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Egypt

The ancient Egyptians conceived the sky as a roof placed over the world supported by columns placed at the four cardinal points. The Earth was a flat rectangle, longer from north to south, whose surface bulges slightly and having (of course) the Nile as its center. On the south there was a river in the sky supported by mountains and on this river the sun god made his daily trip (this river was wide enough to allow the sun to vary its path as it is seen to do). The stars were suspended from the heavens by strong cables, but no apparent explanation was given for their movements.

There is no unique Egyptian creation myth, yet one of the most colorful versions states that at the beginning of the world, Nuit, the goddess of the night, was in a tight embrace with her husband Sibû, the earth god. Then one day, without an obvious reason, the god Shû grabed her and elevated her to the sky (to become the sky) despite the protests and painful squirmings of Sibû. But Shû has no sympathy afor him nd freezes Sibû even as he is thrashing about. And so he remains to this day, his twisted pose generating the irregularities we see on the Earth's surface (see Fig. 2.2). Nuit is supported by her arms and legs which become the columns holding the sky. The newly created world was divided into four regions or houses, each dominated by a god. Since the day of creation Sibû has been clothed in verdure and generations of animals prospered on his back, but his pain persists.


 
Figure 2.2: Nuit the sky above Sibû the Earth after being separated by Shû in a version of the Egyptian creation myth. 
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An extended version of this myth imagines that in the beginning the god Tumu suddenly cried ``Come to me!'' across the cosmic ocean, whence a giant lotus flower appeared which had the god Ra inside, then Ra separates Nuit and Sibû, and the story proceeds as above. It is noteworthy that creation did not come through muscular effort, but through Tumu's voiced command. This later evolved into the belief that the creator made the world with a single word, then with a single sound (yet the creation through pure thought was not considered).

After creation the gods, especially Thot (Fig. 2.3), teach the arts and sciences to the Egyptians. In particular Thot taught the Egyptians how to observe the heavens and the manner in which the planets and the sun move, as well as the names of the (36) constellations (though he apparently neglected to tell them about eclipses which are never referred to).


 
Figure 2.3: The Egyptian god Thot.  
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The study of the heavens was not made for altruistic purposes but with very practical aims: a good calendar was necessary in order to prepare for the regular flooding of the Nile as well as for religious purposes. The Egyptian calendar had a year of precisely 365 days and was used for many centuries; curiously they never corrected for the fact that the year is 365 1/4 days in length (this is why every four years we have a leap year and add a day to February) and so their time reckoning was off one day every four years. After 730 years this deficiency adds up to 6 months so that the calendar announced the arrival of summer at the beginning of winter. After 1460 years the Egyptian calendar came back on track and big celebrations ensued.

Egyptians knew and used the water clock whose origin is lost in the mists of time. the oldest clock in existence dates from the reign of the pharo Thutmose III (about 1450 B.C.) and is now in th Berlin Museum.

Most of Egyptian mathematics was aimed at practical calculations such as measuring the Earth (important as the periodic Nile floods erased property boundary marks) and business mathematics. Their number system was clumsy (addition was not too bad but multiplication is very cumbersome). To overcome this deficiency the Egyptians devised cunning ways to multiply numbers, the method, however, was very tedious: to obtain 41 × 59 = 2419 nine operations had to be performed (all additions and subtractions); yet they were able to calculate areas and estimate the number $ \pi $. Examples of calculations have survived in several papyri (Fig. 2.4).


 
Figure 2.4: An example of Egyptian papyri, the Moscow papyrus and its translation; the text contains the estimate $ \pi $ =256/81=3.1605. 


Unlike the Greeks who thought abstractly about mathematical ideas, the Egyptians were only concerned with practical arithmetic. In fact the Egyptians probably did not think of numbers as abstract quantities but always thought of a specific collection of objects when a number was mentioned.


next up previous contents
Next: Other nations Up: Egypt and Babylon Previous: Babylon

Jose Wudka
9/24/1998