MR. KOJO NNAMDIFrom WAMU 88.5 at American University in Washington, welcome to "The Kojo Nnamdi Show," connecting your neighborhood with the world. So a man walks into a bar -- or was it a chicken that crossed the road? Or maybe it's a group of people trying to screw in a light bulb. We've all listened to countless jokes that start with one of those very lines. But our laughter at the end of the punch line depends on more than whether or not we've heard it before.

MR. KOJO NNAMDITo understand good humor, you have to take a close look at a complex set of processes in our brains involving not only our cognitive abilities but also the parts of our mind that deal with conflicting emotions. Combined, they determine why one joke falls flat but another gets a laugh. Joining us this April Fools' Day for a serious look at what makes something funny is Scott Weems. He is a cognitive neuroscientist and author of a new book called, "Ha!: The Science of When We Laugh and Why." He joins us from studios in Little Rock, Ark. Scott Weems, thank you so much for joining us.

MR. SCOTT WEEMSThank you very much for having me.

NNAMDIIf you have questions or comments about this issue, give us a call at 800-433-8850. What elements do you think are important to a good joke? You can also send us an email to kojo@wamu.org or shoot us a tweet, @kojoshow. The number again, 800-433-8850. Scott, there's a quote in your book that reads, "It is more enjoyable to read a humorous book than to read one explaining humor." We all know what it's like to hear a good joke. So why do you think it's important for us to understand the science behind what's making us laugh?

WEEMSYeah. I mean, I like that quote. There's another quote by E.B. White, who said that dissecting jokes is like dissecting frogs. Your target always dies in the end. And, I mean, to a certain extent, that's true. So I think we need to be a little careful when we look into humor because let's not kill what we're looking at. It's just fun, so we need to appreciate that first.

WEEMSBut at the same time, I mean, it's not like humor is some giant mystery that we will never understand. We understand -- we study things like painting and sculpture and these other arts, and yet, I mean, we master them through practice. But we still can study things like contour and line and form with those arts. There's no reason why we can't look at the same things with humor and try and understand why we laugh. It's an important question.

NNAMDIIt wasn't a clever pun or a witty one-liner that got you thinking about the science behind humor. It was comedian Lenny Bruce and his genre of stand-up comedy in the 1960s. Let's get a sense of what his humor was like, Lenny Bruce, that is. Here he is on a "Steve Allen Show" talking about his wife, whom he'd recently divorced.

MR. LENNY BRUCEYou know, I really miss her. I don't want some sharp chick that can quote Kerouac and walk with poise. I just want to hear my old lady say, get up and fix the sink, it's still making noise.

NNAMDIScott Weems, why did Lenny Bruce's comedy routine get you wondering about the science behind humor?

WEEMSYeah, I think Lenny Bruce is a fantastic example because he doesn't tell traditional jokes. In fact, I think that was from the Carnegie Hall performance from 1962. And, in that performance, he actually makes a point of saying, I'm not telling any jokes. And he finally tells one at the very end that, like, 17 minutes into it, he still has not gotten to the punch line. And he never really finished because that just wasn't his style.

WEEMSWe laugh at a lot more than just jokes. Jokes are a lot more than chicken crossing the road or, you know, how many people does it take to screw in a light bulb? These are very -- these are very exact things when really we laugh at all sorts of things that are funny and that are sometimes just awkward and confusing for us. And so it -- Lenny Bruce got me thinking because I wanted to understand why he was so successful and why we laugh so much when so little of what makes us laugh is a traditional joke.

NNAMDIYou quote Lenny Bruce as saying, "All laughter is involuntary." Are we conscious of the all the work our brain is doing when it processes a joke? How much do you think is happening behind the scenes in our subconscious?

WEEMSYeah, I mean, it's kind of -- you can't fake a good laugh, right? I mean, you can tell if someone's fake laughing. And if someone around you is fake laughing, then, you know, you're not going to laugh either. And I think that's because -- and it sounds, you know, cliché. But so much of our -- so much of what we do is below the surface when it comes to the way think. And in some ways, I -- some people think of the brain working like a computer, which is very linear and progressive. I mean, you've got input, output, and a central processor.

WEEMSBut that's not how our brain works. I mean, it's an okay metaphor, but really what's happening is the brain is working through the complexities of life every day. It's just chaos in there. Even when you look at brain studies of one area lighting up or the other, these are one, two, maybe 5 percent differences. In reality, it's just -- if you liken the brain to the world, it would just be world war all the time, just craziness activity all over the brain. And that's good. That's healthy. It means we're mentally active even when we think we're not.

NNAMDIIf you're just joining us, we're talking with Scott Weems. He's a cognitive neuroscientist and author of a new book. It's called, "Ha!: The Science of When We Laugh And Why." We're taking your calls at 800-433-8850. What kind of humor do you appreciate most? You can also go to our website, kojoshow.org. Ask a question or make a comment there.

NNAMDIScott, you identify three stages of the brain that you say are crucial for our understanding of humor. You call them constructing, reckoning, and resolving. Let's figure out how each of these works by way of an example. In the film, "Animal Crackers," Groucho Marx a, well, now really famous joke. Let's listen.

MR. GROUCHO MARKSOne morning, I shot an elephant in my pajamas. How he got in my pajamas, I don't know.

NNAMDIWhat is your brain -- what is our brain doing when we hear this joke? I mean, and it makes me laugh despite the fact that I've heard it a million times.

