Category Archives: Western Civilization

The future!

Can you see into the future? Thinking in linear time allows us to think about the future. It’s not easy, of course. People do use a timeline to plan projects and life goals, so that they can make them happen. In fact, I’m using a timeline for this project—writing this history which I plan to make into a book. Do you think about what you’ll be doing in 5 years? Successful people plan for the future. Holy cow, I sound like I’m selling life insurance.

The Torah (what Christians call the Old Testament), with its timeline of many generations of Jews, was read by ordinary people and changed the way ordinary people think about time and themselves.

In the Torah, ordinary people became important. Religious stories of other cultures were about gods and goddesses. Mortal beings had supporting roles in those stories, like when the mortal Paris judged a goddess beauty contest, or the gods created Enkidu to hang out with the semi-divine Gilgamesh. You don’t get a sense that the gods and mortals have a destiny together, because the stories don’t talk about a future. On the other hand, the stories in the Torah are about ordinary mortals who share a past and future with one God. When ordinary mortals—everybody, us—see ourselves as part of a destiny, the way we think about ourselves is changed. A person with a future, a destiny, has free-will and the mindset to break free of a cycle. You can see how a person with the inheritance of generations of history—aligned with God’s—has more free-will than the person who lives only in a cycle, the now, the present.

Timelines

Thinking in linear time changes our brains. Do you like history? History lovers keep a timeline in their heads. My dad loves history. He was a handy guy to have around when I had history homework. You can give my dad a date in history and he’ll tell you all about what was going on in the world at the time, what people were likely wearing, what they ate, how they got around, who were the big political players. He taught me how to research, how to use a library. When I was awarded the contract to illustrate A Prairie Dog for the President, I phoned Pop who started giving me facts about Lewis & Clark—just off the top of his head. Don’t watch a historical movie with my dad—if they monkeyed with the research he’ll take it apart!

A timeline is a foundation you can build on. If you have a general idea where the big events are on a timeline, you can add new eras and dates in their proper places. A timeline is a fantastic tool for organizing the way you think.

Happy Father’s day!

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The Torah and linear time

Linear time gives us the ability to recognize a long-reaching past and plan for a long-reaching future. That’s how our brains get changed.

The Hebrew Bible, the Torah, the Old Testament tells the story of the Jews from the beginning of mankind to the time of Babylonian captivity. It’s a long read, but because I’m a sweetheart of a guy, I’ll tell you the entire Torah in one sentence—if you don’t mind standing on one foot:

In the beginning, God creates everything time space the world plants animals and human beings who He tells not to do the wrong things but because the human beings had free will they always do the wrong things Adam & Eve eat the apple of knowledge and the perfect world falls into evil everybody splits up into separate nations and languages God makes a deal with Abraham if you have faith in Me I’ll make you your kids even your great-great-great-great-great-great-great-great-grandkids a great nation Abraham says okay so Abraham son Isaac & grandson Jacob are the fathers of the Israelites everybody moves to Egypt eventually Pharaoh makes them slaves so Moses leads the Israelites out of Egypt God gives them the 10 Commandments they wander around the Middle East for 40 years then settle in Israel the Israelites keep disobeying God they try government by judges like Samson who is really strong because he promised God he wouldn’t cut his hair then kings like Saul who goes a little crazy then David who kills Goliath and writes Psalms but steps out with Bathsheba and wise Solomon who builds the temple but has 700 wives and worships other gods so it doesn’t work out so good and the kingdom splits into Israel & Judah the nations next door come in and conquer first Israel then Judah and cart everybody off to Babylon and Persia the prophets tell us where everything went wrong and what we need to do better from now on.

Okay, you can put your other foot down now. The Torah tells the story of a long parade of generations—“so-and-so begat so-and-so, who begat…” Those stories are told in linear time. Linear time is the natural medium for telling about many generations of people.

We claim who we are by telling our stories. There’s a reason the Torah was written down during the Babylonian Captivity. The Jews, separated from their homeland and their Temple, told us who they are by committing the Torah to paper. Without their own place, the priestly writers emphasized time—and made it sacred.

More about the Major Prophets: , Isaiah, Jeremiah, Ezekiel and Daniel.

