Aug 13, 2007


Where does our sense of right and wrong come from?

We watch chimps at a primate research center sharing blackberries, observe 3-year-olds fighting over toys, and tour Eastern State Penitentiary -- the country's first penitentiary. Plus, a story of land grabbing, indentured servitude, and slumlording in the fourth grade.


UPDATE: Jad is now a father! If you'd like to know how becoming a parent did or did not change his answer to the thought experiment in the first half of this episode, check out what he has to say, here

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Male:                                     You are listening to ...

Female:                               To Radiolab.

Robert Krulwich:             Hi, I'm Robert Krulwich.

Jad Abumrad:                   I'm Jad Abumrad.

Robert Krulwich:             This is Radiolab. In this hour we're going to examine a sense of moral justice. Everybody knows that sometimes you feel something is right, sometimes you feel something is wrong. We want to know where does that feeling begin, where does it come from, how old is it. We are going to take you from play groups to prisons, some brain scans in between.

Jad Abumrad:                   Can we get started, please?

Robert Krulwich:             Okay, okay. Just going on a bit.

Jad Abumrad:                   Since this is an hour on morality, why don't we start with two morality thought experiments. Are you with me?

Robert Krulwich:             Begrudgingly, yes.

Jad Abumrad:                   This is a famous problem originally posed in 1967 by the philosopher Philippa Foot. There are two parts to this problem, and you're going to have to make a choice at the end of each one.

Robert Krulwich:             Each one, you're going to tell me a story.

Jad Abumrad:                   I'm going to tell you a story and you're going to make a choice. Part one, you ready?

Robert Krulwich:             Yeah.

Jad Abumrad:                   You're near some train tracks. Go there in your mind. There are five workers on the tracks working. They've got their backs turned to the trolley, which is coming in the distance.

Robert Krulwich:             You mean they're repairing the tracks.

Jad Abumrad:                   They're repairing the tracks.

Robert Krulwich:             This is unbeknownst to them the trolley is approaching.

Jad Abumrad:                   They don't see it. You can't shout to them. If you do nothing, here's what'll happen. Five workers will die.

Robert Krulwich:             Oh my god! That was a horrible experience. I don't want that to happen to them.

Jad Abumrad:                   No, you don't, but you have a choice. You can do A, nothing, or B, it so happens next to you is a lever. Pull the lever and the trolley will jump onto some side tracks where there is only one person working.

Robert Krulwich:             If the trolley goes on the second track, it will kill the one guy.

Jad Abumrad:                   Yeah, so there's your choice. Do you kill one man by pulling a lever or do you kill five men by doing nothing?

Robert Krulwich:             I'm going to pull the lever.

Jad Abumrad:                   Naturally. Here's part two. You're standing near some train tracks. Five guys are on the tracks, just as before, and there is the trolley.

Robert Krulwich:             I hear the train coming. Same five guys are working on the track?

Jad Abumrad:                   Same five guys.

Robert Krulwich:             Backs to the train, they can't see it.

Jad Abumrad:                   Yeah, exactly. However, I'm going to make a couple changes. Now you're standing on a footbridge that passes over the tracks. You're looking down onto the tracks. There's no lever anywhere to be seen, except next to you there is a guy.

Robert Krulwich:             What do you mean there's a guy?

Jad Abumrad:                   A large guy, large individual standing next to you on the bridge, looking down with you over the tracks, and you realize, "Wait, I can save those five workers if I push this man, give him a little tap." He'll land on the tracks.

Robert Krulwich:             He stops the train. Oh man, I'm not going to do that. I'm not going to do that.

Jad Abumrad:                   Surely you realize the math is the same.

Robert Krulwich:             You mean I'll save four people this way?

Jad Abumrad:                   Yeah.

Robert Krulwich:             Yeah, but this time I'm pushing the guy. Are you insane? No.

Jad Abumrad:                   Here's the thing. If you ask people these questions, and we did, starting with the first, is it okay to kill one man to save five using a lever? Nine out of 10 people will say.

Female:                               Yes.

Female:                               Yes.

Female:                               Yes.

Female:                               Yes.

Female:                               Yeah.

Jad Abumrad:                   If you ask them is it okay to kill one man to save five by pushing the guy, nine out of 10 people will say.

Female:                               No, never.

Female:                               No.

Male:                                     No.

Jad Abumrad:                   It is practically universal.

Marc Hauser:                   Education level, no effect. Male versus female, no effect.