WEEMSOh, yeah. And I've definitely heard it a million times, but I still love it. And we still use that example because, I mean, Groucho Marx, in the course of just, you know, a dozen words or more, he just sends our brain going in one direction and then jolts it away and takes it another place.

WEEMSAnd so, I mean, if you want to break it down into the three stages that I talk about, you don't even need to be technical in giving them names. It really just comes down to setting up an expectation and then violating that in some way. So, I mean, who's wearing the pajamas in that line really depends on how far along you are, right?

NNAMDIYep.

WEEMSIn the beginning, it's Groucho. And in the end, you're trying to imagine an elephant wearing pajamas, which isn't an easy thing to do. So, in the course of just a dozen words, he makes you imagine one thing, shocks you out of it, and then basically makes you resolve it to come up with what is, in the end, kind of an impossible thing to do, which is imagining an elephant in pajamas. And I think that's why we love it.

NNAMDIHow is it that three different brain stages could be at play in such a simple clip?

WEEMSI know. I mean, you know, certain jokes are longer. So, I mean, I would say that that line is great 'cause it's so fast. But, I mean, take another line, like what might be a Jay Leno kind of standup where he says, lawyer testifies in horse suit. You know, that's a kind of -- it might make you giggle if you read that. You know, you think, oh, that's funny.

NNAMDII get it.

WEEMSBut it's not so funny if it's just lawyer testifies in suit. I mean, that's equally ambiguous, but the real pleasure -- you got to have that destination, too. That joke's got to take you someplace new. In the horse suit joke, that something new is imagining a lawyer being held in contempt of court 'cause he's wearing, you know, a horse head and a, you know, furry outfit or something. So, yeah, I mean, these stages of processing can happen very fast. And I think that's adaptive. Our brains work that way because they have to. We're surrounded by so much that doesn't make sense, and not just jokes.

NNAMDIWell, the Groucho Marx joke is also short, a characteristic of all Henny Youngman jokes.

WEEMSHmm.

NNAMDIBut a psychologist that you mentioned, Richard Wiseman, actually had a character limit for a funny joke, 103 letters or less, which means that, if it's a good joke, then today we would be able to tweet it. Why do you think brevity is so important?

WEEMSYeah, I love the fact that that magic number is so close to the maximum number of a tweet. And you're right. I mean, the shorter a joke is, the better. And that's because all that extra stuff just gets in the way. I mean, really, you're just looking to set up that expectation and then be shocked out of it. And so extra stuff doesn't help. It really just kind of slows you down on that progression.

WEEMSAnd so, I mean, there were some other interesting things that Wiseman found. And you get this any time you look at lots of different jokes. He found, for example, the funniest animal is the duck. So, if you include a talking animal in your joke -- a horse isn't so funny, but a duck is. And he found that out just by looking at a lot of jokes. So there's a lot of things you can learn by kind of looking at these jokes a little more closely.

NNAMDIOn to the telephones. We'll start with Jen in Washington, D.C. Jen, you're on the air. Go ahead, please.

JENHey, Kojo, great show as usual. As an actor, what we generally fundamentally rely upon when we're doing comedy is rhythm. And if your rhythm's off, people aren't going to laugh. And even if it's a sight gag, there's rhythm involved. There's rhythm involved in all of it. But specifically, in comedy, if your rhythm's off, you can really painfully fall flat on your face. And I -- I was wondering if you could talk about what's happening in the brain with respect, specifically, to rhythm.

NNAMDIAnd you should know that, as a part of this book-writing project about the science of when we laugh and why the book called "Ha!" that our guest Scott Weems did some standup himself. So he can talk about rhythm. I'm not sure from an expert standpoint. But go ahead, Scott.

WEEMSCertainly not as an expert standpoint. I did. I performed this -- you know, I lived in D.C. when I wrote the book and -- or just outside of D.C. -- and so I performed at Magooby's, which is just between here and Baltimore. And I don't want to say that I bombed, but, I mean, I got to be real with myself.

WEEMSSo, yeah, I did not do well. And then part of the reason why -- yeah, timing is so difficult. And there's a saying that, you know, to become a master at an art like humor, you need to follow the rule of five "P"s...

NNAMDIMm hmm.

WEEMS...which is that you practice and practice and practice and practice and practice. So, yes, I think understanding the science is good. But then practicing is how you get the timing. As far as what happens in the brain when you're getting that timing, the funny thing is I don't think anybody knows. Part of that reason is that you can't reduce humor to a simple formula or this is how long you should wait before you get to the punch line kind of thing 'cause any time you try and measure it, that falls flat. And people have tried.

WEEMSI think it was Salvatore Attardo, was a psychologist from Britain, who did that. He basically measured, as much as he could, as people told jokes, you know, the timing, the pauses, the inflections, things like that. Nothing wound up being significant. So nothing, like, was the sure tell of a joke -- the only exception being something like irony.

NNAMDIHmm.

WEEMSSome studies have found that irony you can spot a little easier than other things. But, otherwise, there's no magic cue. And I don't think we even know in the brain what's happening with the timing. That's one of those things that comes with practice. It's the other ingredients, like conflict, that you can learn to play with and then master that over time.

NNAMDIJen, thank you very much for your call. You, too, can call us at 800-433-8850. Do you have a favorite joke or comedian? Let us know, 800-433-8850. Scott, in reality, Groucho Marx's quip doesn't make a lot of sense. In fact, a lot of jokes have absurd characters and storylines, like chickens crossing roads or elephants in cherry trees or like this joke from your book.

