Advertisement
17:41
Transcript
0:16
First, a video.
0:24
Yes, it is a scrambled egg.
0:29
But as you look at it,
0:30
I hope you'll begin to feel
just slightly uneasy.
0:36
Because you may notice
that what's actually happening
0:40
is that the egg is unscrambling itself.
0:42
And you'll now see the yolk
and the white have separated.
0:44
And now they're going to be
poured back into the egg.
Advertisement
0:48
And we all know in our heart of hearts
0:50
that this is not the way
the universe works.
0:54
A scrambled egg is mush --
tasty mush -- but it's mush.
0:57
An egg is a beautiful, sophisticated thing
1:00
that can create even more
sophisticated things,
1:02
such as chickens.
1:04
And we know in our heart of hearts
1:06
that the universe does not travel
from mush to complexity.
1:10
In fact, this gut instinct
1:12
is reflected in one of the most
fundamental laws of physics,
Advertisement
1:15
the second law of thermodynamics,
or the law of entropy.
1:19
What that says basically
1:20
is that the general
tendency of the universe
1:24
is to move from order and structure
1:27
to lack of order, lack of structure --
1:30
in fact, to mush.
1:31
And that's why that video
feels a bit strange.
1:35
And yet, look around us.
1:39
What we see around us
is staggering complexity.
1:43
Eric Beinhocker estimates
that in New York City alone,
1:46
there are some 10 billion SKUs,
or distinct commodities, being traded.
1:50
That's hundreds of times
as many species as there are on Earth.
1:55
And they're being traded by a species
of almost seven billion individuals,
1:59
who are linked by trade,
travel, and the Internet
2:02
into a global system
of stupendous complexity.
2:07
So here's a great puzzle:
2:10
in a universe ruled
by the second law of thermodynamics,
2:14
how is it possible
2:16
to generate the sort
of complexity I've described,
2:19
the sort of complexity
represented by you and me
2:23
and the convention center?
2:26
Well, the answer seems to be,
2:28
the universe can create complexity,
2:31
but with great difficulty.
2:33
In pockets,
2:34
there appear
what my colleague, Fred Spier,
2:37
calls "Goldilocks conditions" --
2:39
not too hot, not too cold,
2:41
just right for the creation of complexity.
2:44
And slightly more complex things appear.
2:46
And where you have
slightly more complex things,
2:48
you can get slightly more complex things.
2:51
And in this way, complexity
builds stage by stage.
2:56
Each stage is magical
2:58
because it creates the impression
of something utterly new
3:02
appearing almost out of nowhere
in the universe.
3:04
We refer in big history to these moments
as threshold moments.
3:09
And at each threshold,
the going gets tougher.
3:12
The complex things get more fragile,
3:15
more vulnerable;
3:17
the Goldilocks conditions
get more stringent,
3:20
and it's more difficult
to create complexity.
3:24
Now, we, as extremely complex creatures,
3:28
desperately need to know this story
3:30
of how the universe creates complexity
despite the second law,
3:34
and why complexity means
vulnerability and fragility.
3:40
And that's the story
that we tell in big history.
3:43
But to do it, you have do something
3:45
that may, at first sight,
seem completely impossible.
3:48
You have to survey the whole
history of the universe.
3:52
So let's do it.
3:54
(Laughter)
3:56
Let's begin by winding the timeline back
3:59
13.7 billion years,
4:02
to the beginning of time.
4:12
Around us, there's nothing.
4:14
There's not even time or space.
4:18
Imagine the darkest,
emptiest thing you can
4:22
and cube it a gazillion times
and that's where we are.
4:25
And then suddenly,
4:28
bang!
4:29
A universe appears, an entire universe.
4:31
And we've crossed our first threshold.
4:33
The universe is tiny;
it's smaller than an atom.
4:35
It's incredibly hot.
4:37
It contains everything
that's in today's universe,
4:39
so you can imagine, it's busting.
4:41
And it's expanding at incredible speed.
4:44
And at first, it's just a blur,
4:46
but very quickly distinct things
begin to appear in that blur.
