Can you hear me?
Yes,
I think you can hear me now,
but you don't see me.
That's because you have ears.
If you close your eyes and reach for the screen
you will know it's there.
You feel it through your skin.
If you have not been allowed to touch it,
at least you can smell it,
and after the hot plastic smell
you will realize that your monitor has to be there.
Luckily, you have a nose.
But, what if you taste it?
Well, it would be more difficult,
but eventually you'll taste the plastic,
because you have a tongue.
You understand the world around you,
I mean, everything that is around you,
through those five senses.
If you have ears,
you can hear.
If you have eyes,
you can see.
Through your skin,
you can feel.
The tongue will help you taste,
and if you have a nose, you can smell.
Eyes, ears, nose, tongue and skin are the "tools"
with which you were born.
Tools that help you understand the world around you.
But, how did you know all this?
Just because you noticed?
And how did we divide them into five senses?
The answer is science.
Because the world is so complicated
we use science to discover and define.
But, what is science?
"Investigation and study of nature
by observation and reasoning."
or "the sum of all knowledge
obtained through research."
Basically a sum of tests, numbers and letters,
which, all together can define.
But how?
Most people recognize marks as values,
and the best known groups are letters and numbers.
They are inventions which help us
to understand our environment.
To better understand how these marks
came into existence
let's see a brief history of mathematics.
Human beings, from our earliest beginnings,
have searched for solutions to basic problems.
Building homes, measuring space,
keeping track of seasons and counting objects.
Over thirty thousand years ago
early paleolithic people
kept track of the passing seasons
and the changes of weather for planting.
To represent the passing of time
they carved tally marks on cave walls
or slashed tallies on bones, wood or stone.
Each tally stood for one.
But this system was awkward
when it came to large amounts.
So symbols were eventually created
that stood for groups of objects.
Sumerian clay stones have been found
that date to the fourth millennium BC.
A small clay column was used for one,
a clay ball was used for ten,
and a large cone stood for sixty.
Written records from around 3300 BC show
that Babylonians inscribed amounts
on clay tablets with a reed.
They used a nail shape for ones,
and a V on its side for tens,
combining these symbols to write other numbers.
For example,
Babylonians wrote the number 19 as...
The ancient Egyptians used objects
from their everyday life as symbols.
A rod stood for one, a cattle hobble was ten,
a coiled rope was a hundred,
a lotus flower was a thousand and so on.
The number 19 was a cattle hobble and nine rods.
The early Romans created a number system
that we still see today.
Along with other symbols
they used an X for ten and an I for one.
By the middle ages
Romans were putting the I to the right of the X
for eleven and to the left for nine.
So they wrote 19 as XIX.
All these creative number systems
show groups of objects, as well as individual objects.
Some of the oldest human counting systems
rely on fingers and toes.
So they were based on ones, fivers, tens and twenties.
The Zulu word for six means
to take the thumb of the right hand.
Meaning that all the fingers on the left hand
had been added up and the other thumb was needed.
Other systems evolved from commerce.
The Yoruba, in Nigeria,
used cowry shells as currency
and developed an amazingly complex number system.
It was based on 20s
and on the operations of multiplication,
subtraction and addition.
For example:
they thought of 45 as (3 x 20) - 10 - 5.
Knots tied in cords and strings were used
for recording amounts by many cultures,
like the Persians.
The Incas used a more refined version
called the "quipu":
A thick cord held horizontally
from which hung knotted string.
The kind of knot the Incas used
along with the length and color of the cord
represented 1s, 10s, and 100s.
In today's world almost every industrial culture
uses the numeral 0 through 9.
But these symbols weren't invented
until the third century BC in India
and it took another 800 years
for the idea of 0 with place value to be constructed.
This big idea
dramatically changed the face of mathematics.
We humans have always shared with one another.
When early cultures shared their food and water
or wanted to divide their land
in ways that were fair and equal,
fractions gradually emerged
as symbols for these fair share situations.
The ancient Egyptians used unit fractions.
Fractions where the numerator is 1,
like 1/2, 1/3 and 1/5,
and would add and halve these fractions.
If they wanted to divide three loaves of bread equally
among five family members,
they'd first divide the first and second loaves
into thirds.
Then, they'd divide the third loaf into fifths.
Finally, they'd take the remaining one third
from the second loaf and divide that into five pieces.
They wrote this as 1/3, 1/5, 1/15.
Today we would represent this sharing
with the fraction 3/5.
3/5 of a loaf for each person,
or 3 loaves divided by 5 people.
The Sumerians and early Babylonians
invented a number system of fractions
based on 60, that we still use 4000 years later.
