The big question for this segment is, what is this cause about and what will you get from it? [MUSIC] Welcome to this course on Big History analyzing complexity. We all know that our world is extraordinarily complex. And whether we are CEOs of an airline or we're trying to build a new anti-cancer drug or we're just juggling the household budget. We have to try to manage complexity. Just living is complex, but what is complexity, and can we get some grip on it? We all have an intuitive sense of complexities. Complex things have lots of moving parts, each of which seems to have it's own agenda. Yet they sort of fit together to form large evolving structures that have distinctive qualities of their own. We might be thinking of the global financial crisis or the world's climate system, or how a star works, or how the internet works, or how you work? Even an apparently simple organism such as an E.coli bacterium is horribly complex. It contains billions of molecules, each place with a exquisite precision in playing a precise role. So there are lots of moving parts and many complex feedback loops. Its metabolism for example, depends on delicate chemical pumps that drive protons one by one through its membranes to charge up its metabolic systems. It can even copy itself using the elaborate genetic machinery of it's DNA. And it can respond second by second to changes in it's environment. And that environment could be your stomach by the way, that's complexity. Like a modern city, gazillions of parts somehow fitting together to create something new whose behavior is difficult to predict. But can we understand complexity more rigorously? Is it a scientific concept that we can use to manage complex problems such as global warming? That's trickier, as yet we have no single rigorous definition of complexity. Instead of discipline seems to generate it's own definition, now the definitions don't all work together. Still, complexity seems to be a concept we can not live without. So we have to find ways of dealing with it. The Big History approach explored in the foundation course for the specialization, provides a wonderful way of getting a bearing zone complexity. Because Big History invites us to study complexity in all possible forms. From the complexity of the whole universe, to that of planetary systems, to that of living organisms of human history, and of today's staggeringly complex global world. Big History tells the story of a universe that began very simply. As a sort of thin mist of hydrogen and helium atoms all at more or less the same temperature. Even today in fact, most of the universe remains extremely simple. If I would hold you deep into space quite randomly, the odds are overwhelming that you would find yourself in a place that was very, very cold and extremely simple with virtually nothing around you, a near vacuum. And yet, in rare privilege environments such as the surface of planet Earth. Where the Goldilocks conditions were just right, more complex things appeared. This story really matters to us, because today's world, the world of the Anthropocene epoch represents a peak of complexity. In the Anthropocene, we humans have become so powerful that we suddenly find ourselves trying to manage an entire biosphere. It's climate systems, it's energy flows, it's plants and animals, and the fate of the 7 billion humans that now inhabit it. If we're to succeed in this project, we'll need to get a grip on extreme complexity. The Big History story allows us to study complexity from many different perspectives. Think of a crystal with many different facets, turn it slowly and you'll keep seeing the crystal in new ways. In this course, we'll turn crystal of complexity, looking at it from the point of view of a cosmologist or a biologist or a neurologist or an economist or a historian. What do they see? What can they learn from each other? And are they really looking at the same thing? Complexity seems to lie somewhere between total chaos and rigid order. If something consists of repeated patterns like a chessboard, then a mathematician can describe it very simply. It's not really that complex. On the other hand, describing a random arrangement of atoms is extremely difficult and the description maybe as complex as the thing being described. Does this mean randomness is complex? Surely not. The Nobel Prize winning physicist, Murray Gell-Mann is based at the Santa Fe Institute, which spends all its time studying complexity. He argues that you find complexity, and I'm quoting here, in a region intermediate between total order and complete disorder. All complex things have diverse components. They're assembled into patterns so that they work together to produce something that has new, emergent qualities. These are qualities that emerge, not from the individual components, but from the overall structure. The components of a water molecule are one oxygen atom, two atoms of hydrogen. But you'll look in vain for the quality of water in Earth's in either hydrogen or oxygen. It arises instead from a new relationship between the atoms. Your own cells arises in the same way, for the assembly and precise ways of billions of billions of components that are put in motion by complex flows of energy. Complex systems can be ornery, badly behaved. This is because they often consist of subsystems each of which may have its own subsystems all pulling in slightly different directions. Think about society with different classes that have different interests. These tensions create unpredictable feedback loops. Feedback loops may stabilize a system, like a thermostat on an air conditioner. Or they may exaggerate processes of change so that entire system suddenly change or move in new directions or breakdown that tipping points. Do we know enough to predict when these changes are coming? As you work through this course, you'll get used to turning the crystal of complexity and looking for new insights into the nature of complexity. And hints about how we might even begin to manage complexity on our astonishingly complex world. [MUSIC]