4:49
Within the first second,
4:51
energy itself shatters
into distinct forces
4:54
including electromagnetism and gravity.
4:57
And energy does something
else quite magical:
4:59
it congeals to form matter --
5:03
quarks that will create protons
5:05
and leptons that include electrons.
5:07
And all of that happens
in the first second.
5:09
Now we move forward 380,000 years.
5:14
That's twice as long as humans
have been on this planet.
5:17
And now simple atoms appear
of hydrogen and helium.
5:23
Now I want to pause for a moment,
5:25
380,000 years after the origins
of the universe,
5:28
because we actually know quite a lot
about the universe at this stage.
5:32
We know above all
that it was extremely simple.
5:35
It consisted of huge clouds
of hydrogen and helium atoms,
5:39
and they have no structure.
5:41
They're really a sort of cosmic mush.
5:44
But that's not completely true.
5:46
Recent studies
5:48
by satellites such as the WMAP satellite
5:51
have shown that, in fact,
5:52
there are just tiny differences
in that background.
5:55
What you see here,
5:57
the blue areas are about a thousandth
of a degree cooler
6:01
than the red areas.
6:03
These are tiny differences,
6:04
but it was enough
for the universe to move on
6:06
to the next stage of building complexity.
6:08
And this is how it works.
6:10
Gravity is more powerful
where there's more stuff.
6:15
So where you get slightly denser areas,
6:18
gravity starts compacting clouds
of hydrogen and helium atoms.
6:22
So we can imagine the early universe
breaking up into a billion clouds.
6:25
And each cloud is compacted,
6:27
gravity gets more powerful
as density increases,
6:30
the temperature begins to rise
at the center of each cloud,
6:33
and then, at the center,
6:34
the temperature crosses
the threshold temperature
6:37
of 10 million degrees,
6:39
protons start to fuse,
6:41
there's a huge release of energy,
6:44
and --
6:45
bam!
6:46
We have our first stars.
6:48
From about 200 million years
after the Big Bang,
6:52
stars begin to appear
all through the universe,
6:56
billions of them.
6:57
And the universe is now
significantly more interesting
7:00
and more complex.
7:03
Stars will create
the Goldilocks conditions
7:06
for crossing two new thresholds.
7:08
When very large stars die,
7:11
they create temperatures so high
7:13
that protons begin to fuse
in all sorts of exotic combinations,
7:17
to form all the elements
of the periodic table.
7:20
If, like me, you're wearing a gold ring,
7:22
it was forged in a supernova explosion.
7:25
So now the universe
is chemically more complex.
7:29
And in a chemically more complex universe,
7:31
it's possible to make more things.
7:33
And what starts happening
is that, around young suns,
7:37
young stars,
7:39
all these elements combine,
they swirl around,
7:41
the energy of the star stirs them around,
7:44
they form particles, they form snowflakes,
they form little dust motes,
7:49
they form rocks, they form asteroids,
7:51
and eventually,
they form planets and moons.
7:53
And that is how our
solar system was formed,
7:56
four and a half billion years ago.
8:00
Rocky planets like our Earth
are significantly more complex than stars
8:05
because they contain
a much greater diversity of materials.
8:08
So we've crossed a fourth
threshold of complexity.
8:12
Now, the going gets tougher.
8:16
The next stage introduces entities
that are significantly more fragile,
8:20
significantly more vulnerable,
8:22
but they're also much more creative
8:25
and much more capable
of generating further complexity.
8:28
I'm talking, of course,
about living organisms.
8:32
Living organisms are created by chemistry.
8:34
We are huge packages of chemicals.
8:38
So, chemistry is dominated
by the electromagnetic force.
8:41
That operates over smaller
scales than gravity,
8:43
which explains why you and I
are smaller than stars or planets.
8:48
Now, what are the ideal
conditions for chemistry?
8:50
What are the Goldilocks conditions?
8:52
Well, first, you need energy,
8:55
but not too much.
8:56
In the center of a star,
there's so much energy
8:58
that any atoms that combine
will just get busted apart again.
9:02
But not too little.
