Juan Enriquez00:02
Here's a question that matters.
00:04
[Is it ethical to evolve the human body?]
00:06
Because we're beginning to get all the tools together to evolve ourselves. And we can evolve bacteria and we can evolve plantsand we can evolve animals, and we're now reaching a point where we really have to ask, is it really ethical and do we want to evolve human beings? And as you're thinking about that, let me talk about that in the context of prosthetics, prosthetics past, present, future.
00:30
So this is the iron hand that belonged to one of the German counts. Loved to fight, lost his arm in one of these battles. No problem, he just made a suit of armor, put it on, perfect prosthetic. That's where the concept of ruling with an iron fist comes from.
00:49
And of course these prosthetics have been getting more and more useful, more and more modern. You can hold soft-boiled eggs.You can have all types of controls, and as you're thinking about that, there are wonderful people like Hugh Herr who have been building absolutely extraordinary prosthetics. So the wonderful Aimee Mullins will go out and say, how tall do I want to be tonight?Or Hugh will say what type of cliff do I want to climb? Or does somebody want to run a marathon, or does somebody want to ballroom dance? And as you adapt these things, the interesting thing about prosthetics is they've been coming inside the body. So these external prosthetics have now become artificial knees. They've become artificial hips. And then they've evolved further to become not just nice to have but essential to have.
01:35
So when you're talking about a heart pacemaker as a prosthetic, you're talking about something that isn't just, "I'm missing my leg," it's, "if I don't have this, I can die." And at that point, a prosthetic becomes a symbiotic relationship with the human body.
01:52
And four of the smartest people that I've ever met -- Ed Boyden, Hugh Herr, Joe Jacobson, Bob Lander -- are working on a Center for Extreme Bionics. And the interesting thing of what you're seeing here is these prosthetics now get integrated into the bone.They get integrated into the skin. They get integrated into the muscle. And one of the other sides of Ed is he's been thinking about how to connect the brain using light or other mechanisms directly to things like these prosthetics. And if you can do that, then you can begin changing fundamental aspects of humanity. So how quickly you react to something depends on the diameter of a nerve.And of course, if you have nerves that are external or prosthetic, say with light or liquid metal, then you can increase that diameterand you could even increase it theoretically to the point where, as long as you could see the muzzle flash, you could step out of the way of a bullet. Those are the order of magnitude of changes you're talking about.
02:56
This is a fourth sort of level of prosthetics. These are Phonak hearing aids, and the reason why these are so interesting is because they cross the threshold from where prosthetics are something for somebody who is "disabled" and they become something that somebody who is "normal" might want to actually have, because what this prosthetic does, which is really interesting, is not only does it help you hear, you can focus your hearing, so it can hear the conversation going on over there. You can have superhearing.You can have hearing in 360 degrees. You can have white noise. You can record, and oh, by the way, they also put a phone into this. So this functions as your hearing aid and also as your phone. And at that point, somebody might actually want to have a prosthetic voluntarily.
03:42
All of these thousands of loosely connected little pieces are coming together, and it's about time we ask the question, how do we want to evolve human beings over the next century or two? And for that we turn to a great philosopher who was a very smart man despite being a Yankee fan.
04:00
04:02
And Yogi Berra used to say, of course, that it's very tough to make predictions, especially about the future.
04:08
04:09
So instead of making a prediction about the future to begin with, let's take what's happening in the present with people like Tony Atala, who is redesigning 30-some-odd organs. And maybe the ultimate prosthetic isn't having something external, titanium.Maybe the ultimate prosthetic is take your own gene code, remake your own body parts, because that's a whole lot more effective than any kind of a prosthetic. But while you're at it, then you can take the work of Craig Venter and Ham Smith. And one of the things that we've been doing is trying to figure out how to reprogram cells. And if you can reprogram a cell, then you can change the cells in those organs. So if you can change the cells in those organs, maybe you make those organs more radiation-resistant.Maybe you make them absorb more oxygen. Maybe you make them more efficient to filter out stuff that you don't want in your body.
