The Deadliest Disease in Human History

Over my nearly five years of hosting this show, one of the guests I’ve felt the most kinship with is the author John Green. We both know something about being thrust into the spotlight without ever having ambitions to be there. Green built his reputation writing blockbuster young adult novels like The Fault in Our Stars and creating extremely popular YouTube channels including Crash Course. I invited John back on the show to talk about his latest work, through which I think he’s found his life’s calling.

GREEN: We’ve reduced the burden of tuberculosis by 99 percent in the United States, in Australia and Germany and Japan, all over the world. We let this cure be where the disease is not, and we let the disease be where the cure is not. I find that reprehensible.

Welcome to People I (Mostly) Admire, with Steve Levitt.

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I first had John Green as a guest on this podcast in 2022. One of the things we talked about was quitting, which is something I talk about a lot. In the past, John said that discussion influenced his decision to stop writing the novel he was working on and instead devote himself to writing his new book, Everything Is Tuberculosis. I started our chat today by telling him how flattered I was by his comments, but suggesting that he should admit that I actually had nothing to do with his decision to write his new book.

GREEN: I am generally in the business of buttering up interviewers, but I genuinely mean that our discussion about quitting and the importance of quitting really did reshape my understanding of the novel that I was working on, which I can go back to any time, but it made me want to push TB to the fore, and that’s what I’ve done over the last couple years.

LEVITT: So when I first heard you were writing a book about tuberculosis, I thought to myself, why would John Green write a book about a disease that barely even exists anymore?

GREEN: I felt the same way when I started learning about tuberculosis. I was in a tuberculosis hospital in Sierra Leone in 2019 when I first became aware of this crisis, and they were like, we’re going to go to a TB hospital today. And I was like, “Is that still a thing?” And it turns out it is very much still a thing.

LEVITT: Yeah, so what are the numbers? The numbers are mind blowing.

GREEN: They are, they’re truly mind boggling. So about 10 million people will get sick with tuberculosis this year, and about 1.25 million will die. And unfortunately, unlike a lot of the healthcare problems that we face together, this one is probably going to be getting much worse over the next few years. And so those numbers will go up.

LEVITT: And just to put 1.25 million into perspective, how does that compare to the other infectious diseases we talk about? So there’s Covid, malaria—

GREEN: I think we’ve done a bad job of counting Covid deaths and so it’s a little hard to nail that one down. But we have a pretty good sense of how many people die of H.I.V. and malaria and typhoid And Ebola. And tuberculosis kills about as many people as H.I.V. and malaria and typhoid and Ebola combined.

LEVITT: In the U.S., I think last year maybe what 500 people died of tuberculosis. So it’s just completely invisible to us. And we think about it being in the past because there was a time when in Northern Europe, what, it killed maybe 25 percent of all the people?

GREEN: Yeah, that’s right. So in the late 18th, early 19th century in Northern Europe and in parts of the United States, it was killing about one out of every four people, maybe even a little bit more than that. And historically, by some estimates it’s killed about one in seven, one in eight people who ever lived. So this is a huge part of our past. And you’re right, it’s not as much part of our present. We have about 10,000 cases of active tuberculosis every year in the United States, but because tuberculosis is curable, the vast majority of those people survive. It’s the rare issue that’s merely a resource problem. Now, I would argue it’s actually a little more complicated. Like anything, the more you zoom in, the more complicated it gets. But tuberculosis exists because we allow for it to exist. And to me, that makes it the exemplary disease of injustice.

LEVITT: So just to maybe set the stage for talking about the efforts that you and others are trying to do to fix this problem. Could you contrast the way we treat TB in the U.S. and the way we treat TB in Sierra Leone or India or some other place? Just so people understand what switch needs to be flipped.

GREEN: Sure. So when my friend Henry got tuberculosis in Sierra Leone, he was living with multi-drug resistant tuberculosis, he was told that unfortunately it didn’t make sense to offer him the newest and best treatments because it made more sense to focus on prevention and to focus on people who have cheaper forms of tuberculosis to cure.

LEVITT: So it’s cost benefit. This is a cost benefit analysis—

GREEN: Classic cost-benefit analysis.

LEVITT: And it makes sense, right? Because if you have a million dollars to spend, it does make sense to spend it most effectively. The treatment we give people in the U.S. is expensive relative to the basic care that we’re giving to folks in Sierra Leone. So the basic regime, the one-size-fits-all regime that they use in Sierra Leone, DOTS is what they call it. What does that cost per person per year?

GREEN: Oh, it’s very cheap. It’s a few hundred dollars.

LEVITT: So the situation is if you have a version of tuberculosis, which is treated by the regular old guard set of standard drugs, then things are pretty good under that basic regime of what’s mostly available in developing countries. And some people have a drug-resistant version of tuberculosis. If you live in the U.S. that’s not such a big problem because we have all sorts of fancy ways of figuring that out and then treating you for that.

GREEN: So if you get tuberculosis tomorrow in Sierra Leone, you’re very likely to not know whether or not you have drug-resistant tuberculosis. And so you’re very likely to be given these four drugs that we’ve been using since the 1960s. Basically, between 1945 and 1965, we developed all these different drug classes to treat tuberculosis. And those are still the drugs that we’re using as our first line of defense against the disease. Because between 1965 and 2012, we developed no new drugs to treat tuberculosis. For comparison, I know that you talked recently to my brother who had cancer a couple years ago. And, you know, if Hank had gotten the same kind of care in 2023 that you would’ve gotten for Hodgkin lymphoma in the mid-1950s, he probably would’ve died. But we’ve made a lot of investments into better cancer care. We haven’t made a lot of investments into better tuberculosis care.

LEVITT: One of the key problems we have is that it’s a little bit expensive to figure out whether your TB is drug resistant or not. And it’s been judged too expensive to actually do those tests in developing countries. So we never actually get to the point of trying to allocate the expensive drugs to people because we don’t even know what drugs are going to work. So we just try the cheap ones on ’em, and we hope for the best. And that’s the state of what happens, right?

GREEN: That is often what happens. And by expensive, when you talk about these tests being expensive, I mean they’re $15. So, are they expensive? I’ve, you know, rarely gone out to dinner for less in the last year. But they are expensive in the context of the Sierra Leonian healthcare system. And that’s just not enough to build a functioning healthcare system. And so, they run again and again up against this resource problem, right? Like you have to treat mental health, you have to treat malaria. You have to treat diarrheal illnesses. And so, the least expensive interventions become the ones that get leaned on the most. And that means prevention and control over care. And that’s a real tragedy for people like my friend Henry, but also for thousands of other people who get drug resistant tuberculosis. It means many of them will die. And until recently, it was the standard of care for them to die. As late as the early two thousands, the guidelines were for people with drug-resistant tuberculosis to just receive supportive care, which meant basically take care of them as they die.