Jad Abumrad:                   That's Marc Hauser, professor at Harvard. He actually posed the trolley scenarios to hundreds of thousands of people on the internet, found the same thing. Everyone agrees. Then he took it a step further and asked them why. Why is murder, because that's what it is, why is murder okay when you're pulling a lever, but not okay when you're pushing the guy. What he found is that consistently, people have no clue.

Marc Hauser:                   People have no clue. They don't understand what drove their judgments, which were completely spontaneous and automatic and immediate. Once they appreciate the dilemma they're now in of lack of consistency, the whole thing basically begins to unravel.

Female:                               The pulling the lever to say the five, that feels better than pushing the one to save the five, but I don't really know why. There's a good moral quandary for you.

Robert Krulwich:             If, as we said in the beginning, having a moral sense is a unique and special human quality that maybe we, us two humans anyway, you and me, should at least inquire as to why this happens. I happen to have met somebody who has a hunch. He's a young guy at Princeton University, wild, curly hair, bit of mischief in this eye. His name is Josh Greene. He spent the last few years trying to figure out where this inconsistency comes from.

Josh Greene:                    How do people make this judgment? Forget whether or not these judgments are right or wrong, just what's going on in the brain that makes people distinguished so naturally and intuitively between these two cases, which from an actuarial point of view, are very, very, very similar, if not identical.

Robert Krulwich:             Josh is, by the way, a philosopher and a neuroscientist, so this gives him special powers. He doesn't sit back in a chair, smoke a pipe, and think, "Now why do you have these differences?" He said, "I would like to look inside people's heads, because in our heads we may find clues as to where these feelings of revulsion or acceptance come from." In our brains.

Josh Greene:                    We're here in the control room.

Robert Krulwich:             Just so happens that in the basement of Princeton there was this big circular thing.

Josh Greene:                    Looks like an airplane engine.

Robert Krulwich:             180,000-pound brain scanner.

Josh Greene:                    I'll tell you a funny story. You can't have any metal in there, because the magnet. We have this long list of questions that we ask people to make sure they can go in, do you have a pacemaker, have you ever worked with metal, blah blah blah blah blah.

Robert Krulwich:             Have you ever worked with metal?

Josh Greene:                    Yeah, because you can have little flecks of metal in your eyes that you would never even know are there from having done metalworking. One of the questions is whether or not you wear a wig or anything like that, because they often have metal wires in with that. There's this very nice woman who does brain research here, who's Italian. She's asking her subjects over the phone all these screening questions. I have this person over to dinner, she says, "Yeah, I ended up doing this study, but it was asking you the weirdest questions. This woman's like, 'Do you have a hairpiece?' I'm like, 'What does it have to do if I have herpes or not?'" She asked, she said, "Do you have a hairpiece?" Now she asks people if you wear a wig or whatever.

Robert Krulwich:             Anyhow, what Josh does is he invites people into this room, has them lie down on what is essentially a cot on rollers, and he rolls them into the machine. Their heads are braced, so they're stuck in there. Have you ever done this?

Josh Greene:                    Oh yeah, several times.

Robert Krulwich:             Then he tells them stories. He tells them the same two trolley tales that you told before. Then at the very instant that they're deciding whether I should push the lever or whether I should push the man, at that instant the scanner snaps pictures of their brains. What he found in those pictures was frankly a little startling. He showed us some.

Josh Greene:                    I'll show you some stuff. Let me think.

Robert Krulwich:             The picture that I'm looking at, it's a brain looked I guess from the top down.

Josh Greene:                    Yeah, it's top down and sliced like a deli slicer.

Robert Krulwich:             The first slide that he showed me was a human brain being asked the question, "Would you pull the lever?" The answer in most cases was yes.

Male:                                     Yeah, I'd pull the lever.

Robert Krulwich:             When the brain's saying yes, you'd see little peanut-shaped spots of yellow.

Josh Greene:                    This little guy right here and these two guys right there.

Robert Krulwich:             The brain was being active in these places. Oddly enough, whenever people said yes to the lever question, the very same pattern lit up. Then he showed me another slide. This was a slide of a brain saying no.

Female:                               No, I would not push the man.

Robert Krulwich:             "I will not push the large man." In this picture ...

Josh Greene:                    This one we're looking at here, this is-

Robert Krulwich:             It was a totally different constellation of regions that lit up. This is the no no no crowd.

Josh Greene:                    I think this is part of the no no no crowd.

Jad Abumrad:                   When people answer yes to the lever question, there are places in their brain which glow?

Robert Krulwich:             Right, but when they answered, "No, I will not push the man," then you get a completely different part of the brain lighting up.