04:59
And over the last few weeks, George Church has been in the news a lot because he's been talking about taking one of these programmable cells and inserting an entire human genome into that cell. And once you can insert an entire human genome into a cell, then you begin to ask the question, would you want to enhance any of that genome? Do you want to enhance a human body?How would you want to enhance a human body? Where is it ethical to enhance a human body and where is it not ethical to enhance a human body? And all of a sudden, what we're doing is we've got this multidimensional chess board where we can change human genetics by using viruses to attack things like AIDS, or we can change the gene code through gene therapy to do away with some hereditary diseases, or we can change the environment, and change the expression of those genes in the epigenome and pass that on to the next generations. And all of a sudden, it's not just one little bit, it's all these stacked little bitsthat allow you to take little portions of it until all the portions coming together lead you to something that's very different.
06:09
And a lot of people are very scared by this stuff. And it does sound scary, and there are risks to this stuff. So why in the world would you ever want to do this stuff? Why would we really want to alter the human body in a fundamental way?
06:25
The answer lies in part with Lord Rees, astronomer royal of Great Britain. And one of his favorite sayings is the universe is 100 percent malevolent. So what does that mean? It means if you take any one of your bodies at random, drop it anywhere in the universe, drop it in space, you die. Drop it on the Sun, you die. Drop it on the surface of Mercury, you die. Drop it near a supernova, you die. But fortunately, it's only about 80 percent effective.
06:54
So as a great physicist once said, there's these little upstream eddies of biology that create order in this rapid torrent of entropy.So as the universe dissipates energy, there's these upstream eddies that create biological order. Now, the problem with eddies is,they tend to disappear. They shift. They move in rivers. And because of that, when an eddy shifts, when the Earth becomes a snowball, when the Earth becomes very hot, when the Earth gets hit by an asteroid, when you have supervolcanoes, when you have solar flares, when you have potentially extinction-level events like the next election --
07:38
07:41
then all of a sudden, you can have periodic extinctions. And by the way, that's happened five times on Earth, and therefore it is very likely that the human species on Earth is going to go extinct someday. Not next week, not next month, maybe in November, but maybe 10,000 years after that. As you're thinking of the consequence of that, if you believe that extinctions are common and natural and normal and occur periodically, it becomes a moral imperative to diversify our species.
08:14
And it becomes a moral imperative because it's going to be really hard to live on Mars if we don't fundamentally modify the human body. Right? You go from one cell, mom and dad coming together to make one cell, in a cascade to 10 trillion cells. We don't know, if you change the gravity substantially, if the same thing will happen to create your body. We do know that if you expose our bodies as they currently are to a lot of radiation, we will die. So as you're thinking of that, you have to really redesign things just to get to Mars. Forget about the moons of Neptune or Jupiter.
08:53
And to borrow from Nikolai Kardashev, let's think about life in a series of scales. So Life One civilization is a civilization that begins to alter his or her looks. And we've been doing that for thousands of years. You've got tummy tucks and you've got this and you've got that. You alter your looks, and I'm told that not all of those alterations take place for medical reasons.
09:16
09:18
09:20
A Life Two civilization is a different civilization. A Life Two civilization alters fundamental aspects of the body. So you put human growth hormone in, the person grows taller, or you put x in and the person gets fatter or loses metabolism or does a whole series of things, but you're altering the functions in a fundamental way.
09:41
To become an intrasolar civilization, we're going to have to create a Life Three civilization, and that looks very different from what we've got here. Maybe you splice in Deinococcus radiodurans so that the cells can resplice after a lot of exposure to radiation.Maybe you breathe by having oxygen flow through your blood instead of through your lungs. But you're talking about really radical redesigns, and one of the interesting things that's happened in the last decade is we've discovered a whole lot of planets out there.And some of them may be Earth-like. The problem is, if we ever want to get to these planets, the fastest human objects -- Juno and Voyager and the rest of this stuff -- take tens of thousands of years to get from here to the nearest solar system. So if you want to start exploring beaches somewhere else, or you want to see two-sun sunsets, then you're talking about something that is very different, because you have to change the timescale and the body of humans in ways which may be absolutely unrecognizable.And that's a Life Four civilization.