LEVITT: So, I’d like to talk about the past, because here’s this disease — horrible disease, which is I assume, terrible to die from. As you suffocate your lungs stop working. And yet somehow or other it was romanticized, right? People like, Keats or Byron or whoever it was, that’s our image of tuberculosis. People with disease are usually treated like their monsters, lepers, the plague. Could you talk a little bit about how and why this disease was the one to get romanticized?

GREEN: Well, you’re right that disease is usually very stigmatizing, and I think that’s because the social order wants to make sense of illness by saying it doesn’t happen to people like us, which is of course ludicrous because that implies that there’s a certain category of people like us. It also implies that there’s a certain category of people who are invulnerable to disease, which we know is not true. But I think the social order’s desperate desire to create a kind of healthy core means that we push people to the side who are living with serious illness. And I saw this up close when my dad had cancer twice when I was a little kid. People would say that he got cancer because his parents smoked, but sometimes they would also say that he got cancer because he bottled up his emotions. This was a very common thing to believe in the ‘50s and ‘60s especially, but it continued. Like pushing down your emotions would lead to a literal metastasis. What a horrible thing to say to someone who’s in their mid-thirties and has two small children and is trying to live with a serious illness. But this is what we do with illness all the time. We take people and we double their burden that in addition to living with illness, they now have to also live with the way that we’re imagining this illness. With tuberculosis though, while it was always stigmatized, like Keats never used the actual word “consumption” in his letters, because he was terrified of using it. It was always stigmatized, but it also came to be deeply romanticized. As you mentioned, Lord Byron, like Byron said, he would like to die of consumption because the ladies would say how interesting he looks in dying.

LEVITT: Oh God.

GREEN: Charlotte Brontë said as her sister was dying of tuberculosis that she was aware that consumption was a flattering malady. It was seen as a disease that made you both beautiful and brilliant, a disease that gave you a kind of sensitivity to the suffering in the world, and also gave you this great creative power. And that all stemmed from two things. First we believe that tuberculosis was inherited, that it wasn’t infectious, but it was genetic. And so, it made a kind of sense in early 19th century Northern Europe, to imagine this as being inherited alongside other personality traits, like a depth of feeling or whatever. But then the second thing is that when we couldn’t stigmatize this disease away, and we couldn’t because wealthy people got it, healthy people got it. Charles Dickens called it, “The disease that wealth never warded off.” I think we began to romanticize it because we couldn’t stigmatize it away. We couldn’t say, “These people are less than human and so they deserve to be at the edge of the social order.” And so we started to say, “These people are more than human, but they also still belong at the edge of the social order.” Like romanticization is not a favor that we do to people. I know this from when I was a kid, right? And I would romanticize the young women in my life and I thought I was doing them a huge favor by seeing them as these goddesses that lived on pedestals. But of course, from their perspective, they just wanted to be people. And the romanticization of another person is no favor to them or to us.

LEVITT: I know that the artist Rubens used to draw really plump, full-figured people and that was a sign of beauty in the old days. It’s interesting to me that the wasting away waif-like look already was starting to become popular back in the 19th century.

GREEN: Yeah, and became popular largely because of this romanticization of tuberculosis because we began to see, especially for women, small bodies, weak bodies as beautiful bodies. And women would apply bella donna to their eyelids to try to get that wide-eyed consumptive look. They would apply rouge to their cheeks and red lipstick to their lips in order to look consumptive. Because people with consumption have very pale skin often. They get rosy cheeks and rosy lips from their fevers because the disease often is accompanied by fever. And this did become a very powerful sign of physical beauty, especially in women.

LEVITT: So then all of this romanticism got ruined when a German scientist named Robert Koch discovered that TB was actually caused by a bacterium. Do you know how we actually figured it out? Because it seems to me like a really difficult problem to pin down that a disease like TB is being caused by bacteria back in the 1880s.

GREEN: Yeah, it was really difficult to pin down. So people with tuberculosis have these clumps of white blood cells that have tried to surround the bacteria, and those clumps of white blood cells are called “tubercles,” which is why the disease is called tuberculosis now. They basically surround the bacteria and hold it in check rather than killing it because it has such a thick, fatty cell wall that it’s really hard to kill. And so instead they just surround it. And it becomes this sort of gross, tuber shaped — that’s why it’s called a tubercle. This tuber-shaped clump of white blood cells that has bacteria in it that can continue to stay alive and reproduce, but do so very slowly, basically. So Robert Koch pulls some material from inside one of these tubers and injects it into an animal. The animal becomes very sick indeed, and then he’s able to see on a slide that the same rod-shaped organisms that were inside the tubercle are now inside the animal. That doesn’t actually prove a chain of transmission necessarily. It just proves that these rod-shaped organisms are associated with tuberculosis. It could be something else in the tubercle. Who knows? What he does then is he takes some material from inside this sick animal and he puts it into a Petri dish. We didn’t have Petri dishes at the time, but he had this medium that he grew the bacteria in that mostly used egg, which we still use sometimes. And then once the bacteria had grown on this medium, this egg, he took the material from inside the egg medium, injected it into a healthy animal. And that animal also got sick. And that’s how he proved that there was a chain of transmission.

LEVITT: Now, usually in science, when people have big insights, it takes a long time before other scientists believe them. But I get the impression that this took over right away. People believed what he said and responded immediately to this insight, which is interesting.

GREEN: There was lots of debate about whether or not tuberculosis was infectious, even before Robert Koch. And certainly even after his paper, lots of people still argued that it was an inherited disease, but it was kind of a light bulb moment for the world health community because it was such an elegant proof. It was such a powerful display of microscopy. And so the vast majority of people were convinced by Koch. One of the people who was in the audience when Koch first revealed these results said, “I hold that day to be the most important of my scientific life.”

LEVITT: Koch pushed it too far though, right? I mean, you have so many interesting stories because as you say, “Everything is tuberculosis.” That’s the title of the book. But the story about Koch then thinking he had a cure — you couldn’t make up the story that you’re about to tell.

GREEN: No.