NNAMDIA bear walks into a bar and approaches the bartender. He says, a martini. Dry. The bartender asks, what's with the pause? I don't know, the bear replies. I was born with them. Why do you think our brain is able to sift through the parts of jokes that don't make sense and identify what's humorous?

WEEMSYeah, I mean, I love that joke because, I mean, implicit in that is, shouldn't the bartender have said, whoa, there's a bear in my bar.

NNAMDIYeah, right.

WEEMSI mean, it's not very funny, but if this is real life, that's exactly what's going to happen. And you get all sorts of jokes about, like, talking penguins and, you know, and, like I was saying earlier, you know, if you have talking animals, ducks are funnier. And part of that is that, when you engage in a joke or you accept that humor is taking place -- and that sounds very scientific.

WEEMSBut if you accept humor is taking place, then you accept that certain incongruities, certain things you'll give a pass to because you just understand, hey, that's part of being a joke -- but certain things you realize are part of the punch line. I think that's one way that, like, elephant jokes still survive, even though they're not terribly funny. Like, how does an elephant hide in a tree? It paints it toenails red. Oh, it has to be an apple tree. This is -- I'm a scientist. I'm not paid to tell jokes.

WEEMSThis is why I fail. Anyway, you know, elephant jokes, things like that, you accept a certain level of incongruity. But then they also don't fit, and that makes them a little bit funnier. And studies have actually found that when you include talking animals and these extra incongruities in your jokes that it's funnier because we like the fact that kind of we're being told this is a joke, and you're kind of getting your brain ready for something to not make sense.

NNAMDIScott, while we all get Groucho Marx's famous joke, I doubt that it made very many of us laugh out loud. What in the brain explains the difference between getting humor and actually reacting to it with laughter?

WEEMSYeah, so there's one part of the brain in particular that everybody should know and might have heard of already, and it's called the anterior cingulate. It's not on the surface. It's a little beneath, and it's essentially what we would consider our conflict detector. So the brain has a lot of different modules. And these modules are very often arguing among themselves on how to process whatever, you know, we're thinking about at the moment.

WEEMSThe anterior cingulate is essentially the region that kind of helps work through these conflicts and confusions of not always knowing what to do. We're not like a computer where we -- which has a central processor. We don't have a central processor. So the anterior cingulate is basically the region that has to work things through.

WEEMSAnd so we see the anterior cingulate is very active for jokes but for other things, too, like when we get that spine down -- the chill-down-the-spine feeling when we listen to very emotional music or something that just moves us very emotionally that we feel this kind of epiphany.

NNAMDIMm hmm.

WEEMSThe anterior cingulate is very active for that, too, because we're essentially feeling that shock of, whoa, this means something to me, and rearranging kind of how we're looking at the world. If we're listening to music and it suddenly shifts keys, this is something the anterior cingulate deals with. It's like, that doesn't make sense, and it kind of warns us. With jokes, that just happens sometimes very fast.

NNAMDIHave a lot of callers who want to join this conversation, so I'll go to a couple of them right now. I'll start with Chris in Potomac, Md., and then Chen in Bethesda, Md. But, first, here is Chris. You're on the air, Chris. Go ahead, please.

CHRISYeah, hi. Thanks for taking my call. Back sort of in the third quarter of the last century, when I was in college, we studied a book by Henry (word?) on humor. And one of the things that always struck me that he said was that humor is often related to what causes pain comforts other people, like slipping on a banana peel. You also have primitive people who will laugh if somebody is wounded, sometimes even fatally.

CHRISAnd then you also have people who laugh as if they were actually and undergoing humor when they're embarrassed. Personally, I sort of prefer the ironic, like, puns, observist humor, things that deflate the pompous and incongruity. But I was curious what your guest might have to say about the humor related to other people feeling pain and being injured.

NNAMDIAnd, Chris, thank you very much for your call. I'm going to add to that, Scott Weems, what Chen in Bethesda, Md. has to say. Chen, you're on the air. Go ahead, please.

CHENSure. My comment is very similar to that. But I thought about this a lot as well in that it always seems like suffering is a lot funnier than being happy. So, for example, if someone said, I've got such a great wife, there's nothing funny about that. But if you say, well, you know, why did I get married, that always kind of seems funny. And kind of related to that -- and I don't mean as any kind of controversial way whatsoever -- but I found that black people are the funniest people I've met during my lifetime.

NNAMDIAnd why do you think that is?

CHENYou know, I guess you could take somewhat of a political view, and maybe they've had a lot more suffering in their lives. But I can't really figure it out. They're just that some of the most genuinely funniest people I've met were black. I'd be curious if you have any view on that.

NNAMDIScott Weems, whether or not the suffering of black people has to do with what our caller feels may be an enhanced sense of humor certainly among professional comedians.

WEEMSYeah, so, first, about just the whole why is it funny sometimes when tragic things happen or -- I mean, there's an old saying that, if you fall down a manhole, it's funny, but if I do it it's a tragedy. And, I mean, it's linked with something called superiority theory of humor, which is kind of we laugh at what makes us feel better at ourselves.

WEEMSBut I think really it comes down to, again, a matter of conflict, and we're not sure what to make of a situation. And to use an example, so, like, the "Jackass" movies, Johnny Knoxville on MTV.

NNAMDIYep.

WEEMSHe's done great with that. And, you know, so, for example, a bit might be him wearing a chicken suit and being hit by a car. And as much as I don't like to admit it, I probably would laugh if I watched that. But if I went in the parking lot today and just hit the first person I saw with my car, I don't think anybody would call that funny. And I think the reason is when Johnny Knoxville does it, there's another message there that there's no actual intent to harm.

