For Novelist John Green, OCD Is Like An 'Invasive Weed' Inside His Mind

DAVID BIANCULLI, HOST:

This is FRESH AIR. I'm David Bianculli, editor of the website TV Worth Watching, sitting in for Terry Gross. Today's guest, writer John Green, mostly among teenagers who are fans of his young adult novels like. One of them, "The Fault In Our Stars," sold over 23 million copies, was on the best-seller list for 24 weeks and was adapted into a film. Green and his brother Hank also have a popular video blog called "Vlogbrothers." His young adult novels wrestle with the kind of issues you'd expect from someone like Green, who had considered joining the seminary and worked as a student chaplain at a children's hospital.

"The Fault In Our Stars" is about two teenagers with cancer who fall in love. His new novel, "Turtles All The Way Down," was published in 2017 but has just come out in paperback. It's about a 16-year-old named Aza still getting over the death of her father. She's also dealing with OCD - obsessive compulsive disorder - which leads to intrusive thoughts that get in the way of her day-to-day life.

Her thoughts also interfere with her relationship with her best friend and with her ability to have a boyfriend. Her obsession is with all the microorganisms that live on and in her body and her fear that she will become infected with a deadly bacteria. John Green drew on his own experiences with OCD, which he's dealt with since childhood.

Terry Gross spoke with John Green in 2017 when "Turtles All The Way Down" first was published.

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TERRY GROSS, HOST:

John Green, welcome to FRESH AIR. I'd like you to start by reading from your new book. But first, since her obsession is fear of getting C. difficile aka C. diff why don't you describe what this really horrendous disease is?

JOHN GREEN: Sure. C. diff is a disease that usually is associated with antibiotic use in hospitals. And it basically - there's this bacteria in your gut. And if it grows out of control, you can become very, very sick. And this is something that Aza worries about all the time. And she uses kind of compulsive behaviors, including checking the Internet to - for symptoms to try to manage this worry that she has.

GROSS: And just to get a little bit more graphic, I mean, C. diff leads to really extreme diarrhea. And in some people, particularly in elderly people, you can die if it's not treated. So it's a very serious and very problematic infection. And you're also going to refer in the reading I'm about to ask you to do to the microbiome, which is the collection of, you know, bacteria and microorganisms in the gut. And so the goal is to always have a healthy microbiome (laughter).

GREEN: Yeah. I mean, one of the really weird things about being a person is that about half of the cells inside of your body are not yours, they're microbes. And that's also something that is of some concern to Aza, and for that matter, to me.

GROSS: Oh, I know. It's a remarkable thing when you think about how your whole body, your skin, your gut, everything is just like populated with these microorganisms which is scientifically fascinating, but the more you think about it, the kind of creepier it is. And for her, it's more than creepy, it's disturbing. It's very deeply disturbing.

So I want you to do a reading. And this is from like a little more than midway through the book. And she has been friends with and is kind of starting to become girlfriend-boyfriend with a teenage boy. They're starting to kiss a little bit.

And because of this whole microbiome thing, it's making her really uncomfortable. And some of what we're going to be hearing is her intrusive OCD, her obsessive compulsive thoughts interfering with the rest of her thoughts. So some of what you're saying is written in italics. And all the italicized parts are those intrusive thoughts interfering in her mind. OK. Would you do the reading?

GREEN: (Reading) I told myself to be in this moment, to let myself feel his warmth on my skin. But now, his tongue was on my neck, wet and alive and microbial. And his hand was sneaking under my jacket, his cold fingers against my bare skin. It's fine. You're fine. Just kiss him. You need to check something. It's fine. Just be normal. Check to see if his microbes stay in you. Billions of people kiss and don't die. Just make sure his microbes aren't going to permanently colonize you. Come on. Please, stop this. He could have campylobacter. He could have nonsymptomatic E. coli that you could get. And then you'll need antibiotics. And then you'll get C-diff, and boom, dead in four days. Please, just stop. Just check. Make sure.

(Reading) I pulled away. You OK, he asked? I nodded. I just need a little air. I sat up, turned away from him, pulled out my phone and searched, do bacteria of people you kiss stay inside your body, and quickly scrolled through a couple pseudoscience results before getting to the one actual study done on the subject. "Around 80 million microbes are exchanged on average per kiss," endquote. After 6-month follow-up, human gut microbiomes appear to be modestly but consistently altered.