Side note: Hebrews, Israelites and Jews refer to the same people. They were Hebrews up until Jacob wrestled with an angel and was renamed Israel (means ‘wrestles with God’) and his people renamed themselves Israelites. At the time of the Babylonian Captivity, Jews is what the Persians called people from Judah (because Israel had been wiped out). Of course there’s some overlap.

The Jews

“Let’s go! I gotta become Abraham!”

Back when we were talking about the Sumerians of Mesopotamia, I mentioned that Ur was the city Abram left so that he could become Abraham. Whatever became of him? Well, he and his wife Sarai (later Sarah) answered the call of the Lord and set up shop in Canaan—more or less the same place as modern Israel.

Click over here and scroll down to see a map—Ur is lower-right just above the globe. They traveled due west to reach Canaan (with a side-trip to Egypt).

Abraham was the forefather of the Hebrews, the Israelites, the Jews. He and they were (and are) monotheistic—they worshiped one God (mono = one, theo/deo = god). As we’ve seen, the Sumerians, Egyptians and Greeks had religions with more than one god—they were polytheistic. Worshiping only one God was a big deal. It made the Hebrews different from everybody else. Abraham’s story begins in the very last verse of Genesis Chapter 11 if you have a Bible handy.

Side note: adding the ‘h’ to Sarai’s and Abram’s names signifies ‘of many.’ ‘Abram’ meant ‘father,’ ‘Abraham’ means ‘father of many.’ ‘Sarai’ meant ‘princess,’ ‘Sarah’ means ‘princess of many.’ God was keeping up His end of the deal by making Abraham the father of the Hebrews (Genesis 17:5).

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Galileo & Pheidippides

I’m thinking about using this image to promote The Western Civ User’s Guide to Time & Space.

It’s Galileo, who invented the pendulum clock, and the Greek hero Pheidippides, who ran 26 miles from Marathon to Athens with news of victory over the Persians.

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How he did it

Just to recap from the last couple of posts: First, Eratosthenes guessed the Earth was round like a ball. Second, he knew that at noon on the Summer solstice, the Sun shone directly overhead in the town of Syene, which was 5,000 stadia south of Eratosthenes.

Third, Eratosthenes guessed the Sun was really big—huge, even. He noticed that shadows cast by the Sun are all parallel, so all the Sun’s rays must be parallel, too. Parallel means 2 or more lines that never touch—they stay the same distance from each other. Think train tracks.

SO, Eratosthenes—in Alexandria, 5,000 stadia north of Syene—put a stick (like the gnomon of a sundial) in the ground and made sure it was plumb. That stick was pointing down to the center of the Earth. If Earth is round, the well in Syene and Eratosthenes’ stick won’t be parallel, right? They’ll be at an angle to each other. Eratosthenes didn’t know exactly how many degrees that angle was, but in Alexandria at noon on June 21st, his stick cast a shadow.

There weren’t any shadows in Syene, because the Sun was directly overhead. He measured the stick, he measured the shadow, and used those measurements to draw an angle. The angle turned out to be a little over 7 degrees, or 1/50 of a circle.

Eratosthenes knew the distance from Alexandria to Syene was 5,000 stadia. He multiplied 5,000 by 50 to get the circumference of the Earth—250,000 stadia. In modern measurements that works out to be 28,738.418 miles or 46,250 kilometers.

The actual polar circumference of Earth is about 24,860 miles or just a bit over 40 thousand kilometers. The stadion Eratosthenes used may have been a little different from the standard unit. But even today, right now, if you search the internet for the circumference of the Earth, you won’t get just one answer.

Eratosthenes was a genius who used what he knew and observed, along with what he guessed at, to calculate something that no one knew—and he did it pretty accurately.

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Plumb

A plumb line or plumb bob.

Last post I rattled on about how the well at Syene was plumb.

‘Plumb’ means straight up-and-down. Builders used to use a plumb line—a string with a weight tied onto it—to check that their walls were straight up-and-down. A plumb line will always point to the center of the Earth. Nowadays they use a spirit level. Builders who dug wells made sure that the hole they dug was plumb—pointing directly toward the Earth’s center.

Why was it so important to Eratosthenes that the well at Syene (a town located on the Tropic of Cancer) was pointing directly at the Earth’s center at noon on June 21st—the Summer solstice?

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The well at Syene

So how did Eratosthenes figure out how big around the Earth is? Here’s how:

First, he assumed the Earth is round like a ball.

Well at Syene.