9:03
In intergalactic space,
9:04
there's so little energy
that atoms can't combine.
9:08
What you want is just the right amount,
9:10
and planets, it turns out, are just right,
9:12
because they're close to stars,
but not too close.
9:15
You also need a great diversity
of chemical elements,
9:19
and you need liquids, such as water.
9:22
Why?
9:23
Well, in gases, atoms move
past each other so fast
9:27
that they can't hitch up.
9:28
In solids,
9:30
atoms are stuck together, they can't move.
9:33
In liquids,
9:35
they can cruise and cuddle
9:38
and link up to form molecules.
9:41
Now, where do you find
such Goldilocks conditions?
9:43
Well, planets are great,
9:45
and our early Earth was almost perfect.
9:50
It was just the right
distance from its star
9:52
to contain huge oceans of liquid water.
9:54
And deep beneath those oceans,
9:56
at cracks in the Earth's crust,
9:58
you've got heat seeping up
from inside the Earth,
10:01
and you've got a great
diversity of elements.
10:03
So at those deep oceanic vents,
10:05
fantastic chemistry began to happen,
10:08
and atoms combined in all sorts
of exotic combinations.
10:12
But of course, life is more
than just exotic chemistry.
10:17
How do you stabilize those huge molecules
10:20
that seem to be viable?
10:22
Well, it's here that life introduces
an entirely new trick.
10:28
You don't stabilize the individual;
10:30
you stabilize the template,
10:32
the thing that carries information,
10:35
and you allow the template to copy itself.
10:37
And DNA, of course,
is the beautiful molecule
10:40
that contains that information.
10:42
You'll be familiar
with the double helix of DNA.
10:45
Each rung contains information.
10:48
So, DNA contains information
about how to make living organisms.
10:53
And DNA also copies itself.
10:55
So, it copies itself
10:56
and scatters the templates
through the ocean.
10:59
So the information spreads.
11:01
Notice that information
has become part of our story.
11:04
The real beauty of DNA though
is in its imperfections.
11:07
As it copies itself,
once in every billion rungs,
11:11
there tends to be an error.
11:13
And what that means
is that DNA is, in effect, learning.
11:18
It's accumulating new ways
of making living organisms
11:21
because some of those errors work.
11:23
So DNA's learning
11:24
and it's building greater
diversity and greater complexity.
11:27
And we can see this happening
over the last four billion years.
11:30
For most of that time of life on Earth,
11:33
living organisms have been
relatively simple --
11:35
single cells.
11:36
But they had great diversity,
and, inside, great complexity.
11:40
Then from about 600
to 800 million years ago,
11:43
multi-celled organisms appear.
11:45
You get fungi, you get fish,
11:48
you get plants,
11:49
you get amphibia, you get reptiles,
11:52
and then, of course,
you get the dinosaurs.
11:55
And occasionally, there are disasters.
11:59
Sixty-five million years ago,
12:01
an asteroid landed on Earth
12:03
near the Yucatan Peninsula,
12:05
creating conditions equivalent
to those of a nuclear war,
12:08
and the dinosaurs were wiped out.
12:11
Terrible news for the dinosaurs,
12:14
but great news
for our mammalian ancestors,
12:18
who flourished
12:19
in the niches left empty by the dinosaurs.
12:22
And we human beings are part
of that creative evolutionary pulse
12:28
that began 65 million years ago
12:30
with the landing of an asteroid.
12:33
Humans appeared about 200,000 years ago.
12:36
And I believe we count
as a threshold in this great story.
12:40
Let me explain why.
12:42
We've seen that DNA learns in a sense,
12:45
it accumulates information.
12:47
But it is so slow.
12:50
DNA accumulates information
through random errors,
12:53
some of which just happen to work.
12:56
But DNA had actually generated
a faster way of learning:
12:59
it had produced organisms with brains,
13:01
and those organisms
can learn in real time.
13:05
They accumulate information, they learn.
13:07
The sad thing is, when they die,
13:10
the information dies with them.
13:12
Now what makes humans different
is human language.