LEVITT: It’s so perfect. When you discovered it, you must have thought, ‘How did the universe deliver me such good material for a book?’

GREEN: I did. One of the joys of writing nonfiction as opposed to fiction is that you have to tell the truth, which is annoying of course, but then often the truth just astonishes you. And this is one such case. So Koch thought that he had a cure for tuberculosis. This material that we now call tuberculin. It was sometimes known as Koch serum, and he published the cure. And it was so exciting that there was a supplement of the British Medical Journal published just about this. And who should read it, but a country doctor sitting in southern England who was so moved by this description of a cure that Koch had published because Koch was so known for his meticulous research for being so careful for always being right. This young doctor was so moved that that day he closed his medical practice and went to Berlin. He knocked on Koch’s door. Koch wasn’t home, but he talked to the butler. And then he started going around trying to understand this thrilling, exciting cure. And it turned out that this young doctor from England was the first to establish that actually this cure was not a cure. It was likely making people sicker rather than healthier. But what it was, was a test. If you had an immune response to Koch serum, that meant that you had been exposed to tuberculosis and had some kind of tuberculosis infection. And the doctor from southern England who discovered this and who was the first to report on the fact that this cure was not a cure but could be used as a test, was none other than Sir Arthur Conan Doyle, the guy who wrote Sherlock Holmes.

LEVITT: Much later. Nobody knew who he was at the time, right?

GREEN: Yeah. He wasn’t at all famous. He barely was able to get a newspaper to sponsor his trip.

LEVITT: You gave a very abbreviated version of the story. You tell it in greater detail in the book, but it’s just so interesting how Koch wanted so badly for his serum to be a cure that even though he was a great scientist, he blinded himself to what in many ways now with Sir Arthur Conan Doyle’s work seems obvious. It’s true as an economist, someone who tries to produce ideas, the seductiveness of once you have something that’s pointing in a direction you so badly want it to happen — that that blinding — I wish I could identify more with Sir Arthur Conan Doyle, be the one who finds it, but I actually feel a lot more like Koch in that situation.

GREEN: It is funny you say that because I feel the same way about a lot of my work. It’s so powerful to think that you might be onto something big. And this is true not just in nonfiction, it’s also true when you’re writing a story like you think you’re onto something that’s so big, that’s so good. And then when it disappoints you, or when the sort of story evidence doesn’t point in that direction, it’s just devastating. I’ll give you an example of what I mean, and this is quite embarrassing, but when I was writing The Fault in Our Stars. It’s about a girl living with cancer and her favorite author lives in the Netherlands. I had this idea that her favorite author comes back from the Netherlands to visit with her, and then they get really interested in the trolley problem. That problem in philosophy where you can make an active choice that results in the death of fewer people, but you have to make an active choice that will result in the death of some people. And they get so obsessed with this that in this version of the story I wrote, they end up literally tying this girl to actual train tracks. Which is such a bad idea to end a novel! It’s such an embarrassingly terrible idea, but I was so compelled by it. I was like, “This is the solution. This is the way out.” And my editor, my poor editor, read it and she said, “It’s such a nice book and it’s so good until the last 30 pages, which are just insane.”

LEVITT: It’s great that your editor would say that. Because I do think if it had been in the book that followed The Fault in Our Stars, it would’ve been much harder for your editor to say that. You’re lucky to have an editor who’d tell you the truth.

GREEN: I am very lucky and I’ve had the same editor since my first novel, and I think that’s wise because she knew me when nobody was interested in reading my work. When I couldn’t pay anyone to get interested in reading it. So I trust her a lot, but she also has to trust me to be able to say, like, “I’m sorry, you’re a great guy and you’re a good writer but, boy, is that a bad idea.”

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LEVITT: So let’s go back to tuberculosis. So we realize now it’s caused by a bug and now the societal ramifications are enormous. I love, again, amazing examples — so fashion around facial hair flips. Flips on a dime.

GREEN: Yeah, we go from a world of beards to a world of clean shaves. It’s important to understand that people were really terrified once they realized that microbes were killing us, and that most of what killed us at the time was microbes. We were this animal that had conquered the lion and the tiger and the bear. And we were living in what we thought of as extremely civilized situations. And then it turns out that almost all of us are still being killed by animals, it’s just these animals are invisible and they’re crawling in and on us all the time. And so the beard became a big source of anxiety because it was feared what kind of untold monsters of invisibility might be lurking within these beards. And so that kind of ushered in an era of clean shaves. It also was part of the reason why hemlines rose, because people worried that women’s floor-length dresses might be dragging tuberculosis bugs and other bugs from the streets into the home and so on.

LEVITT: Now, I know from our past conversation that you’re very open about your own O.C.D. tendencies, and I think germs and infection are at the heart of it. What’s it like for you to think so much about these dreadful bacteria for two years? Did it not take a real psychological toll on you?

GREEN: Well, it did, is the short answer. It did take something of a toll on me. But I’m always thinking about them, regardless of whether or not I’m writing about them. It’s a source of contemplation for me. It’s very strange to me, to be honest, that most people aren’t freaked out by the fact that there are bugs crawling in and on them all the time. We think of ourselves as this single organism, but we’re not a single organism, we’re this massive collective that is strange to me. I’m sure on some level I was indulging my own fascination with microorganisms, but it proved to not be in an unhealthy way. I guess the answer to your question is that I could only have written this book if I was relatively well, if that makes sense. I work really hard to treat my chronic illness like a chronic illness. And so, yes, it continues to be an area of fascination for me. But I was well enough that I was able to encounter that stuff without being controlled by it.

LEVITT: Probably helps that we have really great cures for it. In the modern world it doesn’t in any way have to be fatal or even reducing life quality. Probably having that in the back of your head helps.

GREEN: Oh, for sure. For sure. Part of the horror of the contemporary story of tuberculosis is that I really don’t have to be worried about it. I know that if I were to get tuberculosis, first off, I would receive probably one month of preventative care that would result in me never getting active disease. But secondly, even if I did get active disease, it would be difficult, it would be challenging, it would be unpleasant, it would be all of that stuff. But I would survive and I would have no long-term effects.

LEVITT: So we’ve been talking about this tuberculosis project like it is just your latest book talking about statistics and interesting nuggets from Victorian England. But I get the sense that for you, this is so much more. The fight against tuberculosis and against the institutions that allow more than a million preventable deaths a year, it’s intensely personal — that you’ve internalized the despair and the desperation of the people who are affected by this illness; that you’ve been changed in some way, called to action. Does that feel right or am I getting carried away?

