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Natural Science - Year I

Unit 4: Early Babylon and Egypt: Astronomy

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History Lecture for Unit 4: Science in the Civilizations of the Ancient World I

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Outline/Summary

Science in Egypt and Mesopotamia

According to our best archaeological studies, the earliest cultures with large cities arose around five to six thousand years ago in India, China, the river valleys of Mesopotamia, and along the Nile River in Egypt. Since the science we are studying is largely the product of Western and European cultures, we will start our historical survey with the civilizations of Mesopotamia—Sumer, Babylon, and Assyria—and the kingdoms of Egypt, and the tiny but ultimately very influential kingdom of Israel.

Outside the cities of the great river valleys, farmers cultivated the fields and raised the food, both plants and animals, necessary to support both themselves and the city dwellers. Merchants carried goods from city to city, and sometimes sailed to nearby coasts, to trade for those things not locally available. Within the fortifications built to withstand invasion, the citizens wove cloth, smelted metals into tools, bought and sold their wares, wrote records for business and pleasure, made laws, and worshipped the deities whom they believed ordered the universe and controlled their own lives. Their stories of creation tell us something about how each culture believed the natural world around them was created, and whether it was ordered, and if so, who was in control of it. Their conclusions had enormous impact on how we view nature today, and why our scientific methods rest on the idea that we can predict the behavior of natural phenomena.

In this unit, we look at four creation stories to see how each explained natural phenomena, especially the weather and the movements of the sun, moon, and stars. These movements were especially important to agrarian societies that needed to know when to plant and when to harvest their crops. Understanding that the moon came back every thirty or so cycles of the sun allowed Babylon and the Israelites to create lunar-cycle based calendars for keeping track of time. Knowing that the sun traced the same path in the sky every 365 days or so led the Egyptians to create a solar-based annual calendar.

Mesopotamia

The valleys of the Tigris and Euphrates rivers are surrounded by low mountainous regions, which in ancient times where inhabited by tribes that periodically swept down and invaded the richer civilizations on the plains below. As a result, the history of Mesopotamia is one of a succession of cultures that repeatedly destroyed and rebuilt the cities on the two rivers.

 Period Civilization
3000 - 2300 Sumerian
2300 - 1800 Akkadian
1800 - 1600 Old Babylon
1600 - 1200 Hittites
1200 - 900 No dominant empire
900 - 650 Assyrian domination
630 - 600 New Babylon
550 - 330 Persian
330 - 100 Alexander, Hellenistic Culture

The peoples of Mesopotamia had to contend not only with unpredictable invasions and new rulers, but with unpredictable flooding from their rivers, or flash-floods from storms in the low nearby hills. It should not be surprisingly that their fear of flooding even while they depended on the rivers for agriculture found its way into the Enuma Elish, the Babylonian creation myth. In this story, Apsu of the sweet water and Tiamat of the bitter water mingle their waters together, and create the gods, land, and the heavens. There is immediate discord between the gods, and Apsu is destroyed. In revenge, Tiamat releases many monsters, which destroy every living thing they encounter and create chaos throughout the universe. To survive, the gods chose their strongest member, Marduk, to confront Tiamat, and in the form of a great storm he overcomes Tiamat and her allies. Marduk then creates the earth and heavens from the remnants of Tiamat's body. The Enuma Elish explains how Marduk sets the universe in order:

Marduk Creation Story Tablet

He projected positions for the Great Gods conspicuous in the sky, he gave them a starry aspect as constellations; he measured the year, gave it a beginning and an end, and to each month of the twelve three rising stars. When he had marked the limits of the year, he gave them Nebiru, the pole of the universe, to hold their course, that never erring they should not stray through the sky.

For the seasons of Ea and Enlil he drew the parallel. Through her ribs he opened gates in the east and west, and gave them strong bolts on the right and left; and high in the belly of Tiamat he set the zenith. He gave the moon the luster of a jewel, he gave him all the night, to mark off days, to watch by night each month the circle of a waxing waning light. 'New Moon, when you rise on the world, six days your horns are crescent, until half-circle on the seventh, waxing still phase follows phase, you will divide the month from full to full.

