De Astronomia

Tumbarello 1

Anthony Tumbarello
HIST 321.01
Instructor: Dr. Kiril Petkov
December 8, 2012
De Astronomia
Early Medieval Thoughts on our place in the Universe
The early Middle Ages, a time that is often described as a black shroud covering western civilization, is known scientifically for being stagnant in astronomical thought. However, there were a few lights of education shining through the darkness. Amongst these islands of learned people, there was a very important debate about the structure of the universe and our place in it. This understanding was drawn from a precarious combination of the Greco-Roman astronomical tradition and the Judeo-Christian biblical conceptualization of the universe. The combination in which these two distinct schools of thought were used varied dramatically between scholars. This variation covered the whole spectrum from a strictly pagan Greek astronomy, to a strictly scriptural world view.
One of the earliest intellectuals of the period would be with the encyclopedia writer Martianus Capella, a pagan citizen of Roman Africa. Although not much is known about his life, it is generally accepted that he studied at Carthage during the 5th century CE. Capella is most known for his work De nuptiis, a multiple volume text in which he outlines the seven liberal arts. From reading his volume on astronomy, it is quite evident that he had some access to but not a full understanding of ancient Greek and Roman texts. For example he states that, Eratosthenes, a Greek mathematician from the 3rd century BCE, measured the earth's circumference at 406,010 stadia. This figure contradicts his previous usage of this measurement in his volume on geometry, in which he accurately states Eratosthenes' results to be 252,000 stadia. This has two rather important implications. The first is that this type of discrepancy, which is quite common throughout his work, is likely the result of an incomplete understanding of the subject matter. Figure 1However, the second implication is that in giving the earth a circumference. He is verifying that he understood the Earth to be spherical. His vague understanding of Greek astronomy did yield a rather remarkable viewpoint. As illustrated by Figure 1 and outlined in the following dialogue: "Now Venus and Mercury, although they have their daily risings and settings, do not travel about the earth at all; rather they encircle the sun in wider revolutions. The center of their orbits is set in the sun."3 Even though it is unlikely Valentin Naboth2 1573Capella reached this conclusion on his own, it is still a huge step toward a heliocentric understanding of the universe. Valentin Naboth, the artist of Figure 1, depicts Capella's view of the universe in a way which is comparable to our Copernican understanding of the solar system. However, this is probably not as Capella would have understood it.
Figure 1
Valentin Naboth2 1573
Another student of Carthage in the early 5th century was St. Augustine of Hippo. Any interaction between Augustine and Martianus is not well documented, if it ever happened at all. Despite being contemporaries, Augustine's world view was radically different. He found that the ultimate truth came from scripture. However, Augustine was more prone to listen to traditional Greek thought whenever it remained consistent with the bible.
For Augustine there was no question that the Earth was in the center of the universe. However, he had an interesting opinion on antipodes. This was a theory of the day concerning the existence of an opposite side of the world inhabited literally by those whose feet are opposite ours. His viewpoint on the matter would be somewhat different to that of later Christian scholars. During his discussion on antipodes in The City of God, he seems to hold that the Earth could very well have a spherical shape. However, this is no reason to assume that people live on the other side of the earth. Augustine felt that any land that may exist there would be too distant to reach by boat. This would mean that people that lived there could not have been descended from Adam. According to scripture, there can be no man who is not descended from Adam, and therefore there can be no people on the other side of the earth.
He elaborates on this world view in the following excerpt from The Literal Meaning of Genesis: "At the time when night is with us the sun is illuminating with its presence those parts of the world through which it returns from the place of its setting to that of its rising. Hence it is that for the whole twenty-four hours of the sun's circuit there is always day in one place and night in another."
This stance on the form of the universe is sideways in relation to how people conceptualize the universe today. When asked to visualize the solar system, most people today imagine a bird's eye view of concentric rings representing the orbits of planets around the sun. Augustine saw the universe a bit differently. The sky above was half of a tremendous sphere in which the stationary earth was in the center, meaning the sun, moon, planets, and background stars would rise vertically from the east and fall below to the west. The celestial bodies would continue at their various rates beneath the earth until they re-emerged in the east.
If one were to accuse St. Augustine of any crime against the astronomical sciences, it would be his dissent of astrology. In his confessions, he gives a wonderful story of the child of a slave and the child of a noble born within the same minute. Both children's stars were then read. The stars of the slave child designated him to lead a meager life, while the stars of the noble was said to live a magnificent life. Being born within the same minute, the children's stars should have been identical. This is a lethal blow to astrology, which in it of itself holds no scientific value. However, it has been argued that very pursuit of astrology caused many of the advancements in astronomy throughout antiquity.