(Reading) His bacteria would be in me forever, 80 million of them breeding and growing and joining my bacteria and producing God knows what. I felt his hand on my shoulder. I spun around and squirmed away from him, my breath running away from me, dots in my vision. You're fine. He's not even the first boy you've kissed. Eighty-million organisms in you forever. Calm down. Permanently altering the microbiomes. This is not rational. You need to do something. Please. There is a fix. Please get to a bathroom.

(Reading) What's wrong, he asked. Nothing, I said. I just need to use the restroom. I pulled my phone back out to reread the study but resisted the urge, clicked it shut and slid it back into my pocket. But no, I had to check to see if it had said modestly altered or moderately altered. I pulled out my phone again and brought up the study - modestly. OK. Modestly is better than moderately. But consistently?

(Reading) I felt nauseated and disgusting but also pathetic. I knew how I looked to him. I knew that my crazy was no longer a quirk. Now it was an irritation, like it was to anyone who got close to me.

GROSS: Thank you for reading that. That's John Green reading from his new novel, which is called "Turtles All The Way Down." So of all the obsessive compulsive thoughts you could have given your main character, Aza, why did you give her this obsession with C. diff?

GREEN: Well, partly because I can relate to it. I mean, I needed a place where I could make a connection with Aza in order to write about her, I think. And I've long had a fear of contamination from microorganisms. That's long been one of the kind of focuses of my particular version of obsessive compulsive disorder. And so I think that was partly it.

But also, it's something that we live with all the time. It's something that surrounds us, you know. Like, in a way, bacteria are overwhelming us. We are the dominant species on the planet until and unless you start considering bacteria.

GROSS: So one of the things that she has are these thought spirals. I'm going to ask you to describe a thought spiral.

GREEN: Well, the thing about a spiral is that if you follow it inward, it just keeps going forever. It just gets tighter and tighter. And it never actually ends. And there really is no way for her to pull out of the thought spiral. And that's part of what makes it so frightening to her is that once she's in it, it doesn't feel like a thought spiral. It just feels like thought. It just feels like the way of the world.

It feels like she's not wrong when she's afraid of this infection or the other things that she fears. And that's really terrifying. It's also really isolating for her because she struggles to be able to describe it with language. She struggles for the words that would help other people understand what she's going through.

GROSS: She uses the word invasives (ph) to describe the kind of thoughts that you can't control and that take over. Is that your word, or did you get that from therapy?

GREEN: I think it's my word. When I was first told about OCD, I was told that these thoughts are called intrusives. But I actually heard the word invasives for some reason. And that is what it's like for me. It's like there's an invasive weed that just spreads out of control. You know, it starts out with one little thought and then slowly that becomes the only thought that you're able to have, the thought that you're constantly either forced to have or trying desperately to distract yourself from.

GROSS: So you've said that you have OCD. Tell us more about what form it has taken in your life.

GREEN: Well, I guess the sort of dominant form that it's taken in my life is that I get worried. I get afraid of having an illness or having some kind of contamination inside of my body, and then I become unable to stop thinking about that. And the worry begins to consume me. And, you know, in the face of that, you develop - or I have developed compulsive behaviors to try to manage that and deal with that. But for me, it starts - there's a reason the O comes first in OCD.

Like in the popular imagination, we always see people doing their compulsive behaviors because they're so visual, and they're so - often so strange and eccentric. But for me, it's the problem of my thoughts that is the problem. The compulsive behaviors are a way of trying to manage the kind of overwhelming fear that the obsessiveness causes me.

GROSS: So what are the things you're most afraid of contaminating you?

GREEN: I mean there's a - yeah, I'm being super intentional about not saying that (laughter).

GROSS: Oh, OK, OK.

GREEN: So yeah, that's the...

GROSS: That's fine. I don't want to...

GREEN: Yeah. That's the only thing that I can't. If I talk - I can't talk directly about it because I get squirmy.

GROSS: You get what, squirmy?

GREEN: Yeah.

GROSS: Would it be awkward, too, for us all to know? Like, say we met you in person sometime. Would it be awkward for you to have everybody know what that most vulnerable point was?

GREEN: Yes.

GROSS: Yeah, understandable...

GREEN: Yeah, that's why.

GROSS: Yeah, yeah, yeah. Let's take a short break here, and then we'll talk some more. If you're just joining us, my guest is John Green. He writes novels for young adults, and his most famous one is "The Fault In Our Stars," which was adapted into a movie. Now he has a novel called "Turtles All The Way Down." And I should mention, I think a lot of adults read your books, too. So we'll be back after a short break. This is FRESH AIR.