'Then wane, a gibbous light that fails, until low down on the horizon sun oversails you, drawing close his shadow lies across you, then dark of the moon- at thirty days the cycle's second starts again and follows through for ever and for ever.

The Enuma Elish concludes with a catalog of the gods Marduk controls. Many of them are destroyers or gods of storm, reflecting the Babylonian view of a universe in which the gods could visit sudden destruction on humankind, but were themselves subject to outside forces, particularly to each other. The earth and stars are not particularly good or bad, but subject to the acts of the gods. Although Marduk has set some kind of order on their movements, the sun and stars could change course at any whim of a god.

The Mesopotamian cultures turned to any method that promised some way to predict the future, and developed complex methods of astrology, since the motions of celestial objects were more reliable than the more immediate phenomena of their weather, or the floods of the rivers. Without the aid of telescopes, they were dependent on naked-eye observations of the sun, moon, planets, and stars, which they recorded and retained through invasions and changes of dynasty. The library of King Ashurbanipal (668-626 bce) at Ninevah contained many tablets with dated observations of the position of planets or the moon in a given constellation.

From these observations, it is clear that the Babylonians discovered that the planetary motions, though complicated, really were periodic—that is, they followed a pattern which repeated itself over and over again with only small variations. This helped them accurately predict eclipses and planetary conjunctions several years ahead of time. Later, their records (along with those of the Assyrians who conquered Babylon) passed to the Greeks, who used them to build models of the motions of the planets, sun, and moon.

Egypt

In contrast to Mesopotamia, the Nile River valley was surrounded by a nearly uncrossable desert that kept out invaders, and preserved the ruling dynasties over many centuries. Unlike the Tigris and Euphrates, which could flood at odd times of the year, the Nile rose reliably at the same time each year. The predictability of the Nile's behavior permeates Egyptian cosmology, and gives it more a sense of the serenity, than the world view of the Mesopotamians. There was always the possibility that crops could fail due to drought or blight, but unpredictably sudden floods were unlikely.

For nearly three millennia, Egyptian rulers held the central river area and the delta of the Nile as a single political entity until Alexander the Great invaded and conquered the weak rulers of the late dynastic period in 332 bce There is considerable debate about exactly when the "periods" of Egyptian history begin and end; and some historians include the early dynastic period in the chart below in the Old Kingdom. The astute reader will note that there are some missing dates: these are interregnum periods when there was no clear single ruler for the entire valley.

 Period Civilization
Before 3000 - 2575 Early Dynastic Period
2575 - 2150 Old Kingdom
2040-1640 Middle Kingdom
1540-1070 New Kingdom
1070-332 Late Dynastic Period
332 bce - 396 ce Hellenist/Roman Domination

By 3100 bce , the Nile River valley had been united under a single ruler. From about 2800 to 2600, pharaohs of the early dynastic period constructed the pyramids, most of which were built at Giza and Memphis, near the Nile delta, and the great temples of Karnok and Luxor, south on the Nile at Thebes. These monuments show a level of technology much greater than that in surrounding cultures. The Egyptians had to be able to plan their monuments, find and transport the materials, and make the tools to build them. They also had to organize thousands of workers into a cooperative labor force. The Egyptians developed a form of picture writing using hieroglyphs to keep track of all the information necessary to build pyramids, run cities, irrigate fields, and incidentally, do calculations to determine the size of fields and record their observations of solar, lunar, and planetary motions. Because they wrote on cave and tomb walls and on papyrus (a plant leaf which, when properly prepared and kept dry, doesn't disintegrate), we have many of their manuscripts. From these, we have learned something about their medicine, their mathematics and their astronomy.

Egyptian sources record several different versions of creation mythology. In the Helipolitan Creation myth from the Pyramid Texts, the gods and all of the universe was created from nothing. As with the Mesopotamian stories, the Ennead or chief gods (seven, eight or nine of them, depending on the version) were created first. There is no war among the gods. Instead, each takes under his or her domain some part of nature, creating and maintaining the mountains, sea, sky, and the sun, moon, and stars. Later myths tell the story of Osiris, son of the earth god Geb, who is slain by his brother and later resurrected to become the judge and ruler of those who have passed from earthly life. Osiris quickly became associated with the "dying away" of the waters of the Nile and their return, and his kingdom was one of peace and rest.