Second, he knew several things about a little town called Syene. It is 5,000 stadia (575 miles or 925 kilometers) directly south of Alexandria. There was a well in the center of town, dug deep and plumb—straight toward the Earth’s center. At noon on June 21st, the Summer solstice, you could see the Sun reflected on the water way down in that well, which means the Sun is directly overhead.

Bird’s-eye view of the Sun’s reflection in the well at Syene.

That’s because Syene is located on the Tropic of Cancer. If you happen to be standing on the Tropic of Cancer and it’s noon where you are on June 21 you can draw a straight line from the center of the Earth, through the Tropic of Cancer, to the Sun.

A stadion is an ancient Greek unit of measurement—it’s 600 feet (an eighth of a mile). Stadion is singular (nominative, singular, second declension); stadia is plural (nominative, plural, second declension). 5,000 stadia = 575 miles or 925 kilometers. I hope I declenched in all the right spots. Many thanks to my Greek-scholar pals Jackie J., Michele J. & Joann W!

Eratosthenes


Head-Librarian Eratosthenes explains to a student how to laminate a dust jacket.

In an earlier post, I hinted about how over 2,000 years ago somebody calculated the circumference (how big around) of the Earth. This guy did it using only a well, a protractor and a stick (okay, maybe instead of a stick he used a column, but you could use a stick and get the same result).

I’m talking about Eratosthenes, the head librarian at the Great Library of Alexandria. Alexandria is an ancient city in Egypt, located where the Nile River flows into the Mediterranean Sea. Many scholars lived in Alexandria—like Ctesibius, who perfected the water-clock.

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Summer solstice

Okay, here comes some sciency stuff.

Summer solstice happens twice a year—once in the Northern Hemisphere (June 21) and once in the Southern Hemisphere (December 22). Those are the two days when the Sun spends the most time in the sky.

If you have a globe handy, you’ll see that there’s a line that goes all the way around the middle of the Earth. That’s the equator. It separates the Earth into a northern half and a southern half. Each half is called a hemisphere—’hemi’ means ‘half’ and ‘sphere’ is another word for ‘globe’.

The Sun appears to travel across the sky, but ackshually the Earth is traveling around the Sun and spinning on her axis at the same time. An axis is the line that goes through the center of the Earth from the North Pole to the South Pole. Did you notice that your globe’s axis is tilted? It’s tilted at a little over 27 degrees, because Earth is tilted at a little over 27° in relation to its orbit around the Sun. Because of this tilt, half the year (the time it takes to orbit the Sun) the Northern Hemisphere receives more of the Sun’s rays. The other half of the year, the Southern Hemisphere receives more of the Sun’s rays. The equator gets the Sun’s rays all year round, so it’s always hot there.

It takes one year for Earth to orbit the Sun. When the Northern Hemisphere is tilted toward the Sun it’s Summer there. When the Southern Hemisphere is tilted toward the Sun it’s Summer there.

Getting back to that equator—let’s look at the globe again. There are 2 other lines that also run around the Earth. In the Northern Hemisphere, there’s the Tropic of Cancer. In the Southern Hemisphere, there’s the Tropic of Capricorn. On June 21, the Northern Hemisphere tilts toward the Sun and the Tropic of Cancer gets the Sun’s rays directly. You could draw a line from the Earth’s center through the Tropic of Cancer to the Sun. On December 22, the Southern Hemisphere tilts toward the Sun and the Tropic of Capricorn gets the Sun’s rays directly. You could draw a line from the Earth’s center through the Tropic of Capricorn to the Sun.

On June 21, the Northern Hemisphere has the most daylight of any day of the year. Six months later, on December 22, the Southern Hemisphere has the most daylight of any day of the year.

Remember, when the Northern Hemisphere has the most hours of daylight (Summer solstice) the Southern Hemisphere has the fewest hours of daylight (Winter solstice). The opposite is true at solstice six months later.

Three months after solstice is the day when the day is split equally in two, with 12 hours of daylight and 12 hours of nighttime. This is the equinox. The autumnal (Fall) equinox is September 22 in the Northern Hemisphere. March 21 is the vernal (Spring) equinox.

Why am I telling you this? Well, over two thousand years ago a Greek librarian figured out exactly how big around the Earth is using only a well and a stick—and he did it at noon during the Summer solstice.

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