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GROSS: This is FRESH AIR, and if you're just joining us, my guest is John Green. He writes incredibly popular novels for young adults. His most famous one is "The Fault In Our Stars" about a teenage girl and her teenage boyfriend who both have cancer. And the new book is called "Turtles All The Way Down," and the main character in this is a teenage girl who has OCD. And so does the author, John Green.

So in the novel, there's a physical manifestation as well as obsessive-compulsive thoughts. The physical manifestation has to deal with digging the fingernail of one finger into the finger pad of another. Would you describe that physical manifestation of OCD?

GREEN: Yeah, so one of the way - she's been doing this since she was a little kid, and she just digs her thumbnail into her finger pad. Initially it was a way - she would ask her mom, why do I know that I'm real? How do I know that I'm really real? And her mom would say, well, if you pinch yourself, you know it's not a dream. And so it began as that. It began as a way of feeling real.

But over the years, it became kind of a locus of her obsession as well. And so this callus has developed on her finger pad. And now it's really easy for her to open up - to crack open that callus. And she gets worried that there's an infection underneath that callus. She covers it up with a Band-Aid because she's very embarrassed about it. But she often has to kind of open that up and try to drain the wound because she's worried that there's an infection there.

GROSS: Of course the more she does, the more she risks infection.

GREEN: Of course, yeah. I mean, this is not uncommon that - these are not rational behaviors. So, you know, I find that, like, trying to apply logic - at least in my own life, like, trying to apply logic to it is fairly ineffective.

GROSS: So have you had a physical manifestation like that, too?

GREEN: Yeah. Not exactly that, but I count on my fingers as a way of calming myself. And so I think that's probably why I started thinking about it, and then I liked the idea that, you know, it's literally affecting her fingerprint. You know, it's affecting who she is in a pretty profound way.

GROSS: The characters in your new book are also dealing with the deaths of parents. And in "The Fault In Our Stars," the two main characters are dealing with cancer that is likely to be terminal. So, you know, death plays, like, a major role in your books, and I'd be interested in hearing why.

GREEN: Well, I think it's a big problem. It's a big question.

GROSS: (Laughter) It's big - yes.

GREEN: And I think - and one of the things I like about teenagers is that they're looking - yeah, I mean, it's a big theme. But I think one of the...

GROSS: (Laughter) It's a - it's a problem.

GREEN: Right, yeah, I mean, I'm concerned about it. That's probably one of the reasons. But also, one of the things I like about teen characters is that they're grappling with the kind of questions around death and the problems that death creates for the first time sort of separate from their parents. And so they're asking, you know, is there an afterlife? And what are the implications for what we think about the afterlife?

And they're asking like, is meaning in human life changed by the fact of death? And I'm still really interested in those questions, and I like the way they approach them. Like, there's a lack of irony and a passion for those questions that I found really appealing when I was a teenager and that I still find really appealing.

GROSS: When was the first time you dealt with the death of somebody who you knew?

GREEN: When I was in high school, a classmate of mine died. And it was - we - I went to a very small school, and it was devastating to the whole school.

GROSS: How did the classmate die?

GREEN: She was in a car accident.

GROSS: What was your way of talking to your friends about it in order to get through it? Like, how did you - do you remember any of those conversations, the - in which you tried to talk through not only the loss that you were experiencing, but also, like, why do these things happen?

GREEN: Yeah, I mean, I think when you're in that position, those questions about meaning in life and what meaning you're going to find in life, they stop being rhetorical questions, and they become matters of life and death. They become the questions that you need answers to if you're going to figure out how to go on. And so we had a lot of those conversations.

You know, we had a lot of conversations where we were looking for meaning in life that could hold up against reality as we found it. And I've never found a lot of comfort in the straightforward answers to those questions, though, like everything happens for a reason or that sort of answer. And I think that did start in high school, and it did start with those conversations with my friends.

GROSS: Was there any kind of, like, religious service that provided answers that you either found comforting or, you know, just, like, bromides that were not helpful?

GREEN: There were a lot of bromides that weren't helpful. I mean, I'm Episcopalian, and I worked briefly as a student chaplain at a children's hospital. You know, I thought about going to divinity school. Religion has been part of my life for a long time. But at the same time, I don't find the answers to those questions in my religious tradition, to be honest with you - or, at least, not answers that satisfy me.

