It’s a “moral outrage,” Barack Obama told the United Nations delegates last week. He was speaking about the fact that 800 million men, women and children in the world scrape by on less than $1.25 a day and that billions of people are at risk of dying from preventable diseases.

So what moral failing is it that we should be outraged about? The president wasn’t clear. So let me make a nomination. I think believe we should be outraged when presidents, educators, newspaper columnists and others who would presume to tell us what to think lecture us about global poverty without bothering to learn the most basic facts economists have discovered on that subject.

Take a look at the chart below. It reflects the economics profession’s best estimate of how human beings lived—going back for one million years. As the chart shows, for almost all of human history, the average human being lived on the economic equivalent of a dollar a day. At times and places, a few lucky souls may have reached two dollars a day. And if they were really, really fortunate, they might have enjoyed a living standard equivalent to three dollars. But that’s it.