Jad Abumrad:                   Even though the questions are basically the same?

Robert Krulwich:             Mm-hmm (affirmative).

Jad Abumrad:                   What does that mean? What does Josh make of this?

Josh Greene:                    He has a theory about this. A theory not proven, but this is what I think the evidence suggests.

Robert Krulwich:             He suggests that the human brain doesn't hum along like one big unified system. He says maybe in your brain and every brain, you'll find little warring tribes, little subgroups. One that is doing the logical accounting kind of thing.

Josh Greene:                    You've got one part of the brain that says, "Huh, five lives versus one life? Wouldn't it be better to save five versus one?"

Robert Krulwich:             That's the part that would glow when you answer, "Yes, I'd pull the lever."

Male:                                     Yeah, I'd pull the lever.

Robert Krulwich:             There's this other part of the brain which really, really doesn't like personally killing another human being, gets very upset at the fat man case, and shouts, in effect.

Male:                                     No!

Male:                                     No!

Jad Abumrad:                   It understands it on that level and says ...

Male:                                     No!

Male:                                     No!

Jad Abumrad:                   ... no, bad, don't do.

Female:                               Never, I don't think I could push.

Female:                               No.

Female:                               No, never a person.

Female:                               No.

Josh Greene:                    Instead of having one system that just churns out the answer and bing, we have multiple systems that give different answers, and they duke it out, and hopefully out of that competition comes morality.

Robert Krulwich:             This is not a trivial discovery that you struggle to find right and wrong depending upon what part of your brain is shouting the loudest. It's like bleachers morality.

Jad Abumrad:                   Do you buy this?

Robert Krulwich:             I just don't know. I've always suspected that a sense of right and wrong is mostly stuff that you get from your mom and your dad and from experience, that it's culturally learned for the most part. Josh is a radical in this respect. He thinks is biological. Deeply biological. Somehow we inherit from the deep past a sense of right and wrong that's already in our brains from the get-go, before mom and dad.

Josh Greene:                    Our primate ancestors, before we were full-blown humans, had intensely social lives. They have social mechanisms that prevent them from doing all the nasty things that they might otherwise be interested in doing. Deep in our brain we have what you might call basic primate morality. Basic primate morality doesn't understand things like tax evasion, but it does understand things like pushing your buddy off of a cliff.

Robert Krulwich:             You're thinking then that the man on the bridge, that I'm on the bridge next to the large man, and that I have hundreds of thousands of years of training in my brain that says, "Don't murder the large man." Even if I'm thinking, if I murder the large man, I'm going to save five lives and only kill the one man, but there's something deeper down that says, "Don't murder the large man."

Josh Greene:                    That case, I think it's a pretty easy case. Even though it's five versus one, in that case people just go with what we might call the inner chimp.

Robert Krulwich:             The inner chimp is an unfortunate way of describing an act of deep goodness.

Josh Greene:                    That's what's interesting.

Robert Krulwich:             10 Commandments for ... Inner chimp.

Josh Greene:                    What's interesting is that we think of basic human morality as being handed down from on high, and it's probably better to say that it was handed up from below, that our most basic core moral values are not the things that we humans have invented, but the things that we've actually inherited from other people. The stuff that we have humans have invented are the things that seem more peripheral and variable.

Robert Krulwich:             Something as basic as thou shalt not kill, which many people think was handed down in tablet form from a mountaintop, from God directly to humans, no chimps involved, you're suggesting that hundreds of thousands of years of on-the-ground training have gotten our brains to think, "Don't kill your kin."

Josh Greene:                    Right, or at least that should be your default response. Certainly chimpanzees are extremely violent and they do kill each other, but they don't do it as a matter of course. They, so to speak, have to have some context-sensitive reason for doing so.

Robert Krulwich:             Now we're getting to the rub of it. You think that profound moral positions may be somehow embedded in brain chemistry?

Josh Greene:                    Yeah.

Jad Abumrad:                   That's a cool idea though, that when you have these gut feelings, and we talk about our gut, "I know in my gut this is right or this is wrong," really in that moment that's evolution talking.

Robert Krulwich:             Yeah, he calls it our inner chimp.

Jad Abumrad:                   That phrase bothers you?

Robert Krulwich:             Yeah.

Frans de Waal:               Inner chimp, that's an interesting way.

Jad Abumrad:                   You'll be glad to know it was a phrase that was not too familiar to a guy who specializes in chimps.

Frans de Waal:               My name is Frans de Waal, and I am a professor at Emory University. I also work at the Yerkes Primate Center in Atlanta, Georgia. We'll see, maybe they make some noise without food.