I don't find a satisfactory answer for, you know, the problem of the odyssey, as they call it in the world of religious studies - like, the problem of evil in the world. I don't have a good answer for why there is so much deep, profound injustice in the world and why, you know, the world behaves as if it were random. So if it isn't random, it's behaving as if it were.

GROSS: You know, as I mentioned, in your last two novels, teenagers are dealing with death - death of their parents or the possibility of their own death because they have cancer. So you spent some time working as - what? - an assistant chaplain at a children's hospital. Is that what you said?

GREEN: Yeah, a student chaplain, I think, is the technical term, but yeah, either way.

GROSS: So what were you exposed to there?

GREEN: You know, you're with people on the worst day of their lives. And people who work in children's hospitals for longer than the few months that I was there are real heroes to me because you see the worst things that can happen to people every day. And it's - it was really difficult for me. I was not you know, I couldn't do that work. I couldn't let it go. I still can't let it go 15 years later. And it was very hard...

GROSS: Were you mostly...

GREEN: ...To see that.

GROSS: Were you mostly talking with the parents or the children?

GREEN: Mostly with the parents, but I did hang out a lot with some teenagers who were sort of there long-term for various chronic health problems, mostly playing video games, to be honest (laughter). I was 22 at the time.

GROSS: That was probably really helpful.

GREEN: (Laughter) Yeah. And so if somebody had an Xbox, I would play video games with them.

GROSS: Did it feel awkward to be 22 and trying to help parents through a period when their child was, you know, dying or possibly dying? Did you feel like, who am I to help them? I'm 22.

GREEN: Yeah, of course, I did. Yeah. I felt unqualified in every possible way. But, you know, interestingly, I'm now 40, and I think I would still feel unqualified in every possible way. And, if anything, I might be worse at the job now. I think I was a pretty poor chaplain all those years ago, but I think I would be much worse at it now because now that I have - I just think that I would identify more. And it would be even more difficult for me to, you know, to be there for people in the way that they need when they're in that situation.

GROSS: Because you're a father now?

GREEN: Yeah.

GROSS: Are you surprised that so many teenagers want to read stories about teenagers who have the kind of problems that make you feel different from everyone else, like OCD, or like having lost a parent who died or like having cancer and maybe dying yourself? I mean, so many teenagers are just absorbed with, you know, school, finding a new boyfriend or girlfriend, just, like, having friends, figuring out how to make your way without being bullied or hated by other kids. (Laughter) But, I mean, you're dealing with really major problems in your book, not to make light of those other problems 'cause when you're a teenager, those other problems are really big.

GREEN: Right. No, I think that's actually the answer, though, is that when you're a teenager, no matter what your experience is, the problems are big and they're in many cases new. In many cases, it's the first time you've had this problem. So, you know, when I fell in love with my wife - you know, we have a great, awesome marriage, but I was also, like, this is, like, the other times I fell in love.

Like, I understood what was happening to me. When I fell in love for the first time, I was like, what is this completely unprecedented thing that has never existed in human history before? And so I think there's - you know, that intensity to the first-ness of all these experiences that teenagers are going through, I think, is part of what makes them connect to people who feel - who are going through really unusual experiences.

BIANCULLI: Author John Green speaking to Terry Gross in 2017. His latest young adult novel, "Turtles All The Way Down," has just come out in paperback. After a break, we'll continue their conversation. Also - algorithms. Our linguist Geoff Nunberg will explain how they determine what we see online and how often they get it wrong. And I'll review the new Showtime miniseries "The Loudest Voice" about TV executive Roger Ailes and his launch of the Fox News Channel. I'm David Bianculli, and this is FRESH AIR.

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BIANCULLI: This is FRESH AIR. I'm David Bianculli, in for Terry Gross, back with more of Terry's 2017 interview with John Green. He's famous for his young adult novels, including "The Fault In Our Stars," which was about two teenagers with cancer who fall in love. His latest novel, "Turtles All The Way Down," is now out in paperback. Green says he's drawn to writing young adult novels because his readers, like the characters in his stories, are experiencing so many things for the first time such as losing a loved one or falling in love.

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GROSS: Do you remember your first girlfriend, your first crush, and can you tell us about it? Or would you rather not?

GREEN: Yeah. Sure.

GROSS: (Laughter).

