Luke Muehlhauser is a researcher who studies risks to human civilization. Last year, he embarked on an amateur macrohistory project: collecting all the data we have available for six different metrics of human well-being, and graphing those metrics to get a picture of how the world has changed over time.

The six metrics he charted were life expectancy; GDP per capita; the percentage of the population living in extreme poverty; “war-making capacity,” a measure of technological advancement for which we have the most historical data; “energy capture,” which reflects access to food, livestock, firewood, and, in the modern day, electricity; and the percentage of people living in a democracy. Obviously, we don’t have a precise measure of many of these things for most of history — but we have enough to get a strong sense of some trends.

He plotted those measures across the entire sweep of human history. The resulting graph is startling:

The graph starts in 1000 BC and goes to the present day. It’s flat for most of human history. The Industrial Revolution is generally agreed to have begun in the late 1700s or first half of the 1800s, and that’s also when most of these markers of human well-being started to change.

Economic historian Joel Mokyr has called the 19th and 20th centuries “the most transformative centuries in all of human history.” From this chart, it’s easy to see why. Over almost all of human history, each of these metrics of well-being was completely flat. The same share of people lived in a democratic society — approximately none. Life expectancy at birth is believed by historians to have hovered in the range of 25 to 30 years (though this is mostly due to child deaths, not deaths in early adulthood). Almost the entire world lived in extreme poverty.

The most significant events of history had — when we zoom out and take a look at the big picture — only a small impact on overall well-being. The Black Death killed 10 percent of everyone alive and still barely moved these numbers. The fall of the Roman Empire did affect some measures of well-being, but on a scale that is barely visible on this graph.

In short, for most of history, all human events — the rise and fall of empires, the spread of plagues, the spread and schisms of religions, the invention of wheels and aqueducts and the printing press — barely affected the typical person’s life span, political freedom, economic productivity, or wealth.

And then, with the Industrial Revolution, all those things changed at once. Within 200 years, the human experience looked very different.

What made the Industrial Revolution different?

The Industrial Revolution refers to the transition, beginning in Britain and spreading around the world in the 19th century, to new — often factory-based — manufacturing processes. This transition affected almost every industry, from textiles and ironworking to transportation and agriculture. People were profoundly affected as well.

“Until about 1800,” Mokyr told the Washington Post, “the vast bulk of people on this planet were poor. And when I say poor, I mean they were on the brink of physical starvation for most of their lives. Life expectancy in 1750 was around 38 at most, and much lower in some places. The notion that today we would live for 80 years, and spend much of those in leisure, is totally unexpected. The lower middle class in Western and Asian industrialized societies today has a higher living standard than the pope and the emperors of a few centuries back, in every dimension.”

That sudden, drastic rise in standards of living is what the chart reflects.

Historians disagree on many details of this story — for example, on when the Industrial Revolution can be said to have begun, and on when it started producing real gains in standards of living for the average person. But historians broadly agree that extraordinary gains were associated with the Industrial Revolution.

The most striking lessons from this chart

I reached out to Muehlhauser to ask him about the biggest takeaways from this chart and from this view of human progress.

He emphasized how many metrics are missing from this picture, because we don’t have good data on them going back for centuries. He also emphasized that on its own, a chart doesn’t demonstrate causation — we’d need to look at the timing of industrialization by region, and the timing of changes in well-being, to draw any conclusions there.

Nonetheless, there are things we can learn just from this. We often think about history as a gradual arc of progress, with setbacks such as wars and famines and gains such as new ideas and technologies. Muehlhauser’s chart suggests a remarkable lack of correlation between those forms of progress and gains in human well-being.

While there was absolutely important technological and political progress occurring over centuries — new forms of government, new forms of warfare, new understandings of the world — global average well-being barely budged. The fluctuations associated with nearly all historical events are dwarfed by the changes associated with just one event: the Industrial Revolution.

One of the most striking things about the chart is how little most historical events affected it. The 1918 flu epidemic killed an estimated 20 million to 50 million people. It shows up on the chart, but as a brief blip in a general upward trajectory. World War II surpassed that death toll, killing more than 60 million people; it’s not even visible on the graph. Even though our capacity to slaughter each other has been growing — and the 20th century was rife with such atrocities — the overall trajectory has been that things keep getting better.

If you took a look at these numbers in 1800, you might have concluded that it’s impossible to really change anything about the human experience. Every change up to that point had not affected life span, not really affected political freedom, and not affected wealth or personal capacity to affect the world. It’d be easy to just conclude that the human condition was immutable.

That would have been a mistake, though. In ways that were hard to predict, things were about to change.

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