About a century later a Byzantine monk, Cosmas Indicopleustes, gave his perspective of the universe. In his work, Christian Topography, he attempts to explain why the earth must be flat. This is clearly stated in the first sentence of his work: "Against those who, while wishing to profess Christianity, think and imagine like the pagans that the heaven is spherical." His stance on this was never a widely accepted belief. However, he represents the antipode to Capella's understanding of the universe. Cosmas offers very little beyond scripture as an explanation to his world view. His arguments largely consist of pointing out the discrepencies in Ptolomy's system of epicycles, which in all fairness he often makes a good point. Such as arguing: "And why have not the moon and the sun their epicycles? Is it that they are not worthy on account of their inferiority?" A short while before that quote he questions why and how these bodies even move at all under Ptolomy's theory. Like Augustine, he condemns astrology and thinks the notion of people living on the other side of the earth to be absurd. However, Cosmas would argue that the sun nor any of the other heavenly bodies ever travels beneath the earth. To him, the earth is the heaviest of all substences, and is in the center bottom of the universe. There is nothing beneath it because nothing but earth could support earth. To say that there is a sky on the other side of the world is to say that the earth is held up by air.
In the mid 7th century Isidore of Seville, an archbishop gave another perspective on the workings of the universe. Like Martianus, he complied an encyclopedia from various Greek sources. Not much, if anything novel was added. However, it is quite evident that he put his own spin on the data. The following two passages from his De rarum natura indicate that he held a diferent view of the world. "The size of the sun is greater than that of the earth and so from the moment when it rises it appears equally to the east and west at the same time." This is a key indicator that Isidore understood the earth to be flat. With a round earth it would be impossible for both the east and the west to see the same sunrise equally.
Despite his belief in a flat earth, he did believe the earth to have hemispheres as outlined here: "A hemisphere is half a sphere. The hemisphere above the earth is that part of the heavens the whole of which is seen by us; the hemisphere under the earth is that which cannot be seen as long as it is under the earth." Regardless of how it may seem at a first glance, he is not refering to the earth as a sphere, but rather the heavens as a sphere that goes around the earth. This shows that Isidor's perspective of the universe was similar to that of Augustine's vertically orientated universe. He does not however, go into a discussion as to whether or not the other side of the world is inhabited.
Figure 2The five Zones of the WorldAs for the layout of the earth itself, Isidore drew from a Greek concept in which the earth was layered into five zones. This to some extent is comprable to the way we label various important lattitudes today. Unfortunately, when Isidore tried to apply this concept to his flat earth it resulted in an earth made up of five individual circular zones circumscribed within a larger circle. This is depicted by Figure 2, which is a rendition of Isidore's original depiction of the five zones. From all of this we can surmise that Isidore viewed the earth like a coin in a soap bubble, a flat round disk surrounded by a sphere on boath sides around which the heavens rotated. The surface of the coin was then divided into smaller circular zones.
Figure 2
The five Zones of the World
As for astrology, Isidore had a rather unique view. Like Augustine and Cosmas, he felt that it was a herasy to attribute any meaning to heavenly bodies based on the pagan dieties with which they were named by. He believed that it was largely an art favored by the devil. However, some good must be found in astrology, since this pratice is what lead the magi to Christ.
Of the four authors one can see a clear spectrum, from completely Greeco-Roman to strictly Judeo-Christian. Martianus Capella's world view was in every way influenced by the pagan astronomical tradition. We see that Isidore of Seville has an honest appreciation for classical astronomy. However, allows certain discrepancies with reality in order to retain scriptual integrity. St. Augustine of Hippo does exibit a comparable willingness to listen to Greek astronomy, but feels data is only second best compared to scripture. This leaves Cosmas Indicopleustes who clearly derives the entirety of his world view from scripture. Perhaps the most intersting thing about this spectrum of opinions is that it's not in chronological order. Rather than gradually changing from one set of beliefs to another, the viewpoint was constantly varying. Astronomy, like other sciences, is not the work of one scientist or author, but instead built on the shoulders of previous scholars. In the early medieval period, this was clearly not the case. Instead, each author came up with their own definition of the universe and our place in it, often disagreeing with their contemporaries and predecessors. This debate would persist until the Renascence.