Jad Abumrad:                   Frans de Waal, he knows chimps, he's observed chimps, in some cases the same chimps, for the last three decades. Though he doesn't use the phrase inner chimp, he would agree that human morality is not special. All you have to do is watch chimps do their thing for five minutes to see that, which we did. He took us on a little walk around his office.

Frans de Waal:               115 acres of land here in the middle of Atlanta with 2,000 primates.

Jad Abumrad:                   Some bonobos, gorillas.

Frans de Waal:               Mostly monkeys.

Jad Abumrad:                   He keeps his chimps in big stadium-type enclosures. They're like gladiator rings with high walls and no roof. Off to one side there's an observation tower. On the way to one of these big things, we had to pass through some woods, and we crossed a blackberry bush, at which point Frans stopped.

Frans de Waal:               I'm going to cut a few branches of blackberry. They like blackberry a lot.

Jad Abumrad:                   This is him cutting the branches.

Frans de Waal:               They love the young shoots. You will see. Pull this one out. Not bad at all.

Jad Abumrad:                   Anyhow, a few minutes later we climbed the ladder to the observation tower so we could see the chimps down below. 15 chimps were milling around in the heat, and then ...

Frans de Waal:               All right, guys.

Jad Abumrad:                   ... this is a cool part, with big smile on his face, Frans drops the branch into the enclosure.

Frans de Waal:               Oops.

Jad Abumrad:                   There it goes. Lands 20 feet below, right in front of a female.

Frans de Waal:               That's a young female, Katie, who takes it. She has the enormous branches of blackberry. There's one female coming over. They're not going to be happy to share. See, there's a fight.

Jad Abumrad:                   There's a fight, but do you hear how it stops like that on a dime?

Robert Krulwich:             Look, didn't you edit the tape?

Jad Abumrad:                   No, I didn't.

Robert Krulwich:             Really, it stopped like that?

Jad Abumrad:                   Unedited tape. Raw tape.

Robert Krulwich:             What happened? What happened?

Jad Abumrad:                   What happened was that the alpha male, number one chimp, comes out, and then everyone shuts up.

Frans de Waal:               The alpha male is coming over. He is here.

Jad Abumrad:                   Then after him comes number two.

Frans de Waal:               Now the second male has taken the food.

Jad Abumrad:                   Then the two of them stand together for a while. Who knows what they're doing? Eventually number two takes the branch and walks toward the back of the enclosure.

Frans de Waal:               You see he's being followed by females.

Jad Abumrad:                   At the back of the enclosure is a hut, a little building. One by one, all 15 chimps file in after him.

Frans de Waal:               Now they're going in the building with the branch, which is bad for us, because we may not hear a lot.

Robert Krulwich:             Can we see what they're doing?

Jad Abumrad:                   Mm-mm (negative). Unfortunately not. There's no need to wonder, because Frans told us what they were doing. He's seen it a million times. This is how they share.

Frans de Waal:               They will probably divide the thing and then some individuals will have a large branch and then they will start sharing with the rest.

Robert Krulwich:             Wow.

Jad Abumrad:                   See, they have the system. Anytime some food lands in the enclosure and the juveniles get it and they can't decide who gets what, the adults will take it, lead everyone into the hut, where they will divide the branch into pieces.

Frans de Waal:               Usually in the end everybody gets something. We have this wonderful word. If we do something nice we call it humane behavior, meaning that we borrow from our species name to describe it, but it's actually a very ancient tendency.

Jad Abumrad:                   Ancient, Frans says, because the only way our primate ancestors made it this far was through cooperation.

Frans de Waal:               That's the key. Of course if you fall and stumble and bleed and are in trouble, I should respond to that, because my survival also depends on how you are doing. That doesn't mean that there's no nastiness.

Jad Abumrad:                   Chimps do fight. They do kill each other, but on the whole, they get along. They've gotten along for so long that evolution, he says, has etched some really basic instincts into our brains, sharing, reciprocity, and the most basic one of all.

Frans de Waal:               If you were remain the capacity for empathy ...

Jad Abumrad:                   Empathy.

Frans de Waal:               ... for morality the whole thing falls apart. Then it just becomes a bunch of rules.

Jad Abumrad:                   People disagree about this, what's the real essence of morality. Is it thoughts, is it feelings? Frans says it's empathy.

Frans de Waal:               You can see very striking instances of empathy in the apes.

Jad Abumrad:                   He literally has a hundred different examples, but here's a really good one that you may remember.

