Bill Gates, the world’s richest man, and Warren Buffett, the third richest, are—not entirely coincidentally—two of the most unremittingly optimistic men on the planet. So when I met the two of them in New York recently to talk about the state of humankind, and about the future of American democracy, I had a clear understanding of my mission, which was to pressure-test their sanguinity at every turn.

I tried, and failed, though not completely. Both men appear to doubt some of President Trump’s innovations in rhetoric and policy. Both men have warm feelings about immigrants, and also about facts, and so are predisposed to react skeptically to recent developments in the capital. When I asked whether they believed America needed to be made great again, Buffett nearly jumped out of his chair: “We are great! We are great!” And when I asked about the Trump Administration’s problematic relationship with empiricism, Gates said, “I predict a comeback for the truth.” He went on to say, “To the degree that certain solutions are created not based on facts, I believe these won’t be as successful as those that are based on facts. Democracy is a self-correcting thing.”

On immigration, both men were emphatic: In explaining the success of the American experiment, Buffett said, “You had a welcoming attitude toward immigrants who then did wonders for this country.”

Despite their ephemeral worries, Buffett and Gates are both believers in the inexorable nature of progress, not only because they have been treated kindly by fate, and not only because they have concluded that America’s fortunes cannot be reversed during a single four-year presidential term, but because they have overseen a rather remarkable experiment in data-driven philanthropy. The work of the Bill and Melinda Gates Foundation, underwritten in part by Buffett’s support (in 2006 he pledged to donate $31 billion), has saved untold millions of lives. (The only person who could plausibly be credited with saving more lives in this period is President George W. Bush, who dramatically expanded the U.S. war on infectious disease during his two terms in office.) They have also overseen a remarkable experiment in peer-pressure-driven philanthropy: Their “giving pledge” encourages the world’s richest people to do as they have done, and commit much of their fortunes to good deeds. So far, they have gotten 157 pledges, which isn’t enough, but it’s something.

The impetus for this joint interview was the release of the annual letter issued by Bill and Melinda Gates on behalf of their foundation. The letter this year was addressed to Buffett, to whom Bill and Melinda Gates are profusely grateful. (Full, very MSMish-sounding disclosure: My wife works as an adviser on gender issues to Melinda Gates’s office, but she was not involved in the drafting of the letter.)

Once, a long time ago, Bill Gates was known principally as a brilliant, cold-eyed technologist and ruthless capitalist, but the work he and his wife have done to combat childhood mortality and infectious disease and promote vaccines and quality education has served to transform his public image. A Gates Foundation-supported effort has helped vaccinate 580 million children since 2000, and thanks in part to the work of the foundation, childhood mortality worldwide has dropped by half in less than 30 years. Polio, a core preoccupation of the foundation, has been very nearly nearly wiped out. Last year there were just 37 new cases worldwide, down from 350,000 when the campaign launched in 1988. The global public-health struggle against diarrheal diseases, which kill hundreds of thousands of children each year, has hugely benefited from Gates Foundation expertise and largesse.

The world, Bill and Melinda tell Buffett in their letter, is becoming a better place. This is an empirically true thing in many ways, and yet, for many people, in the U.S. and elsewhere, this period does not feel particularly hopeful. I asked Buffett and Gates why this might be so.

“I live in an upper-middle class neighborhood where the average income is $100,000, and every single person living there is living better than John D. Rockefeller lived, because of medicine, entertainment, you name it,” Buffett said. “My neighbors don’t have the power or prestige Rockefeller had, but if you have the choice of living the life that he could live and the life that they could now live, they’re all better off. In every respect, we’re living better than Rockefeller, a fellow who was alive in my lifetime.” He went on, “And you would think that people would be happy in this utopia, but they’re in a funk. They think their children are going to be worse off than they are. They’re absolutely wrong. ”

In our conversation below, you will find their analysis of the current, sour moment, and you will find—if this is a thing you need—some unalloyed good news. I’ve edited the transcript for concision and clarity.

Jeffrey Goldberg: We’ve had an economy that’s been in recovery for eight years, there are a lot of indicators suggesting that life is getting better, yet we’re in this fairly sour and fractured moment in the U.S., and, by the way, in Europe and elsewhere. Where’s the disconnect?

Warren Buffett:  I live in an upper-middle class neighborhood where the average income is $100,000, and every single person living there is living better than John D. Rockefeller lived, because of medicine, entertainment, you name it. My neighbors don’t have the power or prestige Rockefeller had, but if you have the choice of living the life that he could live and the life that they could now live, they’re all better off. In every respect, we’re living better than Rockefeller, a fellow who was alive in my lifetime.