WEEMSSo if you see somebody, like, fall down a manhole and actually, like, kill themselves or break a limb or something, I doubt we would laugh. But if we realize that there is the extra message of there's no intent to harm, that there's kind of a paradox there, a violence but not violence, you know, Three Stooges kind of syndrome, then you approach funnier, which is why I think, you know, some things are offensive to some people. Some things are funny to others. And we all have a different threshold for where our comfort lies in that use of (unintelligible) violence.

NNAMDILater in the broadcast, we'll talk about the trouble that Gilbert Gottfried got into in this situation where people's suffering was definitely not funny.

WEEMSMm. Yes. Yes.

NNAMDIBut now we've got to take a short break. When we come back, we'll continue our conversation with Scott Weems about his new book. It's called "Ha!: The Science of When We Laugh and Why." If the phone lines are busy, shoot us an email to kojo@wamu.org or go to our website kojoshow.org and join the conversation there. I'm Kojo Nnamdi.

NNAMDIWelcome back. Our guest is Scott Weems. He's a cognitive neuroscientist. He's also the author of a new book. It's called "Ha!: The Science of When We Laugh and Why." He joins us from studios in Little Rock, Ark. Scott, today, comedians don't sound much like Groucho Marx, and few jokes seem to have punch lines. Take comedian Louis C.K., for example. Let's listen to a part of his performance on HBO in 2005.

MR. LOUIS C.K.Know what's amazing to me? You can name your kid anything you want. Isn't that incredible? There are no laws. There should be a couple of laws. None. You can literally name your kid anything. You can name your kid a name with no vowels if you want like -- just 40 "F"s. That's his name -- go clean your room.

NNAMDILouis C.K. Scott Weems, given what we've learned about how our brain processes humor, why do so many of us find Louis C.K.'s style of comedy funny?

WEEMSYeah, I mean, I love the fact that you picked Louis C.K. because he's right now I think at the top of humor. If you ask comedians who they think is kind of doing -- running the field, who's got it right now, it's Louis C.K. And I think he reflects the times. If you look at, like, humor, you know, 10, 20 years ago -- I mean, I grew up watching people like Robin Williams and Howie Mandel. They were very over the top. It was loud. It was fast. It was bam, bam, bam.

WEEMSBut Louis C.K.'s -- I think he reflects the way we act now a little bit better. Like, take for example he was on Saturday Night Live this weekend. And he shared some great jokes about what it's like to go to his children's recital and how much he loved his daughters but how painful it was to sit through an hour or two of a bad play or bad singing or something. And this is what we look for now, both in humor and our relationships, and honesty but a lack of pretense. And I think that's why Louis C.K. is so successful.

NNAMDIToday, it seems more common to share a funny YouTube video than a joke that involves a setup and a clever punch line. Why does it seem that few people tell traditional jokes today?

WEEMSYeah, I mean, I kind of joke in my book about the traditional joke being dead. I would never say it's dead, but I'd say it's gravely injured. And part of that is social media and the Internet and just the fact that it's so easy to put absurd humor out there. I mean, one of my favorite things -- and I go on every day to log on -- is Garfield without Garfield. And it's genius in a very weird way that some guy basically took Garfield cartoons and then took out the cat.

WEEMSSo it's just Jon Arbuckle saying very existential and very depressing and sad things. And it makes me laugh out loud. And it's a good example of absurd humor that we're so used to now that it gets you thinking -- or maybe not thinking at all because it's so crazy. And this is what we like now, too. And this is also reflective of the time where it's kind of an absurd time maybe.

NNAMDIYou started this book with the obituary for the joke from The New York Times in 2005. You say that the end of the joke started with Lenny Bruce?

WEEMSYeah, Lenny Bruce. He was the master of the riff. And he so often is associated with jazz that -- I mean, he didn't perform jokes. He didn't really practice them. He just riffed. And, you know, it's so hard to repeat so much of what he said because it just doesn't make sense.

NNAMDIOf course, like Richard Pryor, yes.

WEEMSYeah, yeah, you just -- you take it out of its context, and it fails. And it's because he was like a musician. You know, musicians don't just practice the letter "C." They just -- they play their notes, and that's what he did with comedy.

NNAMDIHere's David in Edgewater, Md. David, you're on the air. Go ahead, please.

DAVIDHi. I've often heard that laughter is the first order of acceptance. And could that be destructive? I mean, there's things like "The Simpsons" and "Family Guy" that are out there that touch on feelings that are -- that really probably shouldn't be jokes, like pedophilia and things like that. Do you feel that maybe some kind of jokes can be destructive?

NNAMDIScott.

WEEMSYeah, I mean, it really depends on how you take them, I think. Yes. I mean, certainly no one that I know would say pedophilia is good or anything like that. But just because you make a joke about it I don't think is giving implicit acceptance to that. And here you can take that to a really extreme example and use the joke the aristocrats as an example.

NNAMDIMm hmm.

WEEMSThere's no single word of that joke that I could share on the air at all.

NNAMDIThat's true.

WEEMSNot at all.

NNAMDIWell, we'll talk about that -- hold that story for a second because this gives me the opportunity to go to the whole Gilbert Gottfried thing. Conflicts makes for good humor. But as comedians know, jokes can also cross a line, offend the audience. You tell the story of comedian Gilbert Gottfried who turned off his audience after telling a joke about the 9/11 terrorist attacks just weeks after those attacks had occurred. Can you tell us a little more about that story and why, in the eyes of the audience, Gottfried went too far?