10:53
Now, we can't even begin to imagine what that might look like, but we're beginning to get glimpses of instruments that might take us even that far. And let me give you two examples.
11:04
So this is the wonderful Floyd Romesberg, and one of the things that Floyd's been doing is he's been playing with the basic chemistry of life. So all life on this planet is made in ATCGs, the four letters of DNA. All bacteria, all plants, all animals, all humans, all cows, everything else. And what Floyd did is he changed out two of those base pairs, so it's ATXY. And that means that you now have a parallel system to make life, to make babies, to reproduce, to evolve, that doesn't mate with most things on Earth or in fact maybe with nothing on Earth. Maybe you make plants that are immune to all bacteria. Maybe you make plants that are immune to all viruses. But why is that so interesting? It means that we are not a unique solution. It means you can create alternate chemistries to us that could be chemistries adaptable to a very different planet that could create life and heredity.
12:08
The second experiment, or the other implication of this experiment, is that all of you, all life is based on 20 amino acids. If you don't substitute two amino acids, if you don't say ATXY, if you say ATCG + XY, then you go from 20 building blocks to 172, and all of a sudden you've got 172 building blocks of amino acids to build life-forms in very different shapes.
12:37
The second experiment to think about is a really weird experiment that's been taking place in China. So this guy has been transplanting hundreds of mouse heads. Right? And why is that an interesting experiment? Well, think of the first heart transplants.One of the things they used to do is they used to bring in the wife or the daughter of the donor so the donee could tell the doctors,"Do you recognize this person? Do you love this person? Do you feel anything for this person?" We laugh about that today. We laugh because we know the heart is a muscle, but for hundreds of thousands of years, or tens of thousands of years, "I gave her my heart. She took my heart. She broke my heart." We thought this was emotion and we thought maybe emotions were transplanted with the heart. Nope.
13:26
So how about the brain? Two possible outcomes to this experiment. If you can get a mouse that is functional, then you can see, is the new brain a blank slate? And boy, does that have implications. Second option: the new mouse recognizes Minnie Mouse. The new mouse remembers what it's afraid of, remembers how to navigate the maze, and if that is true, then you can transplant memory and consciousness. And then the really interesting question is, if you can transplant this, is the only input-output mechanism this down here? Or could you transplant that consciousness into something that would be very different, that would last in space, that would last tens of thousands of years, that would be a completely redesigned body that could hold consciousness for a long, long period of time?
14:26
And let's come back to the first question: Why would you ever want to do that? Well, I'll tell you why. Because this is the ultimate selfie.
14:36
14:38
This is taken from six billion miles away, and that's Earth. And that's all of us. And if that little thing goes, all of humanity goes. And the reason you want to alter the human body is because you eventually want a picture that says, that's us, and that's us, and that's us, because that's the way humanity survives long-term extinction. And that's the reason why it turns out it's actually unethical not to evolve the human body even though it can be scary, even though it can be challenging, but it's what's going to allow us to explore, live and get to places we can't even dream of today, but which our great-great-great-great- grandchildren might someday.
15:25
15:26
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Every weekend for as long as I can remember, my father would get up on a Saturday, put on a worn sweatshirt and he'd scrape away at the squeaky old wheel of a house that we lived in. I wouldn't even call it restoration; it was a ritual, catharsis. He would spend all year scraping paint with this old heat gun and a spackle knife, and then he would repaint where he scraped, only to begin again the following year. Scraping and re-scraping, painting and repainting: the work of an old house is never meant to be done.
00:37
The day my father turned 52, I got a phone call. My mother was on the line to tell me that doctors had found a lump in his stomach -- terminal cancer, she told me, and he had been given only three weeks to live.
00:52
I immediately moved home to Poughkeepsie, New York, to sit with my father on death watch, not knowing what the next days would bring us. To keep myself distracted, I rolled up my sleeves, and I went about finishing what he could now no longer complete -- the restoration of our old home.