GREEN: No, that’s absolutely right. I think, to be honest, I needed a sense of orientation in my life for a long time. Now, there’s sort of two stories here. There’s the personal story of how I met a young boy in Sierra Leone named Henry, who shares the same name as my son, and who was living with multi-drug resistant tuberculosis. And our friendship is really the center of the book, and in some ways is the center of my own tuberculosis passion. Statistics are powerful, but you need human stories to connect with in order to really change your life. And part of the reason that I’m obsessed with tuberculosis is because of my friend Henry, and is because of what I watched him go through, so much of which was needless in order to survive multi-drug resistant tuberculosis. But I also think after The Fault in Our Stars and Turtles All the Way Down came out, my last two novels, something weird happens when you — I mean, look, this is the ultimate first-world problem, so I’m reluctant to even talk about it. But something weird happens when you achieve all of your dreams. Like when all of your goals for your career come true. And you may be able to relate to this actually, because you have this wild success that you never anticipated or even really desired. And then you’re asked, “What’s next?” And you have no good answer because the things that you wanted to have happen happened. That’s wonderful, but also there’s this almost lack of a sense of meaning in my life after that. And I did really struggle with that. Like, what am I going to do with this money, with this megaphone that I’ve been given, with all this attention that I have? Am I supposed to just seek more of it? Is the job to walk away from it all and pull a Salinger and live in the woods and write for myself? And for me, tuberculosis has given me a job.

LEVITT: It’s interesting, when we talked the first time, one part of the conversation I remember most vividly is that I asked you about your philanthropic efforts helping to create a hospital in Sierra Leone dedicated to improving maternal health outcomes. And you have donated many, many millions of your own dollars to that cause. Plus helped fundraise, I don’t know, at least $25 million at the time we talked, probably much more by now. It is a truly wonderful, selfless thing that you’ve done. But the thing that was interesting and that surprised me is I asked you, “Well why that cause?” I expected you to tell a story like you just told now about tuberculosis, about something personal, about this sense of tragedy. And your actual response, as I remember it was much more reserved and intellectually based. You talked about injustice and statistics and you said something to the effect of, well, I have a lot of trust in the people at Partners in Health and that they think this is a really good use of philanthropic dollars. I mean, I don’t know you, it was a one-minute part of our conversation, but I was surprised at the time that you had put so much effort into the hospital without it feeling like it was your calling.

GREEN: That’s really interesting. That hospital is going to open next year construction on it is almost completed. And I’m so proud of the role that I and our community have played in that even though the real center of the story is the Sierra Leonian Ministry of Health and the women and men who’ve built the hospital. But I think you’re right on some level. It felt like an important use of — it feels, present tense — like an important use of resources. I mean, the maternal mortality crisis in Sierra Leone is absolutely overwhelming as it is globally. And also maternal mortality is a bit of a Trojan horse. You can use maternal health as a strategy for building an overall healthcare system because really you can’t respond to maternal mortality unless you have stronger primary healthcare, unless you’ve got health workers out in communities identifying high-risk pregnancies. And while they’re there, they can also identify diabetes, and tuberculosis, and H.I.V. risk, and other things. So it strengthens the whole healthcare system in beautiful ways. But I think on some level you’re also probably right that it didn’t give me the same sense of orientation about my life. It felt like, well, this is a good use of resources. This is a good use of the money that I’ve made, and certainly there’s no reason for me to have that money. I can’t do anything particularly interesting or useful with it. And this is. And I do have a lot of trust in the folks at Partners in Health, and I do want to follow their lead. I never want to be the kind of philanthropist who thinks that because I made a bunch of money writing novels somehow now I’m an expert in the causes of suffering in the world. But I do think that I needed — in order to feel the same level of personal drive to fight diseases of injustice — I think I needed a deeper and more personal connection to that injustice, if that makes sense.

LEVITT: Yeah, makes complete sense. There also is a feeling I get as I read what you’re writing about tuberculosis. And it’s going to sound wrong because it’s not true, but I can see more of a vision to — I don’t want to call it a silver bullet because that’s not what it is. It’s not simple in any way, shape, or form. But on maternal health, look, it’s going to be a fight. It’s a slog. It’s really like person by person and you got to fix a bunch of things. But there’s almost an overriding sense on tuberculosis that there is a deep mistake being made in public policy. And if you could flip the switch on that mistake, you could have a scale of impact that is just monumental.

GREEN: That’s exactly right.

LEVITT: And I think it’s easier to find meaning in that kind of a fight then, a door-to-door fight, like one’s up against on maternal health.

GREEN: Yeah, I mean, I think both are important. The door-to-door fights are important, but you’re right that it’s very animating, and it makes me outraged, but it also makes me hopeful to know that there is a solution to this. This is a disease that’s been curable since the 1950s, and we know how to end it as a public health threat because we’ve reduced the burden of tuberculosis by 99 percent in the United States, in Australia and Germany and Japan, all over the world. We’ve shown an ability to do this, and so we know how to do it. And there’s something really outrageous to me that we let this cure be where the disease is not, and we let the disease be where the cure is not. I find that reprehensible. And you’re right, there is a way to flip a switch and make it go away. Now it would require a lot of resources, but we’ve done lots of things as a species that require a lot of resources.

LEVITT: Yeah, it would be many millions of dollars, but that’s not really a lot in the broader scheme of things.

GREEN: To an economist it’s not a lot. You’re so right.

LEVITT: So let’s talk about your efforts beyond the book to change policy around tuberculosis. You’ve got a really powerful and unique weapon at your disposal because through your incredible writing and the amazing content you’ve produced on YouTube over the years, you’ve developed an enormous and dedicated set of followers. They’re known as the Nerd Fighters, and you’re able to mobilize the nerd fighters at a moment’s notice with the aim of doing good. So you let loose the Nerd Fighters on Johnson & Johnson. Can you explain why?

GREEN: Well, Johnson & Johnson had the patent on this really powerful drug called bedaquiline that can treat multi-drug resistant tuberculosis. They had this patent for the 20 years that you get a patent for, and then they applied for secondary patents to evergreen that patent. And to do that they said, “Well, we’ve got this —” you can almost think of it as a pen with ink and a pen cap. And you can think of bedaquiline, the drug compound itself being the ink in the pen. But they said, “Well, we’ve got this special pen cap, and without this pen cap it doesn’t work as well. And so we’d like to patent the pen cap and then that’ll allow us to have another 10 or 15 years of control over the price of this drug.”

