Hi, welcome back. Make yourself comfortable. In this presentation, I want to introduce you to the great divide between the traditional world and the modern world, because there are a lot of ways to define the traditional world and the modern world. Here is what I'm going to do. I think of the traditional world as a world in which the basic circumstances of life don't change much from one generation to the next. The modern world is one in which the conditions of life are changing constantly. One way of measuring that great divide is by looking at population, people's lives getting longer, women having more children. You can see some really pretty striking numbers. So if you look at this chart, you'll see that between the year zero in the common era, and the year 1,000, 1000 years, ten million people. Very little change. In the next 250 years, between the year 1000 and the year 1250, up 90 million. In the next 250 years, between 1250 and 1500, up 100 million. So very slight rate of population increase. Then this picks up a little bit between 1500 and 1750. It looks like in that 250 year period, 290 million people in 250 years. There have been some developments in irrigation capabilities and so on that have caused population growth in China, in India, in northwest Europe. But, keep those numbers in mind. 290 million, 250 years seems like about now, about a million people a year worth of population increase, and then contrast that to what follows. So remember that we said that between 1500 and 1750, 290 million in 250 years. Now look at this. That's 187 million people more. In how many years? 50 years. Think that's a fluke? Check this out. 1800 to 1850, that's 284 million: 50 years. In other words, the rate of population growth has more than tripled in the second half of the 1700s. And that just continues on into the 1800s, and if you follow this chart, we're off to the races. So something has happened. There's been a break point. At which the whole rate of human population on planet earth has dramatically changed in the late 1700s, a change then that doesn't quit. That's a great divide. Now here, with the aid of a wonderful interactive map prepared by the Public Broadcasting System for their Nova series. You can also see the distribution of population, as well as seeing how much it changes. Year zero, 1000 years later, very little change, you see where the distribution is. 800 years later, more change, up to a billion people. And you can see where most of the people live, concentrated here in Asia, here in Europe, some scatterings elsewhere. But then look at what happens after 1800. So you can see just a little more than 100 years later, now another billion people, and you can see some of the changes in the distribution of the population. There's a lot more people now in this place called North America. Even 33 years later now, yet another billion. And only 14 years later, the next billion. And another billion. And another. And by the year 2050, nine billion people. And you can see some of the distribution. So you can see then, as a historian, what an enormous swing is occurring beginning in the late 1700s. Now, let's look at another metric. Let's look at real income. [LAUGH]. It's really hard to calculate real income over different historical periods in different places. But a lot of economic historians, especially the late Angus Maddison, worked very hard at this and have come up with some roughly comparable numbers that allow us to get a sense of how real income has changed over time. Here's a wonderful chart from the economic historian, Gregory Clark, in his book published by Princeton University Press. Now the point of this chart is: even if population is increasing, if there's still only a finite amount of stuff that people are producing, more people have less stuff to go around, therefore the amount of food available to them drops if the population goes up. This is called the Malthusian trap. More people, less stuff to go around, population declines again, rises, declines. Real income stays pretty constant. Because there's just a finite amount of stuff to go around. That pattern with the Malthusian trap, named for the demographer Thomas Malthus, follows this pattern, you can see, for nearly 2,000 years of human history. Up to about 1800. And then you can see what happens after that. The Malthusian Trap broken. Another great divide. Another enormous change that's accelerating by the late 1700s, and then through the 1800s, is the rise of what I'm calling here ï¿½the global Europe.ï¿½ The spread of European based commerce, ideas, military intrusions to touch every important inhabited corner of the world. You can see the great divide, too, in the changing nature of political ideas. Up to about the middle 1700s, most of the world was governed by kings or emperors, princes, on the one hand, warrior chieftains; and then on the other hand, priests and traditional religions. The political revolutions, what we might think of in America as the American Revolution, the Declaration of Independence and all that. In Europe, they might think of the French Revolution. Liberty, equality, fraternity, those ideals and their spread. These are all developments that convulse the European world in the late 1700s, but then they become part of a global political vocabulary. Either people accepting it or rejecting it, but they're reacting to it. It's changing the conversation. Yet another break is cultural. In the traditional world, there seemed to be finite limits on everything: on how much food could be grown, on the availability of energy, limits on how much you can even understand the world around you. With all kinds of breakthroughs in science and the development of technology in the late 1700s and 1800s, the sense of human mastery over the environment, human ability to create new sources of energy, has enormous cultural effects. Just the whole beliefs people have, about their relation to the world, change. Their sense of not just limits, but also possibilities, the way in which they get to know or perceive other kinds of humans. The way they identify themselves. Who are we? To what community do we belong? How do we define our status? In what ways do we try to get income and assure our prosperity? How do we protect ourselves? All of these things are undergoing enormous change. We'll talk some more about those different belief systems next time, delving more into what we mean by the traditional and the modern. See you then.