And you would think that people would be happy in this utopia, but they’re in a funk. They think their children are going to be worse off than they are. They’re absolutely wrong. Their children are going to live better and their grandchildren are going to live even better. We’ve got half as many people in the world under five dying, and that number is going to get cut in half again, as Bill and Melinda show in their letter.

Goldberg: So what’s wrong with people? Why can’t they be happy?

Buffett: I think the disparity is what bothers people. It bothers me. Nobody can name the person who topped the Forbes list in 1982. It was Dan Ludwig. He had two billion dollars in 1982. It put him on top of the list. He’d barely make the cut today. The aggregate wealth on that list has gone from $93 billion to $2.4 trillion and the disparities are extraordinary.

There are two things you could have told my parents that they wouldn’t have believed back when I was born in 1930. One was that real GDP, capital, would go up six for one. In one person’s lifetime. The second thing is that, for a significant percentage of the people, not overwhelming, but a significant percentage, they wouldn’t be able to support a family with a couple of kids by working a 40-hour week. Both of these things happened.

With communication being so good now, people understandably feel that they haven’t participated in the growth. They’ve got iPads and smartphones that make their lives better, but because of these, they also see this incredible disparity.

Goldberg: Is this disparity reversible?

Buffett: People are correctly perceiving that a more and more specialized society will create wider disparities and results. Government has always interceded in some ways to change what a market system does—a market system is wonderful in producing what people want, but it also divides up the spoils. Absent government interference, an unfettered division of the spoils will produce greater disparities now than it would have a couple of hundred years ago.

Goldberg: Bill, you’re a technology optimist. But people have access on their phones to information that is false and that also highlights disparities.

Bill Gates: This all depends on how you use the phone. The real facts about child mortality going down are on the phone. is accessible on all of those phones. Visibility is generally your friend. Anyone can publish; you can see information and adapt.

On the actual improvements that we’ve seen, take my favorite book, The Better Angels of our Nature, by Steven Pinker, which talks about the decline in violence. The only thing that has declined faster than violence is people’s willingness to accept violence. So now, if you’re in a crowd and someone takes their kid and starts spanking them, people around them are like, “Oh my God, what are you doing? Should we call social services?” But in the 1950s, 90 percent of households said that teachers should spank kids in school who misbehave. So it’s changed a lot, and that disgust is a good thing.  

We’re not sitting here saying, “Hey, completely cheer up.” The fact is, the poverty rate is still significant. The dropout rate has come down a little bit, but it’s still significant. How could we take this dissatisfaction and tap into it in a constructive way?

Goldberg: Both of you come out of fact-based fields: Warren, you have to know accurately what’s happening in the markets, and Bill, you have to know if the software is actually working or not. But we’re in a discussion now in this country about whether we’re becoming a post-fact society. Does this pose an existential danger to progress?

Buffett: People learn from something. They get information some way. When I was a kid, it was basically newspapers. It wasn’t television, it was newspapers. The president would talk on the radio and we didn’t have anything else but a radio so people listened. Today information is coming at us from all angles, including from voices that, 50 years ago, they wouldn’t have been part of the scene.

Goldberg: So you’re worried about the future of truth.

Buffett: You always worry.

Gates: But I predict a comeback for the truth.

Goldberg: People in my business are certainly waiting.

Gates:  First of all, I think it’s overblown, this term “post-fact.” People want success, they want education that works, they want healthcare that works, and so to the degree that certain solutions are created not based on facts, I believe these won’t be as successful as those that are based on facts. Democracy is a self-correcting thing. And so, yes, I think facts will stay strong.

Buffett: I believe, and I think this has been borne out over 240 years, that this country gets better all the time.

Goldberg: Let me stay pessimistic here and ask, do you think democracy can survive social media, and the flattening out of information?

Buffett: Sure, sure.

Goldberg: Why are you two so optimistic about everything?

Buffett: [America] survived civil war, world wars, the atomic bomb, and the Great Depression. We survive. We’ve been gotten through a lot in this country. The truth is, we’ve got something that works, and the fact is it works and has kept working. It took us 150 years to get the 19th Amendment, but things gets better. We’re an aspirational country in a sense, and this country has a mechanism that allows aspirations to work their way into society, with a lot of fits and starts.

Goldberg: But you both know that empires rise and empires fall. There’s nothing that say that the exceptional qualities of the United States are immortal.