LEVITT: And just to be clear, this is what every pharma company does on every good drug they have.

GREEN: Absolutely. So in no way is Johnson & Johnson unique in this, and indeed I would argue that Johnson & Johnson emerges from this story looking in the end pretty generous, admittedly, after significant pressure. But you’re right. It’s important to understand that we’re talking about problems with systems, not problems with individual corporations, right? The system incentivizes companies like Johnson & Johnson to extend their patents for as long as possible so that they can make profit, which is their job. Their job is to return money to their shareholders, as much of it as possible. And so there is a problem with the needs of the market not aligning with the needs of human health, and that’s not a problem that’s exclusive to Johnson & Johnson.

LEVITT: So in 2023 you put up a YouTube video and what did you ask the listeners to do?

GREEN: I asked people to reach out to Johnson & Johnson and let them know that it’s unacceptable to try to extend the patent on a drug like bedaquiline, which was funded primarily with public money, primarily with U.S. government money. And what needed to happen instead was that Johnson & Johnson make their drug widely available for generic competition.

LEVITT: And then the next day they responded on Twitter — or X or whatever it’s called then, and they were totally dismissive.

GREEN: Yeah, they weren’t very nice. But I guess from their perspective, I wasn’t very nice either. So they probably would tell a different version of the story.

LEVITT: But if I’m understanding, it was the very next day, two days after you put out your call for people to heckle them, that they signed a contract saying they would let go of their patent. Is that right?

GREEN: That’s right. Now, they have said, and I believe, that this was already in negotiations before we got involved. But I do think we had something to do with the timing. And I think just as importantly, they initially were like, “Oh, we’re abandoning our attempts to file secondary patents in this country, in that country, but not in every country.” So countries like South Africa still were going to have to pay for the standard price of bedaquiline. But eventually because the pressure continued, they abandoned all of their secondary patents. And that means that bedaquiline is now available for 55-percent less than it was just a year ago.

LEVITT: The thing I find so striking about it — it obviously wasn’t just your letting loose the wolves because nobody could negotiate these kind of contracts in two days. But it’s a real success story. It points to a strategy for making things happen. You had a similar strategy with a company called Danaher, which I never heard of before, but I was surprised to find, has a market cap as we talk today of $145 billion. So this is this massive company. So can you talk about what the problem was around Danaher?

GREEN: Yeah, so Danaher makes this amazing test called GeneXpert. We talked around it already in this conversation. And that can identify whether somebody has tuberculosis and also whether they have certain kinds of drug-resistant tuberculosis in an hour or two. It’s an incredible test. Now, it’s not perfect. It’s got some problems, but it’s a great test.

LEVITT: It’s a little bit like the P.C.R. test that we use on Covid. It’s like a technological miracle that we’re able to identify these strains so quickly and so effectively.

GREEN: Exactly, it’s funny you should use that word because I remember being in Sierra Leone and talking to a lab tech about GeneXpert, and he said, “This machine is a miracle. I just wish we could afford the tests.” And the tests we know — or at least according to Doctors Without Borders’ reverse engineering cost analysis. We know that they were charging a markup of around double, or even a little more than the cost of making the test. And for their drug-resistant tuberculosis test, they were charging a markup closer to triple the cost of making the test. And I absolutely understand that companies need to make money, and I think that there’s plenty of opportunities for Danaher to make money in the United States on not just TB tests, but H.I.V. tests, flu tests, Covid tests, they make all kind of tests for GeneXpert. My issue is with charging the world’s poorest countries and those who serve them a huge markup when we know that that’s going to limit the number of people who can access the tests. And so we, again, asked Danaher to consider lowering the price of their tuberculosis tests. And after a lot of pressure, they did. They lowered them by 20 percent, which doesn’t sound like much, but as a result of that 20-percent drop, the Global Fund is able to purchase about millions more tests every year.

LEVITT: And then you also became a shareholder, right?

GREEN: Yeah, so I bought some Danaher stock just so that I can vote in their leadership votes. I don’t have quite enough to make my voice heard in a meaningful way, but I have enough to make my voice heard in a symbolic way. When you think about shareholder return, we have to think about that in the context of the fact that we live in a society. Like I am all for shareholder return. I understand that corporations need to make money. I don’t live in some fantasy land where there’s no profit incentive or no place for markets. I just think that at the same time, we have to make space for the reality that when the needs of the market don’t align with the needs of human health, we need to listen to the needs of human health or realign markets so that they do a better job of reflecting the needs of human health.

LEVITT: What I found so striking about the video you aimed at Danaher was, it is unlike any activism that I’ve ever seen before in the sense that you could not be more polite, and you could not be more flattering in saying what an amazing product this was. And then you also lay out very clearly the economics of what you’re talking about, which is, look, you understand that they want to make profits and because you care about global health, what your goal to do is to change their incentives by publicizing that their markups are causing many people to die. Saying, “Look, I’m just going to make this so costly to you that now you’re going to have a different path that’s going to serve you better.” It was really, I thought, a very powerful and thoughtful approach and really admirable in a lot of ways.

GREEN: Thank you. Well, that approach came from them actually. I spoke to one of their executives before we did this. I much prefer handling this stuff privately, if possible. So I spoke to somebody who is associated with the company and they said, “Doing that would cost us about $110 million.” And I said, “What I’m hearing is that you need me to cost you $110 million in bad publicity in order to make this change. And I will do that if I have to.”

LEVITT: I once talked to someone high up at Walmart, and there are a lot of people who don’t like Walmart for a variety of reasons. But one thing that Walmart does is when there is a disaster, a natural disaster, Walmart is really good and really quick at just delivering all sorts of stuff to the people in need. And, you know, I’m an economist and this was 10 or 15 years ago when I maybe didn’t think as sensibly and broadly as I should, I thought very much like an economist. I actually asked the person at Walmart, “Why do they do that? That seems like a really big cost.” And they said, “We give surveys to our workers, I think it’s once a month. And when we go and help people in need, the morale of our employees skyrockets. And so we think it is the single best investment we can make in our company is to make people proud to work there.” And I think you’re operating with Danaher on the exact same space. In the long run I think it might be very good for Danaher to actually follow your path because employees care.