GREEN: I mean, my first crush was in third grade. And I wore, like, matching OP, like, shorts and a shirt to ask her to go with me, which was the parlance of the day. And I remember, like, you know, just feeling so incredibly nervous as if the stakes were actually high and I wasn't 9 years old and asking her to go with me. And she said, yes. And I was, like, this is, like, this is incredible. But then I had no idea, like, what the next step was. You know?

Like, I had no idea. Like, how do we proceed from here? So we eventually exchanged phone numbers and had a few phone conversations over the next few weeks, and then I don't think there was ever an official breakup. I think it just was sort of understood that this wasn't going to end in marriage.

GROSS: (Laughter). Did you tell your parents?

GREEN: Yeah. Yeah, I definitely told my parents. I was like, I have a girlfriend. And they were like, why?

GROSS: (Laughter) Did you kiss?

GREEN: No. No. No, I don't even think we held hands, actually.

GROSS: (Laughter) So what did it mean to have a girlfriend?

GREEN: Nothing. I mean...

GROSS: (Laughter).

GREEN: Yeah, I think it must have been born from the stories I was reading. Like, I was really into, like, series books like "Sweet Valley High" and "The Babysitters Club," and so it must have come from those stories that, like, this is what you do. And I was, like, all right. I'll give it a try.

GROSS: Do you remember the first time you fell in love for real?

GREEN: Oh, yeah. Yeah, that was in college.

GROSS: Did the OCD get in the way of that?

GREEN: It got in the way of it in the sense that it's really difficult, I think, for anyone who is close to someone who's in terrible psychic pain to be near that pain for a lot of reasons. One, you want to take it away. Two, it's just difficult.

And so it was a problem, especially - we dated for a few years, and I think it was a problem especially at the end of our relationship because I would lose a lot of myself, my ability to pay attention to the world outside of myself to these, you know, thought spirals. And I wouldn't be able to pull myself out of it enough to be a good partner or to be a good friend, even. And that was definitely a problem.

GROSS: "The Fault In Our Stars," the one where - is written from the point of view of a teenage girl who has - it's stage 4, I think, cancer...

GREEN: Yeah.

GROSS: So my understanding is that's based in part on one of your fans who actually was dying of cancer.

GREEN: Yeah. My friend, Esther Earl - she died of cancer in 2010 when she was 16. And she was a really involved member of the community that grew up around the videos that my brother and I made and was really involved in our charity projects and became a friend of mine. And yeah, and she died in 2010. And I kind of wrote "The Fault In Our Stars" mostly in the two years after her death.

GROSS: What were some of the things you took away from her life and death that you put in the book?

GREEN: Esther was just uncommonly empathetic. I don't know that that was because she was sick. I think it was partly because she was - you know, some people are just extraordinary. She was incredibly - in the same way that Aza can't pay attention to the world outside of herself, Esther was extremely tuned into the world outside of herself.

You know, the other question, I guess, that emerged for me in the wake of Esther's death was whether a short life can still be a good and a fulfilling life. And I needed to feel like it could be, you know? I needed to feel like Esther had had a good life. And I wrote the book in some ways, I think, in that hope, almost like a prayer that a short life can still be a good life.

GROSS: Did writing the book convince you?

GREEN: (Laughter) That's a good question. Yeah, I mean, I don't know that writing the book convinced me, but I do believe that.

GROSS: You have two children. Is your point of view in your writing shifting a little bit from the teenager to the parent?

GREEN: Yeah.

GROSS: I mean, the parent in the new novel is very - I find her a very sympathetic character. I mean, she clearly, like, loves her daughter so much and is trying so hard not to be the intrusive parent, you know, to have the right amount of connection and distance. But, you know, it's always so hard to find. And as Aza says to her at one point - Aza says to her mother, I'm doing my best, but I can't stay sane for you.

GREEN: Yeah, yeah. I mean, I think as parents, we desperately want to take pain away from our kids, and we want to - I want to save my kids from all the hurt that the world has in it - and you can't. And there's so - that's so difficult. It's so hard to reconcile yourself to that. I do think that I have become much more interested in parents as characters since I became a parent. Like, I used to shuffle all the adults out of my books as quickly as possible. And now I'm like, hold on a second. Let's listen to your mother first. Your mother might have a point here.

GROSS: (Laughter).

GREEN: And I do think that is probably a result of this change in my life that has caused me to suddenly be tremendously sympathetic to the parental point of view.

GROSS: And your kids aren't even teenagers yet.

GREEN: No, God, no. They're 7 and 4, so I have a long, long way to go.