01:11
When that looming three-week deadline came and then went, he was still alive. And at three months, he joined me. We gutted and repainted the interior. At six months, the old windows were refinished, and at 18 months, the rotted porch was finally replaced.
01:31
And there was my father, standing with me outside, admiring a day's work, hair on his head, fully in remission, when he turned to me and he said, "You know, Michael, this house saved my life."
01:46
So the following year, I decided to go to architecture school.
01:52
01:53
But there, I learned something different about buildings. Recognition seemed to come to those who prioritized novel and sculptural forms, like ribbons, or ... pickles?
02:06
02:10
And I think this is supposed to be a snail.
02:14
Something about this bothered me. Why was it that the best architects, the greatest architecture -- all beautiful and visionary and innovative -- is also so rare, and seems to serve so very few? And more to the point: With all of this creative talent, what more could we do?
02:36
Just as I was about to start my final exams, I decided to take a break from an all-nighter and go to a lecture by Dr. Paul Farmer,a leading health activist for the global poor. I was surprised to hear a doctor talking about architecture. Buildings are making people sicker, he said, and for the poorest in the world, this is causing epidemic-level problems. In this hospital in South Africa,patients that came in with, say, a broken leg, to wait in this unventilated hallway, walked out with a multidrug-resistant strand of tuberculosis. Simple designs for infection control had not been thought about, and people had died because of it.
03:18
"Where are the architects?" Paul said. If hospitals are making people sicker, where are the architects and designers to help us build and design hospitals that allow us to heal?
03:32
That following summer, I was in the back of a Land Rover with a few classmates, bumping over the mountainous hillside of Rwanda. For the next year, I'd be living in Butaro in this old guesthouse, which was a jail after the genocide. I was there to design and build a new type of hospital with Dr. Farmer and his team. If hallways are making patients sicker, what if we could design a hospital that flips the hallways on the outside, and makes people walk in the exterior? If mechanical systems rarely work, what if we could design a hospital that could breathe through natural ventilation, and meanwhile reduce its environmental footprint?
04:14
And what about the patients' experience? Evidence shows that a simple view of nature can radically improve health outcomes,So why couldn't we design a hospital where every patient had a window with a view? Simple, site-specific designs can make a hospital that heals.
04:32
Designing it is one thing; getting it built, we learned, is quite another.
04:37
We worked with Bruce Nizeye, a brilliant engineer, and he thought about construction differently than I had been taught in school. When we had to excavate this enormous hilltop and a bulldozer was expensive and hard to get to site, Bruce suggested doing it by hand, using a method in Rwanda called "Ubudehe," which means "community works for the community." Hundreds of people came with shovels and hoes, and we excavated that hill in half the time and half the cost of that bulldozer. Instead of importing furniture, Bruce started a guild, and he brought in master carpenters to train others in how to make furniture by hand. And on this job site, 15 years after the Rwandan genocide, Bruce insisted that we bring on labor from all backgrounds, and that half of them be women.
05:30
Bruce was using the process of building to heal, not just for those who were sick, but for the entire community as a whole. We call this the locally fabricated way of building, or "lo-fab," and it has four pillars: hire locally, source regionally, train where you can and most importantly, think about every design decision as an opportunity to invest in the dignity of the places where you serve. Think of it like the local food movement, but for architecture. And we're convinced that this way of building can be replicated across the world, and change the way we talk about and evaluate architecture.
06:15
Using the lo-fab way of building, even aesthetic decisions can be designed to impact people's lives. In Butaro, we chose to use a local volcanic stone found in abundance within the area, but often considered a nuisance by farmers, and piled on the side of the road. We worked with these masons to cut these stones and form them into the walls of the hospital. And when they began on this corner and wrapped around the entire hospital, they were so good at putting these stones together, they asked us if they could take down the original wall and rebuild it. And you see what is possible. It's beautiful. And the beauty, to me, comes from the fact that I know that hands cut these stones, and they formed them into this thick wall, made only in this place with rocks from this soil.