Buffett: I wouldn’t call it an empire. It’s a superpower. In 240 years it’s advanced not as an empire that has conquered other empires. It derives its greatness from within, from what it’s built, from the people who have come here.

Goldberg: So you’re not a big wall guy, I guess.

Buffett: (laughing) No! Just the opposite. Bill’s heard me say this before. We may be sitting here because two Jewish immigrants signed a letter to Roosevelt after fleeing Europe and coming to the United States. Einstein and Leo Szilard wrote the president and warned him that Nazi Germany was developing nuclear weapons. What immigrants have done for this country! Andy Grove, everyone. The quality of immigrants, the motivation of immigrants, this is what has contributed to the greatness of the country.

Goldberg: What would a warning sign of decline look like? When China develops Facebooks and Googles of its own?

Gates: It’s not a zero-sum game. If other countries come into the game and start solving diabetes, for instance—let’s say we do get rid of arthritis, diabetes,  depression—then people will be better off and they will see that science is moving at full speed. In any case, the U.S. is still in a dominant position in biology, in digital.

It’s amazing to see how strong the relative U.S. position is. Back in the ’90s, as CEO of Microsoft, every country I’d go to, they’d say, “What’s the secret sauce over there?”  I would say it’s universities, doing the infrastructure right, it’s the market mechanism, it’s risk-taking. It’s not about low taxes or anything. It’s an accumulation of hard workers from all over the world coming here and taking risks.

It’s fair to say people are wondering what the policies of this administration will be, but most of the strengths of the U.S. are really independent of the federal government—for example, the speed of scientific research. I just don’t see anything that could slow that down.

Buffett: To a better degree than most societies, we have unlocked human potential. We didn’t have a laboratory in which we selected out genes or anything like that, but we’ve come up with ways to unlock human potential. If the rest of the world does this, that will help us, and help them. It’s nothing like a zero-sum game.

The Chinese have taken part of our system and have adapted it to their own values and culture. Great. I want them to do terrifically. They’re not taking it away from us. They’ll come up with things that we’ll use just as we do things that they use.

Goldberg: Are you open to the idea that Trump might do something good?

Buffett: Any president comes in, there are all kinds of possibilities. We’ve been operating this way for a long time, and you’ve seen all kinds of zigs and zags, but we move forward.

Gates: Our foundation has worked with every administration. The last Republican administration put into the place the Pepfar program, one of the most generous new programs since the Marshall Plan. It has probably saved over 10 million lives, and it’s been maintained in a bipartisan way—Pepfar and the Global Fund together have saved millions of lives.

We’re not trying to say that there isn’t some uncertainty. It’s early enough to say that everything is open for discussion.

Buffett: Over time, it will average out. It may look like sausage-making in politics, but I do think people gravitate toward their better nature over time, with all kinds of zigs and zags, but I think the human potential that remains to be developed is huge compared to what we’ve seen so far.

Goldberg: Warren, do you see the entrepreneurial sphere producing other people like Bill Gates? And by that, I don’t mean people who invented smart things that made them rich, but people who pivoted in their lives to say that they’re going to spend their time reducing the disparities that separate humans?

Buffett: Absolutely, but Bill’s been a big factor in that. People follow examples.

Goldberg: What do you worry about the most?

Buffett: The thing I worry about is weapons of mass destruction.

Gates: Warren worries, appropriately, about nuclear weapons. He also worries about other ones. I worry more about bioterrorism.

Goldberg: So you’ve got the waterfront covered.

Gates: Well, we need someone to worry about chemical weapons.

Buffett: And cyber!

Gates: These are low-probability, high-impact things. If you say, what could drive us off the course, with the U.S. in the lead, that humanity is on, we would be more likely to say that it’s not politics, that it’s weapons of mass destruction, or an extreme natural disaster. Those are the things that, if we don’t solve them, that could knock us off course. Over time, if we don’t solve climate change, that starts.

Goldberg: But you’re climate-change optimists in the sense that you believe there are energy solutions to this problem.

Gates: If you told me that technology was frozen, that all we have is today’s technology, I would be very worried about climate change. But because of innovation, and research—I have this big breakthrough energy fund which is going to be a player in this—we have some really good inventions over the next 30 years or so.  I think it’s likely to happen. I do think we’ll avoid the biggest downsides of climate change.

Goldberg: Come back to the WMD problem—the increased velocity of life now, the flattening of hierarchies, the super-empowered terrorist phenomenon—these do not seem like hopeful trends when you’re worried about someone getting hold of a nuclear weapon, or bioweapons.

