps were geographically accurate, others simply schematic. Isidore's fad was the search for the Garden of Eden.

It's important to keep things like this in context. Focusing on the aspects of the Middle Ages that seem to us most absurd is misleading, just as if someone 500 years from now were to conclude that we spent all our time searching for Elvis.

The search for the Garden of Eden is treated humorously in Shape of the World, a speculation fully as idle as any condemned by early Church writers. The account in the book of Genesis pictures Eden as surrounded by four rivers, two of which, the Tigris and Euphrates, are well known and the other two are unidentified. Interestingly enough, there are three places where the Tigris and Euphrates are close together: their delta on the Persian Gulf, near Baghdad, and near their source in Turkey. Most Western searchers have tended to focus on Iraq (ancient Mesopotamia) but the Kurds, understandably, believe it was in their region.

The medieval upsurge in guidebooks for pilgrims, as well as the craze for relics, actually mark an important step in the evolution of Western thought. Europeans began demanding physical evidence for their beliefs. It marks the return of an empirical, Ionian sort of mentality.

Our existing manuscripts of Ptolemy's Geographia are due to the monk Maximus Plenudes who discovered a text of Ptolemy's work in 1295. It had Ptolemy's lists of geographic coordinates but no maps. Plenudes commissioned local artists to produce maps, probably incorporating existing geographic knowledge. Thus the versions we have today are a hybrid of Ptolemy's and medieval information.

Essential Points


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Created 13 January 1998, Last Update 15 January 2020