D.B.: I know that some people worry that acknowledging progress will make us complacent. Do you encounter this?

S.P.: Yes, and I respond that denying progress can make us fatalistic: If all our efforts at improving the human condition have failed, why throw good money after bad? More generally, people are so jaded by the narrative of decline that they can’t think coherently about progress; the concept just doesn’t compute. I’m regularly confronted with an example of something that has gone wrong, like the opioid epidemic or a rampage shooting, as a refutation of progress — as if progress meant that everything gets better for everyone everywhere always. That wouldn’t be progress; that would be magic. Progress consists of solving problems, and problems are inevitable. So of course things can get worse for some people sometimes. A more sensible way to think about progress is the framing by Barack Obama, presumably channeling John Rawls: If you had to choose a time to be born and you didn’t know who you’d be or where you’d be, what time would you choose? The answer is now.

D.B.: Of the advances you cite in the book, what three strike you as the most important?

S.P.: The components that go into the Human Development Index, namely being healthy, wealthy and wise. We live longer: Life expectancy at birth worldwide is now 71 years, and in the developed world, 80 years; through most of human existence it was around 30. Global extreme poverty has declined to 9.6 percent of the world population; 200 years ago, it was at 90 percent. In just the last 30 years, extreme poverty has declined by 75 percent — a stupendous achievement that is almost entirely unappreciated. Equally unappreciated is the fact that 90 percent of the world’s population under the age of 25 can read and write, including girls. In most of the history of Europe, no more than 15 percent could read and write, mostly men.

D.B.: Do you think a reluctance to point to progress inhibits our ability to achieve more progress?

S.P.: Yes, particularly among liberals, who in joining the chorus of decline have unilaterally disarmed in the fight for judicious regulation and social spending. Take pollution. Since the formation of the Environmental Protection Agency in 1970, air pollution (aside from carbon dioxide) has fallen by 60 percent, even as Americans have become more populous and richer and have driven more miles. But because many liberals today can’t bring themselves to acknowledge progress, they have cleared the field for opponents of regulation like Scott Pruitt to claim that the regulations have done no good and have only cramped our lives and dragged down the economy. Rather than saying “Environmental regulation has improved the environment while allowing the economy to grow,” they have said, ineffectually, “If you oppose regulation, you’re a bad person.”

The same is true with poverty. Ronald Reagan famously wisecracked, “Some years ago, the federal government declared war on poverty, and poverty won.” Few liberals would disagree. But Reagan was mistaken. If you factor in government social spending, such as the earned-income tax credit, rates of poverty have declined significantly. But here again liberals hand their opponents a weapon: the conclusion that all social programs are ineffective.

D.B.: Journalists typically write about sudden rather than gradual changes. But progress unfolds slowly. How could the news better reflect it?