WEBVTT

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Can you hear me?

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Yes,

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I think you can hear me now,

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but you don't see me.

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That's because you have ears.

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If you close your eyes and reach for the screen

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you will know it's there.

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You feel it through your skin.

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If you have not been allowed to touch it,

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at least you can smell it,

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and after the hot plastic smell

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you will realize that your monitor has to be there.

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Luckily, you have a nose.

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But, what if you taste it?

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Well, it would be more difficult,

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but eventually you'll taste the plastic,

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because you have a tongue.

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You understand the world around you,

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I mean, everything that is around you,

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through those five senses.

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If you have ears,

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you can hear.

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If you have eyes,

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you can see.

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Through your skin,

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you can feel.

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The tongue will help you taste,

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and if you have a nose, you can smell.

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Eyes, ears, nose, tongue and skin are the "tools"

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with which you were born.

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Tools that help you understand 
the world around you.

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But, how did you know all this?

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Just because you noticed?

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And how did we divide them into five senses?

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The answer is science.

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Because the world is so complicated

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we use science to discover and define.

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But, what is science?

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"Investigation and study of nature

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by observation and reasoning."

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or "the sum of all knowledge

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obtained through research."

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Basically a sum of tests, numbers and letters,

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which, all together can define.

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But how?

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Most people recognize marks as values,

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and the best known groups are 
letters and numbers.

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They are inventions which help us

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to understand our environment.

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To better understand how these marks

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came into existence

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let's see a brief history of mathematics.

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Human beings, from our earliest beginnings,

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have searched for solutions to basic problems.

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Building homes, measuring space,

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keeping track of seasons and counting objects.

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Over thirty thousand years ago

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early paleolithic people

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kept track of the passing seasons

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and the changes of weather for planting.

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To represent the passing of time

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they carved tally marks on cave walls

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or slashed tallies on bones, wood or stone.

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Each tally stood for one.

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But this system was awkward

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when it came to large amounts.

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So symbols were eventually created

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that stood for groups of objects.

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Sumerian clay stones have been found

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that date to the fourth millennium BC.

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A small clay column was used for one,

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a clay ball was used for ten,

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and a large cone stood for sixty.

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Written records from around 3300 BC show

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that Babylonians inscribed amounts

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on clay tablets with a reed.

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They used a nail shape for ones,

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and a V on its side for tens,

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combining these symbols to write other numbers.

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For example,

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Babylonians wrote the number 19 as...

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The ancient Egyptians used objects

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from their everyday life as symbols.

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A rod stood for one, a cattle hobble was ten,

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a coiled rope was a hundred,

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a lotus flower was a thousand and so on.

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The number 19 was a cattle hobble and nine rods.

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The early Romans created a number system

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that we still see today.

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Along with other symbols

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they used an X for ten and an I for one.

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By the middle ages

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Romans were putting the I to the right of the X

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for eleven and to the left for nine.

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So they wrote 19 as XIX.

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All these creative number systems

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show groups of objects, as well as individual objects.

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Some of the oldest human counting systems

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rely on fingers and toes.

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So they were based on ones, fivers, tens and twenties.

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The Zulu word for six means

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to take the thumb of the right hand.

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Meaning that all the fingers on the left hand

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had been added up and the other thumb was needed.

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Other systems evolved from commerce.

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The Yoruba, in Nigeria,

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used cowry shells as currency

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and developed an amazingly complex number system.

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It was based on 20s

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and on the operations of multiplication,

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subtraction and addition.

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For example:

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they thought of 45 as (3 x 20) - 10 - 5.

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Knots tied in cords and strings were used

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for recording amounts by many cultures,

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like the Persians.

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The Incas used a more refined version

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called the "quipu":

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A thick cord held horizontally

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from which hung knotted string.

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The kind of knot the Incas used

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along with the length and color of the cord

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represented 1s, 10s, and 100s.

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In today's world almost every industrial culture

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uses the numeral 0 through 9.

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But these symbols weren't invented

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until the third century BC in India

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and it took another 800 years

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for the idea of 0 with place value to be constructed.

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This big idea

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dramatically changed the face of mathematics.

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We humans have always shared with one another.

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When early cultures shared their food and water

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or wanted to divide their land

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in ways that were fair and equal,

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fractions gradually emerged

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as symbols for these fair share situations.

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The ancient Egyptians used unit fractions.

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Fractions where the numerator is 1,

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like 1/2, 1/3 and 1/5,

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and would add and halve these fractions.

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If they wanted to divide three loaves of bread equally

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among five family members,

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they'd first divide the first and second loaves

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into thirds.

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Then, they'd divide the third loaf into fifths.

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Finally, they'd take the remaining one third

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from the second loaf and divide that into five pieces.

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They wrote this as 1/3, 1/5, 1/15.

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Today we would represent this sharing

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with the fraction 3/5.

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3/5 of a loaf for each person,

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or 3 loaves divided by 5 people.

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The Sumerians and early Babylonians

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invented a number system of fractions

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based on 60, that we still use 4000 years later.