GREEN: I think that’s so true. Employees care and other stakeholders care too. Nobody wants to make a world where human health is worse. The reason that those folks who work at Danaher worked so hard on developing the GeneXpert cartridge is precisely so that they could make the world better. And they have made the world better. Each of us as individuals is trying in whatever way we can to make the world suck less for each other. Filling gaps in the knowledge base, or uncovering important new science, giving us new tools to deal with the problems that we face together — we all want that. And yet, if the market is creating barriers to that then there’s something wrong — something’s gone wrong. And so I try to, in my little way, try to rectify that.

LEVITT: Now, I do think there’s one weakness in the strategy that you’ve taken with Johnson & Johnson.

GREEN: Oh, it’s so interesting because I also think there’s a weakness. I’m fascinated to know what your weakness is.

LEVITT: So, these firms have made big investments to try to develop these products. And if you are really successful, then ex-post after companies have made these breakthroughs that could save lots of lives in the developing world, and they’re not able to actually profit from them because of activism that doesn’t allow them to charge monopoly prices, then they will have less incentive going forward. You can imagine the higher ups at Danaher saying, “Look, this John Green guy’s a nightmare. Let’s just shut down all of our research on developing things for the developing world because we’ll never make any money, and he just tarnishes our reputation.” And in many ways, that has been one of the big problems in tuberculosis is, as you said, there was a 50-year period where there wasn’t a single new antibiotic introduced that was helpful. So if you’re too good at what you’re doing, it can actually have long-term detrimental effects.

GREEN: Yeah, so that is the exact weakness that I was going to cite. I’m glad that we’re on the same page about the weaknesses.

LEVITT: Okay, so I do have an answer!

GREEN: Okay, great. Because it’s something I worry about a lot and I don’t have an answer, so I can’t wait for your answer.

LEVITT: Okay, in the end, I don’t actually think this is a failure of firms or the market first and foremost. I think that this is really a failure of governments, of Western governments, and that’s who we should be blaming. Because there is an incredibly simple public policy intervention, which both gets the drugs to the people who need them at low cost and maintains and even increases the incentives of firms to develop new drugs. But the governments aren’t doing it. Okay. So the economics of what I’m going to describe is really simple, but let me go slowly to make sure that non-economists will understand.

GREEN: Oh, thank God. Otherwise, Steven, I’d be in big trouble.

LEVITT: Okay. So when you’re a company like Johnson & Johnson and you’re developing new drugs, you get a patent that lasts for a bunch of years, and while you have that patent, you have monopoly power. You’re the only one who’s allowed to sell that drug. And when you have monopoly power, that allows you to raise prices to generate extra profit. And what you do is you raise prices and you dramatically lower the amount that you sell, compared to what would happen in a competitive market. And that’s just the nature of Econ 101. So you might say, “Wait, why do we give patents to firms if it leads to these bad monopoly outcomes?” And the obvious answer is because we want to give firms incentives to innovate. But of course the downside is when the patent’s active, many people are dying because the prices are too high. So what’s the really simple public policy solution? Well, we grant the patent to Johnson & Johnson, and then, with great specificity, we can figure out how much monopoly profit Johnson & Johnson makes from their drug. And the U.S. government or European Union can simply buy from Johnson & Johnson, buy out their patent, say, “Look, we all know how much you’re going to make. We’ll give you this money as a lump sum, and then let’s put the drug into the public domain and allow everyone to make it.” And it’s absolutely what we should do because it gets the ex-anti incentives perfectly aligned for companies like J & J to go out and make great drugs. And it gets the ex-post incentives, once you’ve created this great drug, it gets it aligned so that we do the most good possible. And the fact that governments aren’t doing that, it isn’t because governments don’t understand that’s a possibility. I think it’s just either governments are completely and totally incompetent, or they just don’t care about saving people from TB. It’s one or the other. I would love to work with you to mobilize the Nerd Fighters to pressure governments to do these exact kind of buyouts, because I do think it’s the single best policy weapon we have.

GREEN: I think that’s a great idea, and I’d never thought of it before. And I like it a lot because it also means that we don’t have to wait X number of years between the discovery of an intervention and the rollout of that intervention to the world’s poorest communities.

LEVITT: Yeah, absolutely. And actually, we did it with the Covid vaccines, but we did it in reverse, right? Remember we signed contracts ahead of time, an advance market commitment is what it’s called. And my colleague Michael Kremer has been at the forefront of developing these ideas. So, we, the U.S. government, paid enormous amounts of money upfront to pharma companies in return for being able to buy their drug once it was developed. It’s true that these ideas are out there, but they’re not talked about very much. But they should be. And I would say your TB application is maybe the single best application I’ve ever run into for it. Because you can so clearly see the costs and benefits and it’s just so obvious what the gains are to doing it.

GREEN: Right. Yeah, I think the challenge right now is that we’ve got an administration and congress that’s really walking away from a lot of their long-term commitments and feels very far away from that being possible.

LEVITT: Yeah. I don’t think the U.S. government would be the place to do this now, but I do think that the European Union understands their increasingly important role in world health and stability. It is a really good moment to approach the European countries to bring this to them. It would be different if we were talking about a trillion dollars, right? But we’re not talking about that much money. And it’s so tangible. For the European governments I think there are incredibly positive benefits to being in this world leadership right now.

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John Green’s work on tuberculosis exists in two very different forms. One version is a New York Times bestselling book, which costs $28 in a bookstore. He’s also got a beautifully produced, completely free, hour-long tuberculosis video on his YouTube Crash Course channel, which is essentially a condensed version of the book. He released a YouTube video well in advance of the book, and that video now has over two million views. I asked John about the strategy of giving away video access for free before the book got published.

GREEN: Well, I guess this is a way to get people excited about the book. This is a way to whet the appetite for the book.

LEVITT: I am shocked that your publisher let you post the YouTube version and give it away for free. What was the conversation like where you told them you were planning on doing that?

GREEN: I don’t think I told them.

LEVITT: Interesting. Because I would suspect that in future book contexts there will be a clause which says you are not allowed to talk about what you’re doing.

GREEN: I did something similar — my previous book, The Anthropocene Reviewed, almost all of that was available for free in podcast form, or you could read it as a book and yet 650,000 people read the book. And so I think that there is something different about the act of reading or the act of holding a book that has some value. But I would be curious to know how The Anthropocene Reviewed would’ve sold in a world where I didn’t make it available as a podcast or how the tuberculosis book would be selling in a world where I didn’t make that Crash Course video.

LEVITT: You write books, you have incredible success and reach with YouTube. How do you think about those two media for communicating your ideas? Do you see strengths and weaknesses of the two?