13:16
We are blessed with a language,
a system of communication,
13:19
so powerful and so precise
13:21
that we can share what we've learned
with such precision
13:25
that it can accumulate
in the collective memory.
13:28
And that means
13:29
it can outlast the individuals
who learned that information,
13:33
and it can accumulate
from generation to generation.
13:36
And that's why, as a species,
we're so creative and so powerful,
13:40
and that's why we have a history.
13:43
We seem to be the only species
in four billion years
13:46
to have this gift.
13:48
I call this ability collective learning.
13:51
It's what makes us different.
13:53
We can see it at work
in the earliest stages of human history.
13:57
We evolved as a species
in the savanna lands of Africa,
14:01
but then you see humans migrating
into new environments,
14:04
into desert lands, into jungles,
14:06
into the Ice Age tundra of Siberia --
14:09
tough, tough environment --
14:10
into the Americas, into Australasia.
14:13
Each migration involved learning --
14:15
learning new ways of exploiting
the environment,
14:17
new ways of dealing
with their surroundings.
14:19
Then 10,000 years ago,
14:21
exploiting a sudden
change in global climate
14:24
with the end of the last ice age,
14:26
humans learned to farm.
14:28
Farming was an energy bonanza.
14:31
And exploiting that energy,
human populations multiplied.
14:34
Human societies got larger,
denser, more interconnected.
14:39
And then from about 500 years ago,
14:42
humans began to link up globally
14:44
through shipping, through trains,
14:46
through telegraph, through the Internet,
14:49
until now we seem to form
a single global brain
14:54
of almost seven billion individuals.
14:56
And that brain is learning at warp speed.
15:00
And in the last 200 years,
something else has happened.
15:03
We've stumbled on another energy bonanza
15:05
in fossil fuels.
15:07
So fossil fuels and collective
learning together
15:09
explain the staggering complexity
we see around us.
15:16
So --
15:18
Here we are,
15:20
back at the convention center.
15:21
We've been on a journey,
a return journey, of 13.7 billion years.
15:26
I hope you agree this is a powerful story.
15:29
And it's a story in which humans
play an astonishing and creative role.
15:34
But it also contains warnings.
15:37
Collective learning is a very,
very powerful force,
15:41
and it's not clear
that we humans are in charge of it.
15:47
I remember very vividly
as a child growing up in England,
15:50
living through the Cuban Missile Crisis.
15:52
For a few days, the entire biosphere
15:56
seemed to be on the verge of destruction.
15:59
And the same weapons are still here,
16:02
and they are still armed.
16:05
If we avoid that trap,
others are waiting for us.
16:08
We're burning fossil fuels at such a rate
16:11
that we seem to be undermining
the Goldilocks conditions
16:14
that made it possible
for human civilizations
16:16
to flourish over the last 10,000 years.
16:20
So what big history can do
16:22
is show us the nature
of our complexity and fragility
16:26
and the dangers that face us,
16:28
but it can also show us
our power with collective learning.
16:32
And now, finally --
16:35
this is what I want.
16:39
I want my grandson, Daniel,
16:42
and his friends and his generation,
16:45
throughout the world,
16:47
to know the story of big history,
16:49
and to know it so well
16:52
that they understand
both the challenges that face us
16:55
and the opportunities that face us.
16:58
And that's why a group of us
17:00
are building a free, online syllabus
17:03
in big history
17:04
for high-school students
throughout the world.
17:07
We believe that big history
17:09
will be a vital
intellectual tool for them,
17:12
as Daniel and his generation
17:15
face the huge challenges
17:17
and also the huge opportunities
17:19
ahead of them at this threshold moment
17:23
in the history of our beautiful planet.
17:26
I thank you for your attention.
17:28
(Applause)
— end of transcript —
Advertisement
More from TED
11:44
Celeste Headlee: 10 ways to have a better conversation | TED
TED
20:32
This could be why you're depressed or anxious | Johann Hari | TED
TED
10:46
The secrets of learning a new language | Lýdia Machová | TED
TED
12:54
How to Make Learning as Addictive as Social Media | Duolingo's Luis Von Ahn | TED
TED