WEEMSYeah well, at first he did -- this was, I think, three weeks after the tragedy of 9/11. And if you remember -- I mean, we all remember actually, those of us that were around. But there was no comedy then. Sporting events were cancelled. The Oscars were postponed. Basically anything that was fun or that was light we just kind of put aside for a bit because we needed to reflect on what had happened.

WEEMSAnd then there was the Hugh Hefner roast that was scheduled for about three weeks after. And it was basically supposed to be an event of comedy and no one knew how to deal with it. And so they -- I'd say that a lot of comedians did what was maybe not the healthiest thing -- but it was their only choice -- that they avoided the topic. So there were a lot of very safe jokes.

WEEMSAnd, you know, the target was Hugh Hefner. So he's got a few, you know, easy points you can joke about. But Gilbert Gottfried, you've got to respect him at least for his tenacity, that he didn't do that. He told a joke. He said, yeah, you know, I need to leave early tonight. I've got an early flight to Los Angeles, but it's got to stop over at the Empire State Building.

NNAMDIBoo, boo, boo.

WEEMSBoo, yeah, oh, yeah. So first silence, and then boo and then, too soon. Just basically, the crowd turned. It was ugly. And so, I mean, at that point, you've got two choices, right. You know, you can either walk off and say, yeah, I should have...

NNAMDIAnd slink off the stage.

WEEMSYeah, or you can go the exact opposite way and...

NNAMDIAnd that's what he did.

WEEMSThat's what he did. And you've got to love him at least for just the -- you know, you might like the joke, don't like the joke. He told the aristocrats joke...

NNAMDIOh yeah,

WEEMS...which is the most offensive joke in the world. And it is because that's -- if there's a more offensive version, then the aristocrats will morph into that. It's just the most offensive joke you can come up with.

NNAMDIBut it's got a great punch line.

WEEMSIt does. I mean, the -- you can look it up or watch the movie. I really recommend, if you're not offended, you check out the movie because they made a movie of that performance and the joke in general. And, I mean, he really -- I don't know if I -- I don't think I shared this. I don't know. But there's a saying, if you have a point, tell a story.

WEEMSBut if you have more than one point, tell a joke. And that's what Gilbert Gottfried was saying. He was saying, you know, just because we talk about this event, this tragic, tragic event, doesn't mean that we're making light of the people who died, just the opposite. I think ignoring it is the worst thing. And you can agree or disagree with that statement, but you can't say that he had malice in his mind when he told the joke.

WEEMSAnd so it's really tough because you've got to get in the comedian's mind of what is he or she trying to accomplish by telling the joke? If it's to insult a certain population or, you know, to be sexist or racist or whatever, then that's clearly bad. But if it's not, it's just to shed light on a topic that maybe needs light shed onto it. I don't think that's a bad thing.

NNAMDIYeah, indeed, you point out that good humor involves some kind of conflict. And we see a lot of comedians make jokes about controversial topics. Comedian Dave Chappelle often confronted racial stereotypes in his jokes. Let's listen to a clip from his show at the Lincoln Theater here in Washington, D.C., which is his hometown. This was back in 2000.

MR. DAVE CHAPPELLEI left D.C. in the '80s. It was not like this in the '80s when crack was going on. Remember when crack was going on? Black people be looking at D.C. from Virginia with binoculars and (bleep). Well, that looks dangerous. Not yet.

NNAMDIThat was 14 years ago, but Dave Chappelle's joke still touches on a conflict, changing demographics, that's still relevant in Washington. It's even an issue in our Democratic mayoral primary that's taking place today, Scott. Why would jokes that center on conflict like this actually make us laugh more?

WEEMSYeah, I mean, Dave Chappelle is great because there's not many people that can tackle the issues that he does with his comedy. I mean, he's -- he'll tackle race right on. And, you know, you look at the same thing -- Ralphie May is a comedian that does it now, too. When you go back in time to people like Richard Pryor, which is a little closer to Lenny Bruce's time, Richard Pryor didn't become famous until he realized he didn't have to be Bill Cosby.

WEEMSBill Cosby was about the same era, and he was telling very safe jokes, as he always has, and done great for it. And you've got to love Bill Cosby for it. But, let's face it, Richard Pryor is not Bill Cosby. And so when he finally realized, hey, you know, race is a big part of my life, and racial discrimination is a big part of my life. Why not make it part of my act?

WEEMSAnd I think that's great. It's tackling a problem, which is what Lenny Bruce did too, except he talked about drugs and sexism and things like that, too. But you're getting at these issues, and you've got to have some edge when you do it. And, I mean, David Chappelle, he has some edge, and I think he uses it so beautifully.

NNAMDILet's go to Katherine in Greenbelt, Md. Katherine, you're on the air. Go ahead, please.

KATHERINEI just wanted to share that the worst punishment I ever received in my life -- and I was 15 -- was when I told an ethnic joke in home. And I learned values then. I was grounded for two weeks. And that is the severest punishment I ever got because my father just said, that is not funny. We were Irish. If you want to tell Irish jokes, go right ahead because we love to laugh at ourselves. But we don't laugh at any other nationality or any other ethnic group. And it was a profound experience.

NNAMDII'm glad you brought that up because, Scott, experience tells us to keep it to ourselves when we might find something funny. But because we're in an environment where a joke would not be appropriate, we learn to keep it to ourselves. How does our mind take social expectations into account when reacting to humor? Because Katherine's parents obviously felt that what she'd said on that occasion was completely inappropriate.