GREEN: I do. I think the great strength of YouTube and social media is its immediacy. The sense that I can come up with an idea in the morning and have a response to it by the afternoon. That’s quite thrilling and was impossible to imagine when I was a kid. The problem is that everyone else can also do that. You’re in a very crowded space, but you’re also in a very loud space. A lot of times when people are watching my YouTube videos, they’re also doing something else. They’re playing Wordle. I had a meeting recently with a streaming service that will remain nameless, where they said, “We really need this to be second screen viewing.” Which meant that they needed the project to be something that you could watch while watching something else. So you’re on TikTok, but at the same time you’re watching something in the background and this would be the thing you’re watching in the background. And I was like, “I cannot imagine a less fulfilling creative project than being the thing that you also see while you’re watching TikTok.”

LEVITT: Oh, God. That’s great.

GREEN: A book, like you have to be so quiet when you’re reading a book, right? Physically quiet whether you’re listening to an audio book or reading a book with your eyes. It’s so intimate. It’s so long form. It takes a tremendous commitment of time and attention in order to read a book. But at the same time, I miss the immediacy of the internet when I’m writing a book. I miss the immediacy of feedback. And then when I’m making a YouTube video, I miss the kind of quiet contemplation that a book demands.

LEVITT: I think implicit in what you just said is that the economics of book writing for someone like you versus YouTubing, there’s really no comparison.

GREEN: Oh my God. Yeah.

LEVITT: I think you’re saying it’s the barriers to entry, right? Even though your YouTube videos are incredibly successful, in some sense, if you charged even a little bit for them, everything would change. The nature of the market in YouTube is that partly we have a hard time with micropayments — it’s very difficult for someone to pay you a penny or two pennies to watch a YouTube video. But even beyond that, there’s just this sense that there’s infinite content on YouTube so that leads the price to going to zero — not exactly zero because you get advertising revenue. It’s hard to be successful writing books. But for someone who is successful writing books, the economics are totally different.

GREEN: Yeah, no, you’re talking about $4 per book versus one-fortieth of one penny for a YouTube view. And so, even if people spend an hour watching your video there’s no comparison. There’s also no comparison in terms of the creative fulfillment for me, if that makes sense. Like it takes me so much longer to write a book even than it took me to write that hour-long YouTube video. It’s hard for me to imagine the amount of creative work that I would have to do to create a YouTube video that was as involved as writing a book is for me. It isn’t quite linear in terms of the amount of work. Making a five-hour or six-hour YouTube video wouldn’t be like making 60 10-minute YouTube videos, it would be like making 300 10-minute YouTube videos. Because that’s just the way the curve works. Like writing Everything is Tuberculosis took dozens of times, more hours than writing that crash course video did.

LEVITT: So, Henry, the young man who is so central to your interest in tuberculosis and plays such a big role in the book, isn’t in the YouTube video. It obviously was a very conscious decision. Can you describe that?

GREEN: Yeah. I didn’t put Henry in the YouTube video because I really saw Henry as the glue of the book and the organizing structure of the book. Whereas I saw the organizing structure of the video as a kind of linear history of tuberculosis. I did have some of Henry’s story in the first draft of the YouTube video, but especially as I began to tell the story of other survivors like Phumeza Tisile, who sued Johnson & Johnson to prevent the evergreening of that bedaquiline patent, I realized that those survivor stories were self-contained in a way that Henry’s story wasn’t. I also, when I made the video, frankly, didn’t totally know how Henry’s story was going to end. And look, obviously his story hasn’t ended. He’s a junior in college. That’s hardly the end of any of our stories, but I wanted to make sure that he was going to be okay.

LEVITT: What is your relationship with Henry like these days?

GREEN: Oh, it’s great. We talk almost every day. We talked earlier this morning about post-TB lung disease. We nerd out about that stuff. But also, I try to encourage him as he goes through school and everything. He just finished his final exams for the year, and now he’s a rising senior at the University of Sierra Leone. Yeah, we’re really good friends.

LEVITT: What’s it like for you having a character in one of your books not just live inside the book as it has been in your fiction books, but to actually be a living, breathing person who then goes on and exists beyond the book?

GREEN: Yeah, it’s weird. It’s really weird. And I really struggled with the question of how much of Henry’s story to tell, where to draw the line. Because Henry was so enthusiastic about me telling his story, and so ready for his story to be out there in the world. And so frustrated really, that he’d been denied access to the megaphone that I take for granted that it was more me pulling Henry back than the other way around. Because I know what it’s like to have a public life, and I know some of the drawbacks to it that maybe he hadn’t seen up close. At the same time, it’s very exciting because Henry is with us. Like Henry is here in the world and he gets to live his life and he gets to do stuff and he gets to fall in love and experience heartbreak. And I just am so grateful to his doctors, to the Ministry of Health in Sierra Leone, to Partners in Health for the fact that he can be here with us. Like it’s just — every life is a miracle, but with Henry’s life in particular, I’m conscious of the miracle.

LEVITT: You have really immersed yourself in tuberculosis, writing the book, publicizing the book, and all the other things you’ve been doing over the last couple years. And it’s obvious you’ll continue to do them, but I imagine at a much less intense pace than you have before. And my own experience with big projects like this where you really immerse yourself in them is when you finish them — not to imply that you’re finished, but you’re transitioning in a way on tuberculosis, that what’s left is an emptiness for me that’s really uncomfortable. This not having a sense of purpose is an awful feeling. Are you worried about that?

GREEN: Well, there’s a huge come down anytime I finish a creative project. I’ve been doing interviews and been on the road almost constantly. And I was talking to my dad and my dad was like, “Well, you know, you’re going to have a huge crash.” And I said, “Dad, maybe if I just stay on the road forever, I’ll never crash.” And he looked at me as a father only can, and said, “That’s not how it works, buddy.” The good thing, for me, this isn’t you write a book about bats because you’re really interested in bats and then you finish the book about bats and you’re like, “I think I’ll write a book about raccoons now.” For me, I think I’ve found my thing. I think I’ve found the thing that’s going to animate much of the rest of my life. And not just tuberculosis obviously, but the fight for health equity, the fight for more access to healthcare, broader access to healthcare, better systems that include more people, all that stuff. I will have a big come down at some point I will have a crash. And in the past those crashes have actually been pretty severe. So after the Fault in Our Stars came out, I got meningitis. Which sucked. After Turtles All the Way Down came out, I got this weird disease in my inner ear called Labyrinthitis, which was absolutely horrible, where I couldn’t open my eyes for two weeks and had to be in bed all the time. So I’m hoping to avoid any major itises. That’s the main thing is that I’d like to go itis free for the next few months. But you don’t know. This stuff does take it out of you. I obviously have to live within the limits of my body, this bacterial colony that I call a self. But at the same time, I want to push as hard as I can for as long as I can to spread the gospel that this is a disease that can be cured and that we don’t need to live in a world with it.