Works Cited

Brehaut, Earnest Ph.D. An Encyclopedist of the Dark Ages, Isidore of Seville. New York: Columbia University Press, 1912.
Capella, Martianus. "Their Peculiar Behavior Confounds Morals' Minds." Danielson, Dennis Richard. The Book of the Cosmos, Imagining the Universe from Heraclitus to Hawking. Ed. Dennis Richard Danielson. Perseus Publishing, 2000. 78-81.
Cosmas, Indicopleustes, fl. 6th cent. The Christian topography of Cosmas, an Egyptian monk. Ed. John W McCrindle. Trans. John W McCrindle. Vol. I. Surrey: Ashgate, 2010.
Dreyer, J.L.E. A History of Astronomy from Thales to Kepler. Ed. William Harris Stahl. 2nd. Dover Publications, INC., 1953.
Hippo, St. Augustine of. Confessions. Trans. Henry Chadwick. Oxford & New York: Oxford University Press, 1992.
Hippo, St. Augustine of. "De Genesi ad litteram Vol. I." Taylor, John Hammond. Ancient Christian Writers. Trans. John Hammond Taylor. Vol. XLI. New York: Paulist Press, 1982.
Hippo, St. Augustine of. "Whether We are to Believe in the Antipodes." Hippo, St. Augustine of. De Civitate Dei. Ed. Philip Schaff. Trans. Rev. Marcus Dods. Vol. XVI. Grand Rapids: WM. B. Eerdmans Publishing Company, 1886.
Naboth, Valentin. Syftema maximarum vniurfitatis partium ex fententia Martiani Capella.
Stahl, William Harris. Martianus Capella and the Seven Liberal Arts. Vol. I. New York & London: Columbia University Press, 1971. II vols.
Tauber, Gerald E. Man's View of the Universe. New York: Crown Publishers, 1979.






Stahl, William Harris. Martianus Capella and the Seven Liberal Arts. Vol. I. (New York & London: Columbia University, 1971). II vols. 9-12.

Stahl, Martianus Capella and the Seven Liberal Art, 190-191
2 Naboth, Valentin. Syftema maximarum vniurfitatis partium ex fententia Martiani Capella.
3 Capella, Martianus. "Their Peculiar Behavior Confounds Morals' Minds." Danielson, Dennis Richard. The Book of the Cosmos, Imagining the Universe from Heraclitus to Hawking. Ed. Dennis Richard Danielson. (Perseus, 2000), 80.

Hippo, St. Augustine of. "Whether We are to Believe in the Antipodes." Hippo, St. Augustine of. De Civitate Dei. Ed. Philip Schaff. Trans. Rev. Marcus Dods. Vol. XVI. (Grand Rapids: WM. B. Eerdmans, 1886).
Hippo, St. Augustine of. "De Genesi ad litteram Vol. I." Taylor, John Hammond. Ancient Christian Writers. Trans. John Hammond Taylor. Vol. XLI. (New York: Paulist, 1982), 8.
Hippo, St. Augustine of. Confessions. Trans. Henry Chadwick. (Oxford & New York: Oxford University, 1992), 118.
Cosmas, Indicopleustes, fl. 6th cent. The Christian topography of Cosmas, an Egyptian monk. Ed. John W McCrindle. Trans. John W McCrindle. Vol. I. (Surrey: Ashgate, 2010), 1.
Cosmos, The Christian Topography of an Egyptian Monk, 14.
Brehaut, Earnest Ph.D. An Encyclopedist of the Dark Ages, Isidore of Seville. (New York: Columbia University, 1912), 147.
Brehaut, An Encyclopedist of the Dark Ages, Isidore of Seville, 146.
Brehaut, An Encyclopedist of the Dark Ages, Isidore of Seville, 53.
Brehaut, An Encyclopedist of the Dark Ages, Isidore of Seville, 52.
Brehaut, An Encyclopedist of the Dark Ages, Isidore of Seville, 141-142.