WEEMSYeah, I mean, I think social expectations are a big part of it. If your goal is merely to violate an expectation, to shock, I don't enjoy that kind of humor either. And, I mean, I like pretty much all kinds of humor. I really surround myself by it. But, I mean, if the point is just to insult a group or something like that, gosh, I don't think you could even technically call that a joke. It's just -- I don't know, it's just racism or sexism or something like that.

WEEMSSo, I mean, depending on the joke, yeah, it might've been completely appropriate to say, no, no jokes like that. And I would say, yes, you shouldn't tell jokes making fun of people. And that's not -- you don't just even need to focus on race either. I mean, you can go as far as to look at something like lawyer jokes. Lawyer jokes are incredibly popular, but they're also incredibly violent. How many lawyers does it take to put a roof on a house? It depends on how thin you slice them.

WEEMSI mean, I just -- I threw that one out there quick because there's just too many to count, but, oh my goodness, if someone could take that joke and say Scott Weems advocates killing lawyers and putting them on your roof. And I would say, no, you know, I'm not a big fan of, you know, lawyer killing or any kind of killing. So it really depends on the message. And sometimes that message can be bad and have bad consequences. And that's when the humor should be avoided.

NNAMDIKatherine, thank you very much for your call. We move on to Jessica in Crofton, Md. Jessica, your turn. Oh, here's Jessica. Jessica, you're on the air. Go ahead, please.

JESSICAHi, thank you. I really look forward to reading your book. I was wondering if you touch on anything for those of us with cognitive disabilities or what they call the average person and their humor versus ours as we are more like Data from Star Trek and we take everything very literally. But other people seem to find us humorous. How do you address that in your book, if at all?

NNAMDIScott?

WEEMSYeah, it is interesting. There has been studies that have looked at people with special conditions, like -- I don't know -- autism or schizophrenia, things like that. I mean, even just things, like, lying along the Asperger scale. And, you know, it's interesting. It actually is a good thing when it comes to humor a lot of the time. And here I'm talking about one fascinating study by Paul Pierson, who gave people -- both professional -- I think, no. He just looked at professional comedians -- and gave them personality assessments and found that having a little bit of neuroticism helps.

WEEMSAnd this isn't a pathology. This is actually just along a continuum, so you can either be very stable or very neurotic or, like most of us, somewhere in between. And the funniest people, and the people who kind of most -- I don't know -- skilled at humor, are the ones that are not completely stable. They're a little bit, you know, closer to the neurotic end of that spectrum.

WEEMSAnd you see that all sorts of professions, from -- there was one study that compared all, like, lots of different ones from veterinary surgeons to painters and found that they all -- the most successful people in their craft had a little bit of neuroticism. So I would say some things are good like that. And there have actually been other studies that have looked at very specialized conditions, like autism and schizophrenia.

WEEMSAnd they appreciate humor, too, very different sometimes though. People -- to take autism in example, they like their jokes a little less with anxiety and aggression in them and a little safer. And that's just because we all have some sort of peak edge that we like in our jokes, that edge maybe being a little higher or lower depending on, you know, who you are.

NNAMDIGot to take a short break. When we come back -- thank you very much for your call. When we come back, we'll continue our conversation with Scott Weems. He's a cognitive neuroscientist. His new book is called, "Ha!: The Science of When We Laugh and Why." The number is 800-4333-8850. Do you think dark humor can be funny, even if it's offensive? Why or why not? 800-433-8850. I'm Kojo Nnamdi.

NNAMDIOur guest is Scott Weems. He is author of a new book called, "Ha!: The Science of When We Laugh and Why." Scott Weems is a cognitive neuroscientist. We're taking your calls at 800-433-8850. Have you noticed that your sense of humor changes as you grow older? If so, how? 800-433-8850. You can send email to kojo@wamu.org or shoot us a tweet, @kojoshow.

NNAMDIScott, we got an email from Rachel in Silver Spring, who says, "I found when I see a comedian in person, the group dynamic, many people enjoying something at once, makes me laugh much more than, say, watching the comedian at home on TV, even if I can see the TV audience roaring with laughter. The group dynamic can make even a mediocre joke seem funnier."

NNAMDIScott, you looked at one study where the research subjects found a comedy, "Monty Python's Meaning of Life," to be more funny when there was someone in the room laughing. Why do we get a better laugh out of jokes when we share them with other people?

WEEMSYeah, and we do. We definitely do. If someone near us is laughing, we laugh, too. It's just like we're programmed to do that. I love that study you cited, too, because that was -- what they did is they had the experimenter, herself, laugh, but like as a, you know, she shouldn't be but couldn't control herself. And that really made her subjects laugh, too. It was all part of a, you know, a sham or whatever.

WEEMSAnd so you do definitely see laughter being contagious. And it really depends on a lot of things. The closer people are to you, the more you'll laugh. The better you know them, the more likely you are to laugh. And the more people around you laughing, the more you do. But there's a trick. And that is that if you think the laughter is fake -- so someone's laughing to try to trick you into laughing or, you know, you kind of ha, ha, ha, yeah, then it all falls apart.

WEEMSThen you don't laugh more. Which is I think why you used to see laugh tracks really popular but now not so much. Now we're kind of moving away from that. And I think it's because we figured out the trick. You know, we watch these sitcoms, and we hear the laughter in the background. And we realize, you know, I -- why are they laughing? And then you realize, oh, it's a recording. And so, yeah, you know, so be careful. Don't try and just trick people into it. It's got to be legit.

