Though the availability bias hides it from us, human progress is an empirical fact. When we look beyond the headlines to the trendlines, we find that humanity overall is healthier, richer, longer-lived, better fed, better educated, and safer from war, murder, and accidents than in centuries past.

Having documented these changes in two books, I’m often asked whether I “believe in progress.” The answer is no. Like the humorist Fran Lebowitz, I don’t believe in anything you have to believe in. Though many measures of human well-being, when plotted over time, show a gratifying increase (though not always or everywhere), it’s not because of some force or dialectic or evolutionary law that lifts us ever upward. On the contrary, nature has no regard for our well-being, and often, as with pandemics and natural disasters, it looks as if it’s trying to grind us down. “Progress” is shorthand for a set of pushbacks and victories wrung out of an unforgiving universe, and is a phenomenon that needs to be explained.

The explanation is rationality. When humans set themselves the goal of improving the welfare of their fellows (as opposed to other dubious pursuits like glory or redemption), and they apply their ingenuity in institutions that pool it with others’, they occasionally succeed. When they retain the successes and take note of the failures, the benefits can accumulate, and we call the big picture progress.

This is an excerpt from HumanProgress Board Member Steven Pinker’s new book. Buy a copy here.