GROSS: (Laughter) So I read that you said you were bullied when you were in - I don't know - junior high or high school - anything in particular you were bullied for, you know, that you were mocked for?

GREEN: I mean, I don't really know. They don't seem to need a great reason.

GROSS: (Laughter) They don't tell you as they're reading you up.

GREEN: Right, yeah. It wasn't - that would have been nice, though, if they could have, like, sent a note that just explained, like, here are the three things you're being bullied for. And if you could work on these three things, then we'll stop.

I think I was different. I was very nerdy. I struggled socially partly because I was really stuck inside of myself. And I think I was at times kind of an annoying kid because I was, you know, a little obsessive and perpetually nervous. But none of that justifies the bullying that happened. It - yeah, it was difficult, and the middle school years especially were extremely difficult for me. And I did have friends, and I was very grateful for those friends. But the bullying was scary and difficult.

GROSS: Did you fight back?

GREEN: No. This is going to surprise you, Terry, but I'm not really super able to fight back.

(LAUGHTER)

GROSS: I never would have expected that.

GREEN: Yeah. I'm not a boxer.

GROSS: So explain what nerd fighters are and what that expression means to you. And do you wish you had that expression when you were a teenager?

GREEN: Yeah. Nerd fighters are people who fight for nerds and fight for nerd culture. It's the term used by people who are in the community that grew up around the videos Hank and I make. And I do wish that I'd had a community like that when I was a kid. And I hope that that community for a lot of young people can be a way of connecting with people who may not live in the same place as them but who have the same interests as them. And so they can feel, you know, not alone in their enthusiasm for Harry Potter or science or whatever it is.

And yeah, I do wish I'd had a community like that as a kid. And I hope that our community can be that for some people. But I also think that there's still a lot of bullying among kids these days. And because of cyberspace, there's no way to be free from it because people can always reach you through your phone or through your computer, and that's really scary. And I hear every day from kids who feel really alone and really afraid because there's no break from the bullying.

GROSS: When did you realize you wanted to write?

GREEN: Well, I always liked writing but I thought of it like being an astronaut or being a professional athlete or something. I never thought of it as a realistic career goal. And in some ways, I still have a day job. And I like having a day job. I like going into the office in the afternoon and working on the online video stuff that we make. But after I decided not to go to divinity school, I started working at this magazine called Booklist. I was an assistant there mostly doing data entry. But it - Booklist reviews like 400 books every two weeks, and all those books were written by somebody. So that's when I started to feel..

GROSS: (Laughter) But were they read by anybody is the question.

GREEN: (Laughter) Yeah. Not all of them, certainly. But that's when I started to feel like, OK, well, being - it's not quite like being a professional athlete or being an astronaut. Like, this is something that regular people do. Lots of people write books. And that's when I started to feel like maybe I could write a book. And at the same time, I started reading a lot of young adult books, and I really loved them. And I thought, well, that would be a great place. Like, that would be such a cool place to publish. And so when I was writing my first novel, I was kind of hoping that that's where it would end up and it did.

GROSS: Why were you starting to read a lot of young-adult books then?

GREEN: I think partly because I was the youngest person at Booklist, so I was the closest thing they had to a young adult.

GROSS: Oh, they asked you to read the young-adult books?

GREEN: Yeah, yeah.

GROSS: Oh, oh.

GREEN: But I also think...

GROSS: So you were reviewing young-adult fiction and then decided you wanted to write it too?

GREEN: Yeah. Yeah.

GROSS: Why did that seem like a good fit?

GREEN: Well, I mean, there are a bunch of reasons, I think. I like the way that young-adult books are published. I like that science fiction and mystery and romance all live on the shelf together, you know, that they're - the genre separations that you see in books for grown-ups aren't there in the same way, also why books tend to hang around because of support from librarians and teachers. And that was really appealing to me.

But in terms of character and readers, it's just, you know, it's a privilege to have a seat at the table in somebody's life when they're forming their values. And that's, for me, what my experience was as a teen reader. And, you know, I hope that my books can be part of that conversation for teen readers today.

GROSS: John Green, it's been great to talk with you. Thank you so much.

GREEN: Oh, thank you.

BIANCULLI: Author John Green speaking to Terry Gross in 2017. His latest young adult novel, "Turtles All The Way Down," has just come out in paperback. Coming up, linguist Geoff Nunberg has some human thoughts about computer algorithms and when they go wrong. This is FRESH AIR.

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