NNAMDIAnd we got an email from Irene in Franconia, Va., who asks, "Is there a gender component to what's funny? I never found the Three Stooges funny. And I've read that women are less likely than men to enjoy them." Many of us, Scott, are familiar with the stereotype that women are less funny than men. Yet you point to a study that show women actually laugh much more than men, in fact, as much as 126 percent more than men. What does science say about the differences between men and women when it comes to humor?

WEEMSYeah, this is fascinating. And no matter which study I cited and how I talk about it, somebody seems to be upset about it, it seems like, because it's always tricky to talk about gender differences and humor. And it's because you do see some interesting effects. Men outnumber women in professional comedy a lot. And, you know, it might be 12 percent women in professional comedy. But yet women laugh more.

WEEMSAnd we know because scientists -- in fact, a Maryland researcher, Robert Provine, went out and eavesdropped on people for a year. He and his assistants when to coffee shops and subways and measured the number of times they saw people laugh. And women -- put two women in a room, they'll laugh twice as much as two men, I think. So you're trying to reconcile this.

WEEMSAnd part of it -- there's an evolutionary theory for why this is, and it comes down to the fact that sense of humor is really closely linked with intelligence and is a sign of somebody who's worth the effort when you're talking about, like, being a partner. Studies show that women -- the number one thing they look for in a mate is sense of humor. For men, it's closer to, like, number three.

WEEMSSo it could be that men just maybe were raised to be the ones who try and crack the jokes because we're trying to make ourselves, you know, worthy, let's say. And, you know, for people like me that are, you know, not born with movie-star looks, it might be what we've got to deal with, you know. So we just compensate with a sense of humor. And so women look for men who make them laugh. And men like women who laugh more. And so you see these things actually borne out experimentally. Whether that's fully true or not, it's kind of hard to guess.

NNAMDIHere now is Brian in Alexandria, Va. Brian, you're on the air. Go ahead, please.

BRIANThank you for taking my call. This has been very fascinating. I just wanted to call and comment because my son is on the autism spectrum, and he's always had a sort of interesting take on humor. And one of the things that he latched onto early on in his young life were some of the old black and white Abbott and Costello, Marx brothers movies. He would just laugh hysterically at those and repeat those lines over and over again.

BRIANAnd just, you know, he'd use the reference, you know, I shot an elephant in my pajamas last night. He does that maybe several times a week, just sort of blurting out that and the old Abbott and Costello, you know, who's on first? What's on second? And I find hit fascinating that years -- I watched it when it first came out 20 years ago and then watched again recently, the movie "Rain Man," where the character in "Rain Man," is also fascinated by Abbott and Costello movies and constantly repeats, you know, who's on first? What's on second?

BRIANI remember watching that and going, oh, my God, there's some sort of connection. We are in circles where we know a lot of other families with children on the autism spectrum, and they have similar sort of takes on humor, a lot of repetitive. A lot of that old style sort of slapstick Abbott and Costello and the Marx brothers type stuff really connects with kids on the autism spectrum. I don't know if there's ever been a study or something about that, but it's just been my informal observation, again having a child on there, that they just -- he just starts watching it.

BRIANOne of his favorite movies, "Young Frankenstein," and he will repeat lines from that, you know, Abby Normal, just constantly. He almost knows most of the movie by heart and just finds it -- I mean, I find it funny as well. But there's something about kids on the spectrum and the way their brain works that some of that, again, Abbott and Costello -- I'll use that again -- and he just loves that.

NNAMDILet me see what Scott Weems has to say about that. Scott?

WEEMSYeah, that's fascinating, isn't it? And, yeah, I mean, that matches what a lot of research has shown. And, I mean, it's kind of speculative, but in some ways -- I mean, some of that old humor -- and I love, you know, some of that old Abbot and Costello, who's on first? kind of stuff. There's a structure to it. And so people who kind of gravitate towards a structure and then like being pushed out of that just a little bit, they tend to gravitate to that kind of humor.

WEEMSAnd, I mean, I kind of like that, too. It's old-school because it's almost a purer form of humor than some of the more -- I don't know -- very risky or very edgy stuff you see today. I mean, that's kind of outside of a lot of people's comfort zones. And so you get to that old-school stuff -- I love it too because it's kind of -- it's a purer form of that shock.

NNAMDII mentioned dark humor earlier. Some kinds of humor seem to stand the test of time. Stanley Kubrick's "Dr. Strangelove" or "How I Learned to Stop Worrying and Love the Bomb" is considered one of the greatest comedies of all time, even though it was made 50 years ago. Let's listen to a little of one of the more famous scenes when the U.S. president calls the leader of the Soviet Union to let him know that a rogue commander has ordered planes to attack his country.

MR. PETER SELLERSHello? Hello, Dmitri? Listen, I can't hear too well. Do you suppose you could turn the music down just a little? Oh, that's much better. Yeah, yes. Fine, I can hear you now, Dmitri, clear and plain and coming through fine. I'm coming through fine, too? Good, then -- well, then, as you say, we're both coming through fine. Good. Well, it's good that you're fine, and I'm fine. I agree with you. It's great to be fine.

NNAMDIHe, the Peter Sellers character, then goes on to tell him that a nuclear bomb will reach his country in an hour. Even generations born after the Cold War appreciate the dark humor in "Dr. Strangelove." Why do you think some kinds of humor are funny even outside of their historical context?