If you’d like to dive more deeply into John Green’s fascinating work on tuberculosis, the book is called Everything is Tuberculosis: The History and Persistence of Our Deadliest Infection. We’ve also provided a link in the show notes to his tuberculosis lecture on the Crash Course YouTube channel. And if you want to get involved in the fight against tuberculosis, check out the website tbfighters.org.

LEVITT: So this is a point in the show where I welcome on my producer Morgan to take a listener question.

LEVEY: Hi Steve, a listener named Ness sent us an email. In our episode with Raj Shaw, who is the president of the Rockefeller Foundation, you tell a story about how you asked Bill Gates once, why the C.E.O. of Microsoft gets paid so much more than the C.E.O. of the Gates Foundation. And you’ve talked about this before on the show. You think C.E.O.s of nonprofits should get paid comparable to C.E.O.s of for-profit organizations, essentially to attract top talent to nonprofits. Ness believes a reason that C.E.O.s of for-profits get paid so much is because they’re likely to do what a board of directors wants them to do, not necessarily that they have talent. Do you agree with this?

LEVITT: No, not really. And here’s why: The C.E.O. job is a job that a lot of people want to have. And so in settings where there’s a lot of competition, think about the N.B.A. or professional golf or teaching at a top university. When so many people want that job, you have to do something really special to make it to the top. And so I think there’s every reason to think that C.E.O.s on average are really talented people.

LEVEY: So, how do we know though that C.E.O.s of nonprofits are underpaid instead of C.E.O.s of for-profit companies are just overpaid?

LEVITT: Okay, so let’s be clear. I do think that C.E.O.s of for-profit companies are overpaid quite likely. And actually some of the most interesting evidence on that comes from Sendhil Mullainathan, who we’ve had on the show before, and one of his co-authors, one of my colleagues at the U of C Marianne Bertrand. And what they did is they looked at oil company C.E.O.s, this must be 20 years ago when they wrote this paper. So they looked at oil company C.E.O.s and they looked at their bonuses, and in principle, you arrange the contract of C.E.O.s so that if they do a really good job, they get a big bonus. And if they do a bad job, they get a small bonus. But what Sendhil and Marianne saw was that the bonuses of oil company executives were highly correlated with the price of oil. The C.E.O. of a particular oil company has absolutely no influence over the price of oil. But of course, the higher the price of oil, the more money that oil companies made. They shouldn’t be rewarded for that. So, in essence, we write these contracts that have a pretty high fixed payment to C.E.O.s, and then a big upside when things go well. And so a bunch of what C.E.O.s get rewarded for is luck instead of skill. And I think that leads to them being overpaid. But what I think is fair to say is that in the current market, people who have a lot of talent and don’t have a really, really strong proclivity towards social good opt only to go to the private sector market because the wages are so high. So if you think that C.E.O.s have talent, and you think that talent would help a nonprofit do better, your only choice is to try to compete with the C.E.O. salaries that are in the for-profit sector. Ultimately, a non-profit, they face a simple question, do we want to compete with the for-profit market for a C.E.O.? I think they probably do. But I think the obstacle you face as a nonprofit is that the norms are such that everyone is afraid to do that because they think donors will be mad. The way we measure nonprofits is by the ratio of how much they spend on staff versus how much goes directly to the recipients that they’re trying to help. And I think that kind of accounting gets in the way of making smart economic decisions.

LEVEY: Right. So the second point that Ness makes is that nonprofits shouldn’t pay their C.E.O.s more because it leaves less money for doing the important work that they’re doing. Which you’re saying is kind of a misconception.

LEVITT: I think that’s a really limited view. Solving the kinds of problems that nonprofits are trying to solve is really, really hard. I’ve tried to do it. And I’ve often failed, and you see how difficult implementation is. That takes real talent. If someone donates a million dollars, the impact that happens isn’t a million dollars minus how much goes to salaries at the nonprofit. The real impact is how really talented people can turn a million dollars worth of money into $5 million of impact, or $10 million of impact. And that’s what you hope talent can do is get more out of the same contribution. And so I think it’s really a limited view to suggest that every dollar that’s spent by a nonprofit on expenses is wasted. And you would never do that in a for-profit company, right? You would never say, “Look, the only thing we need to do is minimize costs. Even if that gets in the way of attracting the talent we need to really do our business right.” And it comes down to the way profits really are a very good bottom line measure that allow us to judge whether or not a company’s doing well, maybe whether the C.E.O. is doing well, and we don’t have the equivalent measures in most non-profit settings. And so we revert back to more primitive accounting type mechanisms which aren’t capturing the value of talent.

LEVEY: Ness, thank you so much for your question. Our episode with Raj Shah is called “Raj Shah Never Wastes a Crisis.” If you have a question for Steve Levitt, our email is PIMA@Freakonomics.com. That’s P-I-M-A@Freakonomics.com. We read every email that’s received, and we look forward to reading yours.

In two weeks, we’re back with a brand-new episode featuring Tom Holland, the host of the podcast The Rest is History.

HOLLAND:   I thought, well, it would be quite fun to write a novel in which Byron literally is a vampire.  And I kept coming across all kinds of stuff that really substantiated the case.

As always, thanks for listening and we’ll see you back soon.

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People I (Mostly) Admire is part of the Freakonomics Radio Network, which also includes Freakonomics Radio and The Economics of Everyday Things. All our shows are produced by Stitcher and Renbud Radio. This episode was produced by Morgan Levey, and mixed by Greg Rippin. We had research assistance from Daniel Moritz-Rabson. Our theme music was composed by Luis Guerra. We can be reached at pima@freakonomics.com, that’s P-I-M-A@freakonomics.com. Thanks for listening.

GREEN: This is my favorite podcast that I’ve ever done, so I assume that doing it a second time will be just as fun.

LEVITT: For me, our one and only conversation was one of the most interesting and fulfilling conversations of my whole life. And it made me really hesitant to have you on again because I’m afraid somehow the magic will be broken.

GREEN: Yeah, I’m worried about that too, especially if you liked me that much.