Our days have 60 minute hours
and 60 second minutes,
and our circles encompass 360 degrees.
Chinese societies used an abacus
with a system based on 10s, although it had no 0.
An early form of decimal fractions
came from the abacus.
For example:
3/5 would be 6 out of 10 on an abacus
The Chinese lovingly named the numerator "the son"
and the denominator "the mother".
It wasn't until the 12th century
that common fractions,
with the bar notation that we use today,
were invented.
Even then, these fractions weren't widely used
until the renaissance period, only 500 years ago.
Throughout history every culture around the globe
has created inventive ways to calculate.
To solve a problem, say... 12 x 15,
early Russian peasants
used a system of doubling and halving.
When an odd number halved resulted in a fraction,
they rounded down,
then they added the factors
associated with the odd multipliers.
Ancient Egyptians relied on a doubling procedure
until they produced enough groups.
Then they added these groups to find the answer.
Across Europe and Asia, during the middle ages,
the abacus was the handheld calculator of its day.
But only very few people knew how to use it,
usually wealthy merchants and money lenders.
By simply moving beads that each had place value
an abacus was a highly efficient way to compute.
Then, the great Arab mathematician al-KhwÄrizmÄŤ
introduced the Hindu Arabic numerals 0 through 9,
into North America and Europe
and created new procedures for computation.
These algorithms could be written onto paper.
Over the centuries learning the algorithms
became the whole mark of an education
as students were taught to compute
long columns of figures,
borrow and carry,
and do long division efficiently and reliably.
They could now keep records of these procedures
and check results.
Today complex calculations
are done with a handheld calculator.
This means students need the ability
to check the reasonableness of the answer
and to have a rich repertoire
of mental math strategies to do that.
Most simpler computations like 12 x 15
can be solved mentally using a variety of strategies.
As we journey through the rich
and vibrant history of mathematics
we can see how ideas and creations
grew out of our very human need
to solve the problems in our everyday lives.
Through time, the mathematical explorations
of men and women from around the globe,
have given us fascinating lenses
that help us to mathematically view
and make sense of our world.
Science is the collection of facts
arrived at by defining what we observe
and running tests to discover.
Mathematics, chemistry, and physics represent fixed
languages which are not subject to interpretation.
Languages used to describe what we observe and
to test those observations in order to prove them.
Think of DNA,
cells, galaxies,
fruits,
laptops,
air conditioning.
Think about cars,
food,
houses,
fauna,
flora.
Think about atoms,
body parts,
climate,
or the clothes you wear.
And realize that everything is defined,
or created
by science.
To understand the whole concept of science,
you should know what a scientific theory is:
"A scientific theory
comprises a collection of concepts,
including abstractions of observable phenomena,
expressed as quantifiable properties,
together with rules (called scientific laws)
that express relationships
between observations of such concepts."
A scientific theory is constructed to conform to
available empirical data about such observations,
and is put forth as a principle or body of principles
for explaining a class of phenomena.
A scientific theory is totally different
from any other theory,
it is the most probable variant
resulting from recent discoveries.
Science is the best tool ever devised
for understanding how the world works.
Science is a very human form of knowledge.
We are always at the brink of the known.
Science is a collaborative enterprise
spanning new generations.
We remember those who prepared the way,
seeing through them also.
If you're scientifically literate
the world looks very different to you,
and that understanding empowers you.
There's real poetry in the real world.
Science is the poetry of reality.
We can do science, and with it,
we can improve our lives.
There's real poetry in the real world.
Science is the poetry of reality.
The story of humans is the story of ideas
that shine light into dark corners.
Scientists love mysteries, they love not knowing.
They don't feel frightened by not knowing things.
I think it's much more interesting.
There's a larger universal reality
of which we are all a part.
The further we probe into the universe,
the more remarkable are the discoveries we make.
The quest for the truth, in and of itself,
is a story that's filled with insights.
There's real poetry in the real world.
Science is the poetry of reality.
We can do science, and with it,
we can improve our lives.
There's real poetry in the real world.
Science is the poetry of reality.
The story of humans is the story of ideas
that shine light into dark corners.
From our lonely point in the cosmos,
we have through the power of thought
been able to peer back to a brief moment
after the beginning of the universe.
I think that science
changes the way your mind works.
To think a little more deeply about things.
Science replaces private prejudice
with publicly verifiable evidence.
There's real poetry in the real world.
Science is the poetry of reality.
We can do science, and with it,
we can improve our lives.
Science is a great tool
for understanding the surrounding world
think of it as a magnifying glass
through which you can see
the reality of the world.