07:08
When you go outside today and you look at your built world, ask not only: "What is the environmental footprint?" -- an important question -- but what if we also asked, "What is the human handprint of those who made it?"
07:23
We started a new practice based around these questions, and we tested it around the world. Like in Haiti, where we asked if a new hospital could help end the epidemic of cholera. In this 100-bed hospital, we designed a simple strategy to clean contaminated medical waste before it enters the water table, and our partners at Les Centres GHESKIO are already saving lives because of it.
07:49
Or Malawi: we asked if a birthing center could radically reduce maternal and infant mortality. Malawi has one of the highest rates of maternal and infant death in the world. Using a simple strategy to be replicated nationally, we designed a birthing center that would attract women and their attendants to come to the hospital earlier and therefore have safer births.
08:12
Or in the Congo, where we asked if an educational center could also be used to protect endangered wildlife. Poaching for ivory and bushmeat is leading to global epidemic, disease transfer and war. In one of the hardest-to-reach places in the world, we used the mud and the dirt and the wood around us to construct a center that would show us ways to protect and conserve our rich biodiversity.
08:37
Even here in the US, we were asked to rethink the largest university for the deaf and hard of hearing in the world. The deaf community, through sign language, shows us the power of visual communication. We designed a campus that would awaken the ways in which we as humans all communicate, both verbally and nonverbally.
08:57
And even in Poughkeepsie, my hometown, we thought about old industrial infrastructure. We wondered: Could we use arts and culture and design to revitalize this city and other Rust Belt cities across our nation, and turn them into centers for innovation and growth? In each of these projects, we asked a simple question: What more can architecture do? And by asking that question, we were forced to consider how we could create jobs, how we could source regionally and how we could invest in the dignity of the communities in which we serve.
09:35
I have learned that architecture can be a transformative engine for change.
09:45
About a year ago, I read an article about a tireless and intrepid civil rights leader named Bryan Stevenson.
09:56
10:02
And Bryan had a bold architectural vision. He and his team had been documenting the over 4,000 lynchings of African-Americans that have happened in the American South. And they had a plan to mark every county where these lynchings occurred, and build a national memorial to the victims of lynching in Montgomery, Alabama.
10:25
Countries like Germany and South Africa and, of course, Rwanda, have found it necessary to build memorials to reflect on the atrocities of their past, in order to heal their national psyche. We have yet to do this in the United States.
10:44
So I sent a cold email to info@equaljusticeintiative.org: "Dear Bryan," it said, "I think your building project is maybe the most important project we could do in America and could change the way we think about racial injustice. By any chance, do you know who will design it?"
11:06
11:08
Surprisingly, shockingly, Bryan got right back to me, and invited me down to meet with his team and talk to them. Needless to say, I canceled all my meetings and I jumped on a plane to Montgomery, Alabama. When I got there, Bryan and his team picked me up, and we walked around the city. And they took the time to point out the many markers that have been placed all over the city to the history of the Confederacy, and the very few that mark the history of slavery.
11:38
And then he walked me to a hill. It overlooked the whole city. He pointed out the river and the train tracks where the largest domestic slave-trading port in America had once prospered. And then to the Capitol rotunda, where George Wallace had stood on its steps and proclaimed, "Segregation forever." And then to the very hill below us. He said, "Here we will build a new memorial that will change the identity of this city and of this nation."
12:06
Our two teams have worked together over the last year to design this memorial. The memorial will take us on a journey through a classical, almost familiar building type, like the Parthenon or the colonnade at the Vatican. But as we enter, the ground drops below us and our perception shifts, where we realize that these columns evoke the lynchings, which happened in the public square. And as we continue, we begin to understand the vast number of those who have yet to be put to rest. Their names will be engraved on the markers that hang above us. And just outside will be a field of identical columns. But these are temporary columns, waiting in purgatory, to be placed in the very counties where these lynchings occurred. Over the next few years, this site will bear witness, as each of these markers is claimed and visibly placed in those counties. Our nation will begin to heal from over a century of silence.
