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CHAPTER ONE
FUNDAMENTAL PHYSICS:
Human Ideas On Cosmic Design
Written history begins in the river valleys of the Indus, Tigris, Euphrates, and
Nile rivers about 7000 years ago. These civilizations developed almost at the
same time, and their trade, conquests, and other interactions are demonstrated
in many common artifacts and cultural traces. The Sumerians along the Tigris
and Euphrates rivers wrote on clay using cuneiform characters, counted in tens,
and observed eclipses, but they developed beliefs in actions generated by the
whims of gods rather than trying to understand the causes of those actions.
The Babylonians developed technologies such as throwing pottery on a wheel and
blending metals to form alloys, and built their famous hanging gardens. The
Babylonians used 60 as a counting unit, so they divided the circle into six
parts, and each part into 60 smaller parts. They divided the day into six parts,
each part into 60 smaller parts, and again divided these into 60 yet smaller parts.
The Egyptians designated 12 hours each for daytime and nighttime. Our present time
system of days, hours, minutes, and seconds is a blend of these two systems.
Artisans along the Indus, as elsewhere, started working in stone, then developed
copper and bronze for art, tools, and weapons. The Babylonian priesthood recorded
their observations of the skies over long periods with such precision that they
eventually were able to define the 6585 1/3 days period for repetition of the eclipse
cycle for the Sun and Moon.
An Egyptian papyrus surviving from about 4000 years ago presents rules for finding
areas of figures and volumes of cylinders and spheres, but it offers no hint how
these rules evolved. Such rules were used each year to redistribute the flood plane
of the Nile into farm areas after the floods subsided, and to collect the taxes when
the crops were harvested. Although the Egyptians left us many examples of their
skills and their highly developed technologies in the pyramids and other fabulous
structures, like the Sumerians they relied on superstitions and faith to explain
the world.
Greeks appear in history as long-haired invaders from the north (the Achaean Greeks)
who came down into the Mediterranean regions in 1600 B.C. employing bronze weapons.
Homer described the heroes of this people and their gods of Olympus in his Iliad and
Odyssey, where the gods showed rather human motivations and frequently interfered with
human adventures. The invasion by the Dorian Greeks occurred 500 years later
using iron weapons, displacing the Achaeans out to more remote regions of the
Mediterranean. The Achaeans founded the twelve cities of Ionia along the Asian
side of the Aegean Sea, where they demonstrated the energy often observed in frontier
towns in subsequent migrations. It is amongst these Ionian Greeks that the beginnings
of scientific thought and methods are found.
Thales
Thales was born in Miletus, the most southern of the twelve cities of Ionia, about
620 B.C. Miletus was a community of mostly freeborn craftsmen who imported raw
materials and exported arts and crafts all over the civilized world. It was
natural for Thales to travel to other cities; he studied in Babylonia and Egypt.
While in Egypt he measured the height of the pyramids by measuring the length of
the shadow at the time of day when his own shadow equaled his height. On returning
to Miletus, Thales founded Greek geometry when he established proofs of many
elementary geometric propositions. This invention of the proof of theorems was
the beginning of mathematical science. As well, from this beginning geometry
became the favored mathematical study of the Greek intellectuals and remained
so for the next two millennia.
When Thales formed his notion of the structure of the world, based largely on
Babylonian concepts, he left out the roles of gods, proposing that observable
matter does what is natural to it. This is the first example of strict cause
and effect in explaining the observed phenomena of the world and may be the
greatest of Thales' contributions to science. He used his knowledge of Babylonian
astronomical observations to predict a solar eclipse in 585 B.C., gaining fame
throughout Ionia.
So we see that over a few thousand years civilization developed means to improve
their material wealth, their arts, and their weapons of war. They developed
methods to measure land areas and to levy taxes. They developed languages and
writing to record events. They observed the heavens, and attempted to use those
observations to guide them in their agriculture and in other ventures. Finally,
we see that the wish to better understand the world around them led the early
Greeks to establish a mathematical science, and led them to the notion that they
might understand and explain what is observed around them. We shall follow the
development of the concepts of science in upcoming pages of this site.
Check back soon for the Complete Story!
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