The Egyptians also believed that their king or Pharaoh became a god on his death, entering into the panoply of the heavens with splendor and power. In the Pyramid Texts, which were discovered in 1882 in the pyramid of Teti, there is a long description of what happens when the King dies.

The sky is overcast, The stars are darkened,
The celestial expanses quiver,
The bones of the earth-gods tremble,
The planets are stilled,
For they have seen the King appearing in power
As a god who lives on his fathers
And feeds on his mothers;
The King is a master of wisdom
Whose mother knows not his name.
The glory of the King is in the sky,
His power is in the horizon
Like his father Atum who begot him.
He begot the King,
And the King is mightier than he.

Early in the Old Kingdom, Egyptian priests were responsible for making sure that the religious observations were done on the correct day. They had amassed a number of observations about the stars, the sun, the moon, and the visible planets (Mercury, Venus, Mars, Jupiter, and Saturn). They made the straightforward observation that the sun and stars move daily from east to west across the sky. They also realized that the sun moved eastward a little bit each day against the background of the stars. Stars which came out "just after sunset" would be lost a few weeks later in the sun's glare, only to show up a month or two later (depending on how bright the star was) as a morning star, shining westward of the sun a little before dawn. In one case, that of the star Sirius, this heliacal rising (rising with the sun) meant the Nile was about to flood.

The Egyptians also tracked the lunar cycle, and noticed that the time between new moons wasn't exactly thirty days. This caused a problem: they could either track time by the sun or by the moon, but not both. Eventually, they chose a solar year (365 days) made of twelve 30-day months and 5 special days. It was easier to use this "civil" calendar for dating business and government events, even if they had to throw in an extra day once in while to kept it lined up with the seasons.

Having linked one heavenly event (Sirius rising) successfully with an earthly one (the Nile rising), the priests were more than eager to find other relationships between regular celestial events and earthly ones. This attitude gave rise to the practice of astrology, where predicting future events became more detailed, down to predicting events in the lives of individuals. Celestial events such as eclipses (where either the sun or moon is in front of the other) and conjunctions (where two or more planets seem to come together in the sky) became important portents of events to come. Each major celestial object—sun, moon, and planet—was identified with an Egyptian deity, and its movement and appearance told the life story of that god or goddess.

China

Like Mesopotamia and Egypt, the great civilizations of China developed along rivers: the Yellow River in the north, and the Yangze River in the middle of what is now China. Both rivers flooded catastrophically and unpredictably from time to time, but with somewhat less frequency than those of the Mesopotamian plain.

In an interesting contrast to the dominant polytheistic creation stories of Mesopotamia and Egypt and the monotheistic creation story told in Genesis that became central to the Judeo-Christian tradition, the earliest Chinese creation stories we have do not talk about gods — and there are several competing versions. The Daodejing or Tao Te Ching, somtimes simply called the Laozi is one of the Classic Chinese texts, written by the 4th centure bce . Its short account of creation begins:

There was something featureless yet complete, born before heaven and earth; Silent – amorphous – it stood alone and unchanging. We may regard it as the mother of heaven and earth. Not knowing its name, I style it the "Way."

The Way gave birth to unity, Unity gave birth to duality, Duality gave birth to trinity, Trinity gave birth to the myriad creatures. The myriad creatures bear yin on their back and embrace yang in their bosoms. They neutralize these vapors and thereby achieve harmony.

A much later version of the story also emphasizes the duality of the universe, and presents nature as a balance of opposing forces, yin and yang:

Before the Great Plainness (or Great Basis, Taisu 太素) came to be, there was dark limpidity and mysterious quiescence, dim and dark. No image of it can be formed. Its midst was void; its exterior was non-existence. Things remained thus for long ages; this is called obscurity (mingxing 溟涬). It was the root of the Dao. … When the stem of the Dao had been grown, creatures came into being and shapes were formed. At this stage, the original qi split and divided, hard and soft first divided, pure and turbid took up different positions. Heaven formed on the outside, and Earth became fixed within. Heaven took it body from the Yang, so it was round and in motion; Earth took its body from the Yin, so it was flat and quiescent. Through motion there was action and giving forth; through quiescence there was conjoining and transformation. Through binding together there was fertilization, and in time all the kinds of things were brought to growth. This is called the Great Origin (Taiyuan 太元). It was the fruition of the Dao.