13:23
When we think about how it should be built, we were reminded of Ubudehe, the building process we learned about in Rwanda.We wondered if we could fill those very columns with the soil from the sites of where these killings occurred. Brian and his team have begun collecting that soil and preserving it in individual jars with family members, community leaders and descendants. The act of collecting soil itself has lead to a type of spiritual healing. It's an act of restorative justice.
14:00
As one EJI team member noted in the collection of the soil from where Will McBride was lynched, "If Will McBride left one drop of sweat, one drop of blood, one hair follicle -- I pray that I dug it up, and that his whole body would be at peace."
14:22
We plan to break ground on this memorial later this year, and it will be a place to finally speak of the unspeakable acts that have scarred this nation.
14:34
14:45
When my father told me that day that this house -- our house -- had saved his life, what I didn't know was that he was referring to a much deeper relationship between architecture and ourselves. Buildings are not simply expressive sculptures. They make visible our personal and our collective aspirations as a society. Great architecture can give us hope. Great architecture can heal.
15:16
15:17
00:00
First, a video. Yes, it is a scrambled egg. But as you look at it, I hope you'll begin to feel just slightly uneasy. Because you may notice that what's actually happening is that the egg is unscrambling itself. And you'll now see the yolk and the white have separated. And now they're going to be poured back into the egg. And we all know in our heart of hearts that this is not the way the universe works. A scrambled egg is mush -- tasty mush -- but it's mush. An egg is a beautiful, sophisticated thing that can create even more sophisticated things, such as chickens. And we know in our heart of hearts that the universe does not travel from mush to complexity. In fact, this gut instinct is reflected in one of the most fundamental laws of physics, the second law of thermodynamics, or the law of entropy. What that says basically is that the general tendency of the universe is to move from order and structure to lack of order, lack of structure -- in fact, to mush. And that's why that video feels a bit strange.
01:20
And yet, look around us. What we see around us is staggering complexity. Eric Beinhocker estimates that in New York City alone, there are some 10 billion SKUs, or distinct commodities, being traded. That's hundreds of times as many species as there are on Earth. And they're being traded by a species of almost seven billion individuals, who are linked by trade, travel, and the Internet into a global system of stupendous complexity.
01:52
So here's a great puzzle: in a universe ruled by the second law of thermodynamics, how is it possible to generate the sort of complexity I've described, the sort of complexity represented by you and me and the convention center? Well, the answer seems to be, the universe can create complexity, but with great difficulty. In pockets, there appear what my colleague, Fred Spier, calls "Goldilocks conditions" -- not too hot, not too cold, just right for the creation of complexity. And slightly more complex things appear. And where you have slightly more complex things, you can get slightly more complex things. And in this way, complexity builds stage by stage. Each stage is magical because it creates the impression of something utterly newappearing almost out of nowhere in the universe. We refer in big history to these moments as threshold moments. And at each threshold, the going gets tougher. The complex things get more fragile, more vulnerable; the Goldilocks conditions get more stringent, and it's more difficult to create complexity.
03:09
Now, we, as extremely complex creatures, desperately need to know this story of how the universe creates complexity despite the second law, and why complexity means vulnerability and fragility. And that's the story that we tell in big history. But to do it, you have do something that may, at first sight, seem completely impossible. You have to survey the whole history of the universe. So let's do it.
03:39
03:40
Let's begin by winding the timeline back 13.7 billion years, to the beginning of time.
03:57
Around us, there's nothing. There's not even time or space. Imagine the darkest, emptiest thing you can and cube it a gazillion times and that's where we are. And then suddenly, bang! A universe appears, an entire universe. And we've crossed our first threshold. The universe is tiny; it's smaller than an atom. It's incredibly hot. It contains everything that's in today's universe, so you can imagine, it's busting. And it's expanding at incredible speed. And at first, it's just a blur, but very quickly distinct things begin to appear in that blur. Within the first second, energy itself shatters into distinct forces including electromagnetism and gravity. And energy does something else quite magical: it congeals to form matter -- quarks that will create protons and leptons that include electrons. And all of that happens in the first second.