Buffett: The knowledge, and to some extent access to the materials, have increased exponentially since the pre-World War II era. That’s where government comes in, to work against this. We are dealing with individuals—probably not much chance for them—and organizations, who have a slightly better chance, and a few nations, which, under certain circumstances, would like to be able to kill millions of Americans.

Back in the Stone Age, if you were a psychotic, you’d throw a rock at the guy in the next cave. It stayed proportional—bows and arrows—up until 1945. Unfortunately, the ability to inflict mass damage, really mass damage, which is the only thing I see disrupting the progress of the world, is there. There are people who would do it if they didn’t currently lack materials.

Goldberg: Is the government ahead of the curve?

Gates: It could do more, certainly.

Buffett: It’s the number-one job.

Gates: In the nuclear space, in the biological space, we should do more. We can reduce the chance of something happening. We won’t drive it to zero. It’s hard to get people focused on this because during any four-year period the chance of this happening, thank God, is actually still quite low.

Goldberg: And how worried are you that we live in a uniquely fast age?

Buffett: No one knows the probability here. All I know is that in 1962 we were lucky to have Kennedy and Khrushchev in charge. If they were wired a little differently, if they listened to different advisers, if they were worried about political reactions to what course they might choose… The fate of the United States in a significant way depended upon two people who behaved pretty rationally.

Goldberg: Warren, let’s talk about philanthropy. What’s the best thing Bill has done with your money?

Buffett: Well, the best thing I’ve done is turn money that has little utility to me into money that has maximum utility for other people. Now I have the right people in charge, who are working full-time on this. They’re smart and getting things done.

This is the sense in which I run Berkshire. I delegate to an extreme degree when I find people who are good. Because they’re going to do a better job than I’m going to do sitting in Omaha reading a magazine. I also told Melinda and Bill when I set it up—and I told my children this as well—that I wanted them to fail a lot because if you’re not failing, you’re trying to do things that are too easy. Carnegie knew, when he gave those libraries, that it was a net plus. He didn’t have to worry about failure. There’s nothing wrong with that, but I want failure. I want to try difficult things. This is one of the reasons for private philanthropy—you can afford to fail.

Goldberg: Bill, what’s the biggest failure?

Gates: We’ve been trying to develop an HIV vaccine that we don’t yet have. We’re trying to get other tools, like a daily pill or a gel for women, and that’s taken a lot longer than we expected. This letter to Warren doesn’t focus on our education work. There, our goal of raising the math scores and literacy scores for the nation as a whole have not been achieved and I would say we’ll probably get the HIV vaccine before we see math scores go up a lot. The greatest successes are in public health, even though we have our difficulties. We are still optimistic in our education work. It turns out that it’s easier to catalyze in health. When we started, we thought that some health problems would be easy and some would be hard, our success on pneumonia and diarrhea has gone faster than we expected. Polio, with a little bit of luck, will be this incredible success story.

Goldberg: Warren, did you ever think you would know so much about diarrhea?

Buffett: Bill gets more excited about these things than I do, certain aspects of it at least.

Goldberg: At a public appearance at Columbia University several years ago, the theme of the event, you may recall was, “Keeping America Great.”

Buffett: We want a royalty.

Goldberg: There are a lot of lawyers between you and those royalties. So, does America need to be made great again?

Buffett: We are great! We are great!

Goldberg: Why do people think we need to be made great again?

Buffett: I don’t know. In 1776, there were four million people here, and 290 million in China. We have 75 million owner-occupied homes, 260 million vehicles, the greatest universities in the world, up and down the line—all of this from nothing 240 years ago. That’s pretty remarkable. There’s no one at the border saying you have to have a 140 I.Q. to get in, or a propensity to work 60 hours a week, but certain ingredients have created a miracle here. You had a welcoming attitude toward immigrants who then did wonders for this country.

Goldberg: But why do certain voters think we need to be made great again?

Gates: Politics goes back and forth. For instance, the fact that healthcare is so hard to get right, and expectations exceed what is being delivered—this causes frustration. The financial crisis, and how we should have reacted to that—I think a lot of people feel that we didn’t have a great resolution to that. Democracy is going to go back and forth on lots of and lots of issues. But things like scientific progress, or inventing new vaccines, or helping teachers be better—those things will be enduring assets, for the U.S. and for the world.

Look, I don’t have differential expertise in explaining political outcomes. Ask me about the immune system—

Buffett: Ask him about diarrhea! I can just see the headline now!