Some modern historians see in these more abstract explanations the beginning of scientific thought, at about the same time that the Greeks and Hellenists were proposing universal principles of matter. The Dao or "way" is the great cause of all things, and in some ways resembles the "Prime mover" that becomes part of Aristotle's explanation of motion. Later creation stories from China involve deities very much like those in the Mesopotamian stories, whose bodies because the physical Earth and Sky.

The Hebrews

The origin of the tribe of Israel as a people is told through the five books attributed to Moses. While this group of people was small, and in its own time, politically much less significant than the surrounding empires of Egypt, Babylon, Assyria, and Persia, the stories of the Old Testament were translated and passed through Greek and Roman hands into Western Europe as background to the story of Christ. As a result, the Creation story in Genesis, and references to God's control of the sun and stars, took western European view of nature and science in a new direction.

 Period Civilization
3000 - 2300 Traditional date of Flood
2300 - 1800 Traditional date of Abraham's arrival in Canaan
ca. 1250 Exodus of Hebrews from Egypt
ca. 1200-1025 Conquest of Canaan
Period of Judges
1025-928 United Monarchy in Israel (Saul to Solomon)
928-586
928-722South Kingdom
928-586North Kingdom
538-312 Restoration under the prophets
312-67 Selucid Domination
(Macabbean revolt 167-164)
67 bce - 138 ce Roman Empire

The Creation story recorded in the first chapter of Genesis is very different from the chaos and violence pictured by the Mesopotamians, or the more serene view of the universe favored by the Egyptians. The God depicted in Genesis exists alone in glory outside of the nothingness of the universe. There is no pantheon of other gods. His creative activity proceeds in a carefully-structured sequence that creates a world able to support life and, in particular, mankind. The sun, moon, and stars are part of that order.

And God said, "Let there be lights in the firmament of the heavens to separate the day from the night; and let them be for signs and for seasons and for days and for years, and let them be lights in the firmament of the heavens to give light upon the earth." And it was so. And God made the two great lights, the greater light to rule the day, and the lesser light to rule the night; he made the stars also. And God set them in the firmament of the heavens to give light upon the earth, to rule over the day and over the night, and to separate the light form the darkness. And God saw that it was good."

Genesis clearly sets the religion of the Hebrews apart from that of their Fertile Crescent neighbors. Celestial bodies like the sun and moon are not gods, but mere creations of the One God, subject to God's plan and purpose. The world God has created is good in every respect, the proper place for human beings to live, and to have families and raise them in a world of abundance. When sin enters, it diminishes the goodness of God's creation, but does not destroy it. Nor will God wipe out all good with the evil of fallen men; rather, He purges the world with a great flood, but spares Noah and his family, and enough animals to start again. The events of the Flood bring about a new relationship between God and his creation. In his promise to Noah, God binds and limits Himself:

Then Noah built an altar to the Lord and, taking some of all the clean animals and clean birds, he sacrificed burnt offerings on it. The Lord smelled the pleasing aroma and said in his heart, "I will never again curse the ground because of man, even though every inclination of his heart is evil from childhood. And never again will I destroy all living creatures, as I have done. As long as the earth endures, seedtime and harvest, cold and heat, summer and winter, day and night, will never cease."

We inherit from the Jewish tradition the understanding that the world was created by a transcendent God, that it was good, and that it follows an immutable physical law. These concepts have profound implications for how we now look at the universe and try to explain the events that we see. If the universe is good, if God has pronounced His pleasure with each aspect of the physical world from the stars of the sky to the smallest plants, then that physical reality is worthy of our careful study and the effort of our honest stewardship, even in its broken and fallen state. The patterns that we see in natural phenomena are not circumstantial, but the design of a God who can order and maintain them, and who even invites us to study and wonder at them. And if an all-powerful God has created the world for us, then we are truly loved:

When I look at thy heavens, the work of thy fingers,
the moon and the stars which thou hast established;
what is man that thou art mindful of him,
and the son of man that thou doest care for him?

Yet thou hast made him little less than God
and dost crown him with glory and honor.
Thou hast given him dominion over all the works of thy hands.....

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