04:54
Now we move forward 380,000 years. That's twice as long as humans have been on this planet. And now simple atoms appear of hydrogen and helium. Now I want to pause for a moment, 380,000 years after the origins of the universe, because we actually know quite a lot about the universe at this stage. We know above all that it was extremely simple. It consisted of huge clouds of hydrogen and helium atoms, and they have no structure. They're really a sort of cosmic mush. But that's not completely true. Recent studies by satellites such as the WMAP satellite have shown that, in fact, there are just tiny differences in that background. What you see here, the blue areas are about a thousandth of a degree cooler than the red areas. These are tiny differences, but it was enough for the universe to move on to the next stage of building complexity.
05:53
And this is how it works. Gravity is more powerful where there's more stuff. So where you get slightly denser areas, gravity starts compacting clouds of hydrogen and helium atoms. So we can imagine the early universe breaking up into a billion clouds. And each cloud is compacted, gravity gets more powerful as density increases, the temperature begins to rise at the center of each cloud, and then, at the center, the temperature crosses the threshold temperature of 10 million degrees, protons start to fuse, there's a huge release of energy, and -- bam! We have our first stars. From about 200 million years after the Big Bang, stars begin to appear all through the universe, billions of them. And the universe is now significantly more interesting and more complex.
06:47
Stars will create the Goldilocks conditions for crossing two new thresholds. When very large stars die, they create temperatures so high that protons begin to fuse in all sorts of exotic combinations, to form all the elements of the periodic table. If, like me, you're wearing a gold ring, it was forged in a supernova explosion. So now the universe is chemically more complex. And in a chemically more complex universe, it's possible to make more things. And what starts happening is that, around young suns,young stars, all these elements combine, they swirl around, the energy of the star stirs them around, they form particles, they form snowflakes, they form little dust motes, they form rocks, they form asteroids, and eventually, they form planets and moons. And that is how our solar system was formed, four and a half billion years ago. Rocky planets like our Earth are significantly more complex than stars because they contain a much greater diversity of materials. So we've crossed a fourth threshold of complexity.
07:57
Now, the going gets tougher. The next stage introduces entities that are significantly more fragile, significantly more vulnerable,but they're also much more creative and much more capable of generating further complexity. I'm talking, of course, about living organisms. Living organisms are created by chemistry. We are huge packages of chemicals. So, chemistry is dominated by the electromagnetic force. That operates over smaller scales than gravity, which explains why you and I are smaller than stars or planets. Now, what are the ideal conditions for chemistry? What are the Goldilocks conditions? Well, first, you need energy, but not too much. In the center of a star, there's so much energy that any atoms that combine will just get busted apart again. But not too little. In intergalactic space, there's so little energy that atoms can't combine. What you want is just the right amount, and planets, it turns out, are just right, because they're close to stars, but not too close.
09:00
You also need a great diversity of chemical elements, and you need liquids, such as water. Why? Well, in gases, atoms move past each other so fast that they can't hitch up. In solids, atoms are stuck together, they can't move. In liquids, they can cruise and cuddle and link up to form molecules. Now, where do you find such Goldilocks conditions? Well, planets are great, and our early Earth was almost perfect. It was just the right distance from its star to contain huge oceans of liquid water. And deep beneath those oceans, at cracks in the Earth's crust, you've got heat seeping up from inside the Earth, and you've got a great diversity of elements. So at those deep oceanic vents, fantastic chemistry began to happen, and atoms combined in all sorts of exotic combinations.
09:57
But of course, life is more than just exotic chemistry. How do you stabilize those huge molecules that seem to be viable? Well, it's here that life introduces an entirely new trick. You don't stabilize the individual; you stabilize the template, the thing that carries information, and you allow the template to copy itself. And DNA, of course, is the beautiful molecule that contains that information. You'll be familiar with the double helix of DNA. Each rung contains information. So, DNA contains information about how to make living organisms. And DNA also copies itself. So, it copies itself and scatters the templates through the ocean. So the information spreads. Notice that information has become part of our story. The real beauty of DNA though is in its imperfections. As it copies itself, once in every billion rungs, there tends to be an error. And what that means is that DNA is, in effect, learning. It's accumulating new ways of making living organisms because some of those errors work. So DNA's learning and it's building greater diversity and greater complexity. And we can see this happening over the last four billion years.