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Our days have 60 minute hours

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and 60 second minutes,

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and our circles encompass 360 degrees.

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Chinese societies used an abacus

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with a system based on 10s, although it had no 0.

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An early form of decimal fractions

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came from the abacus.

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For example:

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3/5 would be 6 out of 10 on an abacus

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The Chinese lovingly named the numerator "the son"

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and the denominator "the mother".

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It wasn't until the 12th century

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that common fractions,

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with the bar notation that we use today,

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were invented.

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Even then, these fractions weren't widely used

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until the renaissance period, only 500 years ago.

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Throughout history every culture around the globe

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has created inventive ways to calculate.

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To solve a problem, say... 12 x 15,

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early Russian peasants

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used a system of doubling and halving.

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When an odd number halved resulted in a fraction,

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they rounded down,

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then they added the factors

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associated with the odd multipliers.

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Ancient Egyptians relied on a doubling procedure

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until they produced enough groups.

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Then they added these groups to find the answer.

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Across Europe and Asia, during the middle ages,

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the abacus was the handheld calculator of its day.

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But only very few people knew how to use it,

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usually wealthy merchants and money lenders.

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By simply moving beads that each had place value

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an abacus was a highly efficient way to compute.

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Then, the great Arab mathematician al-KhwÄrizmÄŤ

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introduced the Hindu Arabic numerals 0 through 9,

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into North America and Europe

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and created new procedures for computation.

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These algorithms could be written onto paper.

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Over the centuries learning the algorithms

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became the whole mark of an education

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as students were taught to compute

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long columns of figures,

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borrow and carry,

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and do long division efficiently and reliably.

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They could now keep records of these procedures

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and check results.

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Today complex calculations

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are done with a handheld calculator.

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This means students need the ability

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to check the reasonableness of the answer

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and to have a rich repertoire

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of mental math strategies to do that.

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Most simpler computations like 12 x 15

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can be solved mentally using a variety of strategies.

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As we journey through the rich

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and vibrant history of mathematics

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we can see how ideas and creations

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grew out of our very human need

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to solve the problems in our everyday lives.

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Through time, the mathematical explorations

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of men and women from around the globe,

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have given us fascinating lenses

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that help us to mathematically view

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and make sense of our world.

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Science is the collection of facts

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arrived at by defining what we observe

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and running tests to discover.

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Mathematics, chemistry, and physics represent fixed

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languages which are not subject to interpretation.

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Languages used to describe what we observe and

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to test those observations in order to prove them.

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Think of DNA,

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cells, galaxies,

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fruits,

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laptops,

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air conditioning.

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Think about cars,

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food,

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houses,

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fauna,

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flora.

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Think about atoms,

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body parts,

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climate,

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or the clothes you wear.

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And realize that everything is defined,

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or created

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by science.

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To understand the whole concept of science,

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you should know what a scientific theory is:

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"A scientific theory

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comprises a collection of concepts,

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including abstractions of observable phenomena,

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expressed as quantifiable properties,

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together with rules (called scientific laws)

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that express relationships

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between observations of such concepts."

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A scientific theory is constructed to conform to

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available empirical data about such observations,

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and is put forth as a principle or body of principles

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for explaining a class of phenomena.

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A scientific theory is totally different

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from any other theory,

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it is the most probable variant

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resulting from recent discoveries.

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Science is the best tool ever devised

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for understanding how the world works.

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Science is a very human form of knowledge.

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We are always at the brink of the known.

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Science is a collaborative enterprise

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spanning new generations.

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We remember those who prepared the way,

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seeing through them also.

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If you're scientifically literate

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the world looks very different to you,

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and that understanding empowers you.

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There's real poetry in the real world.

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Science is the poetry of reality.

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We can do science, and with it,

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we can improve our lives.

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There's real poetry in the real world.

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Science is the poetry of reality.

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The story of humans is the story of ideas

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that shine light into dark corners.

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Scientists love mysteries, they love not knowing.

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They don't feel frightened by not knowing things.

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I think it's much more interesting.

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There's a larger universal reality

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of which we are all a part.

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The further we probe into the universe,

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the more remarkable are the discoveries we make.

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The quest for the truth, in and of itself,

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is a story that's filled with insights.

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There's real poetry in the real world.

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Science is the poetry of reality.

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We can do science, and with it,

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we can improve our lives.

00:14:27.950 --> 00:14:30.600
There's real poetry in the real world.

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Science is the poetry of reality.

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The story of humans is the story of ideas

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that shine light into dark corners.

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From our lonely point in the cosmos,

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we have through the power of thought

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been able to peer back to a brief moment

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after the beginning of the universe.

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I think that science

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changes the way your mind works.

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To think a little more deeply about things.

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Science replaces private prejudice

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with publicly verifiable evidence.

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There's real poetry in the real world.

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Science is the poetry of reality.

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We can do science, and with it,

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we can improve our lives.

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Science is a great tool

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for understanding the surrounding world

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think of it as a magnifying glass

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through which you can see

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the reality of the world.