WEEMSYeah, I mean, that's -- I love the fact that this is one of the top comedies of all time. And wars are fought, and people are killed. And in the end the whole world dies, nuclear annihilation -- and the greatest comedy of all time. So it shows how there's a lot more to humor than just straight-up jokes. But I think, even though we don't live in the same Cold War now as we did back when that film was made, we can understand, we can all relate to the issues really being addressed in that.

WEEMSFirst, there's just the farce of -- I don't know -- the whole thought of winning a military conflict like that. You know, just no one wins. And that's going to be universal. I think we always understand that, you know, whether it's us versus Russia, or who knows who against who knows who, you know, nuclear war, no one really wins. And so that's going to be universal. And then just the futility of dealing with something that's just so unfortunate as, you know, nuclear war but then so very human interaction of an awkward phone call like that, it's a meshing of very real and very surreal, I think, together.

NNAMDIWell, from 50 years ago, I'd like to bring you right up to the present and go back to Gilbert Gottfried again because he also worked for the insurance company Aflac. He played the voice of their ubiquitous duck mascot. And while the company did not fire him over his jokes about the 9/11 terrorists attacks, they did let him go 10 years later after he tweeted jokes about the tsunami in Japan. Do you think that and Stephen Colbert making a similar mistake last week highlights how there might be different rules for jokes on digital media, like emails and tweets, today?

WEEMSYeah, oh, my. Yeah, I think this is very unfortunate. With Twitter, you can put out a though instantly, and that's not always good. You might want to self-reflect. And so I'd say Gottfried probably did the same thing with his tsunami tweet when he -- I forget what the joke was -- but it was offensive to a lot of people. And…

NNAMDIYes.

WEEMS…yeah, he got let go. It probably was too soon, so he should have recognized that. And there's just something that's not communicated by text, that, you know, even if he wasn't -- even if in his mind, he saw that tweet as just not making light of a tragedy, but maybe just a coping mechanism or something like that. Who knows what he was thinking when he sent that. I think it might have been taken better. And the Colbert tweet is interesting, too, because, first, he didn't actually send that.

WEEMSSome poor person, who I suspect is probably looking for a job now after leaving Comedy Central, is probably the one that sent that. It was from the Comedy Central Studios, not him, but equally offensive. And part of the reason why that one was equally offensive was that there was no context. His actual bit where he had that line, he was making fun. He was making fun of anybody that would think that that was an appropriate thing to say, making a racist -- I think it was anti-Chinese.

NNAMDIYes, anti-Asian, yes.

WEEMSAnti-Asian statement, yeah. And, see, I mean, if you see the bit, you say, oh, wow. Yeah, he's definitely calling anybody who would say that or think that, calling them out on it. But when you put that sentence out by itself with no context at all, oh, my gosh, it is a terrible thing to say.

NNAMDIFinally, we go to Doug in Silver Spring, Md. Doug, you're on the air. Go ahead, please.

DOUGHi. Thanks for taking my call. When you started this discussion, it reminded me of an article I read years ago by W.C. Fields about comedy. And in it he says, "After all my years doing comedy, I can tell you what will make people laugh, but I can't even begin to tell you why they will laugh." And he gave an example of a bit he did on stage where he's a husband sitting at home with his wife. It's one of the oldest jokes in the world.

DOUGHe gets a phone call from a friend named Elmer. He repeats Elmer's name a dozen times during the phone call. "What's up, Elmer? Oh, really, Elmer?" Call ends, there's a pause, and then he says to the wife, "That was Elmer." And he said he's done that gag 100 times. He said he's tried every name under the sun, George, Charley, Fred, but, for some reason, if he used the name Elmer, that always got the biggest laugh at the punch line.

NNAMDIWhat's going on with our brains when that happens, Scott?

WEEMSI wish I could say that we have, in our brains, the Elmer center.

NNAMDII guess so.

WEEMSSomething tells me that -- I guess it's April Fools' Day. Maybe I could just make that up, and no one would call me on it. Well, I have no idea. I mean, there's the, you know, E.B. White saying dissecting jokes is like dissecting frogs. You know, both die in the end. And that's kind of an example right there. I don't know if I want to dissect why Elmer is humor -- is funnier. I kind of like a world in where there's a little bit of mystery. And I'll keep that one a mystery.

NNAMDII'm glad you said that because I was about to ask for my final question -- we'll only have about a minute left -- if we understand exactly how our brains process humor, could we then come up with a formula or a computer program that would then develop the world's funniest jokes, and would that be any fun?

WEEMSYeah, well, I will say that I think that humor is up there with intelligence and language and these most creative complex things we do. And so when we understand humor, we'll really understand how our brains tick. We're not there yet, but we've made so much progress in the past five or 10 years. And I can't think of a more fun thing to study and understand to get to know ourselves than humor. I think it's a lot more then something trivial. It's actually very important.

NNAMDIAre you going to try to do standup again?

WEEMSAbsolutely not. I have enough -- I struggle just to share individual jokes in context like these. I'm going to stick with science. But I love -- fortunately, science shows that just exposing yourself to humor is enough. So I'm going to watch as much comedy as I can and leave it to the professionals.

NNAMDIScott Weems, his new book is called, "Ha!: The Science of When We Laugh and Why." Scott Weems is a cognitive neuroscientist. Scott Weems, thank you so much for talking with us.

WEEMSYeah, thank you. It was fun.

NNAMDIAnd thank you all for listening. I'm Kojo Nnamdi.