11:15
For most of that time of life on Earth, living organisms have been relatively simple -- single cells. But they had great diversity, and, inside, great complexity. Then from about 600 to 800 million years ago, multi-celled organisms appear. You get fungi, you get fish, you get plants, you get amphibia, you get reptiles, and then, of course, you get the dinosaurs. And occasionally, there are disasters. Sixty-five million years ago, an asteroid landed on Earth near the Yucatan Peninsula, creating conditions equivalent to those of a nuclear war, and the dinosaurs were wiped out. Terrible news for the dinosaurs, but great news for our mammalian ancestors, who flourished in the niches left empty by the dinosaurs. And we human beings are part of that creative evolutionary pulse that began 65 million years ago with the landing of an asteroid.
12:18
Humans appeared about 200,000 years ago. And I believe we count as a threshold in this great story. Let me explain why.We've seen that DNA learns in a sense, it accumulates information. But it is so slow. DNA accumulates information through random errors, some of which just happen to work. But DNA had actually generated a faster way of learning: it had produced organisms with brains, and those organisms can learn in real time. They accumulate information, they learn. The sad thing is, when they die, the information dies with them. Now what makes humans different is human language. We are blessed with a language, a system of communication, so powerful and so precise that we can share what we've learned with such precisionthat it can accumulate in the collective memory. And that means it can outlast the individuals who learned that information, and it can accumulate from generation to generation. And that's why, as a species, we're so creative and so powerful, and that's why we have a history. We seem to be the only species in four billion years to have this gift.
13:32
I call this ability collective learning. It's what makes us different. We can see it at work in the earliest stages of human history.We evolved as a species in the savanna lands of Africa, but then you see humans migrating into new environments, into desert lands, into jungles, into the Ice Age tundra of Siberia -- tough, tough environment -- into the Americas, into Australasia. Each migration involved learning -- learning new ways of exploiting the environment, new ways of dealing with their surroundings.
14:04
Then 10,000 years ago, exploiting a sudden change in global climate with the end of the last ice age, humans learned to farm.Farming was an energy bonanza. And exploiting that energy, human populations multiplied. Human societies got larger, denser, more interconnected. And then from about 500 years ago, humans began to link up globally through shipping, through trains,through telegraph, through the Internet, until now we seem to form a single global brain of almost seven billion individuals. And that brain is learning at warp speed. And in the last 200 years, something else has happened. We've stumbled on another energy bonanza in fossil fuels. So fossil fuels and collective learning together explain the staggering complexity we see around us.
15:01
So -- Here we are, back at the convention center. We've been on a journey, a return journey, of 13.7 billion years. I hope you agree this is a powerful story. And it's a story in which humans play an astonishing and creative role. But it also contains warnings. Collective learning is a very, very powerful force, and it's not clear that we humans are in charge of it. I remember very vividly as a child growing up in England, living through the Cuban Missile Crisis. For a few days, the entire biosphereseemed to be on the verge of destruction. And the same weapons are still here, and they are still armed. If we avoid that trap, others are waiting for us. We're burning fossil fuels at such a rate that we seem to be undermining the Goldilocks conditionsthat made it possible for human civilizations to flourish over the last 10,000 years. So what big history can do is show us the nature of our complexity and fragility and the dangers that face us, but it can also show us our power with collective learning.
16:17
And now, finally -- this is what I want. I want my grandson, Daniel, and his friends and his generation, throughout the world, to know the story of big history, and to know it so well that they understand both the challenges that face us and the opportunities that face us. And that's why a group of us are building a free, online syllabus in big history for high-school students throughout the world. We believe that big history will be a vital intellectual tool for them, as Daniel and his generationface the huge challenges and also the huge opportunities ahead of them at this threshold moment in the history of our beautiful planet.
17:11
I thank you for your attention.
17:13
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