Frans de Waal:               There's this famous case in the Brookfield Zoo where a gorilla rescued a boy who had fallen into the enclosure. This happened 10 years ago.

Newscaster:                     It was a parent's nightmare. A three-year-old boy had climbed over a railing and fallen 18 feet into the gorilla pit.

Robert Krulwich:             What did the gorilla in that case do?

Frans de Waal:               She went over to pick up the boy.

Newscaster:                     As he lay injured and unconscious on the concrete, Binti gently scooped him up.

Frans de Waal:               She sat down with the boy. She patted him on the back and she seemed to calm him down.

Newscaster:                     Then she did something amazing.

Male:                                     She carried him probably about 50 or 60 feet.

Frans de Waal:               Then she brought him to a place where people could get to him.

Newscaster:                     Paramedics quickly removed the boy from the pit.

Frans de Waal:               All of this was videotaped because there were people there videotaping it.

Male:                                     Just incredible.

Child:                                     I never thought a gorilla would do that.

Frans de Waal:               A big deal was made of it in the media, but actually the response of that gorilla to the boy who had fallen in was a very common, typical ape response.

Jad Abumrad:                   There you go.

Robert Krulwich:             Look, I'll concede the point that when Mount Sinai happened, that wasn't the beginning of creatures learning to do good or knowing the difference between good and bad. I will say that I still think there's a difference between human beings and apes and monkeys. It's a tangible difference. Let me do one more story. This is a Josh Greene story. I don't think you could handle this one if you were a monkey. It's even hard to handle if you're a human.

Josh Greene:                    The situation is somewhat similar to the last episode of MASH, for people who are familiar with that. The way we tell the story, it goes like this. It's wartime.

Male:                                     There's an enemy patrol coming down the road.

Josh Greene:                    You are hiding in the basement with some of your fellow villagers.

Male:                                     Let's kill those lights.

Josh Greene:                    The enemy soldiers are outside. They have orders to kill anyone that they find.

Male:                                     Quiet! Nobody make a sound until they've passed us.

Robert Krulwich:             There you are, you're huddled in the basement. All around you are enemy troops, and you're holding your baby in your arms. Your baby with a cold, a bit of a sniffle. You know that your baby could cough at any moment.

Josh Greene:                    If they hear your baby, they're going to find you and the baby and everyone else and they're going to kill everybody. The only way you can stop this from happening is cover the baby's mouth, but if you do that, the baby's going to smother and die. If you don't cover the baby's mouth, the soldiers are going to find everybody and everybody's going to be killed, including you, including your baby.

Robert Krulwich:             You have the choice. Would you smother your own baby to save the village or would you let your baby cough, knowing the consequences?

Josh Greene:                    This is a very tough question. People take a long time to think about it. Some people say yes and some people say no.

Female:                               Children are a blessing and a gift from God, and we do not do that to children.

Female:                               Yes, I think I would kill my baby to save everyone else and myself.

Male:                                     No, I would not kill the baby.

Female:                               I feel because it's my baby, I have the right to terminate the life.

Male:                                     I'd like to say that I would kill the baby, but I don't know if I'd have the inner strength.

Male:                                     No. If it comes down to killing my own child, my own daughter or my own son, then I'd choose death.

Male:                                     Yeah, if you have to. Of course it was done in World War II. When the Germans were coming around, there was a mother that had a baby that was crying, and rather than be found, she actually suffocated the baby, but the other people lived.

Female:                               Sounds like an old MASH thing. No, you do not kill your baby.

Robert Krulwich:             In the final MASH episode, the Korean woman who's a character in this piece, she murders her baby.

Male:                                     She killed it! She killed it! Oh my god! Oh my god! I didn't mean for her to kill it! I just wanted it to be quiet! It was a baby! She smothered her own baby!

Robert Krulwich:             What Josh did is he asked people the question, would you murder your own child, while they were in the brain scanner. At just the moment when they were trying to decide what they would do, he took pictures of their brains. What he saw, the contest we described before was global in the brain. It was like a world war. That gang of accountants, that part of the brain was busy calculating, calculating, a whole village could die, a whole village could die, but the older and deeper reflex also was lit up, shouting, "Don't kill the baby! No, no, don't kill the baby!"

Male:                                     No!

Robert Krulwich:             Inside the brain was literally divided.

Male:                                     Do the calculations.

Male:                                     Don't kill the baby.

Male:                                     Do the calculations.

Male:                                     Don't.

Robert Krulwich:             Two different tribes in the brain literally tried to shout each other out. Jad, this was a different kind of contest than the ones we talked about before. Remember before when people were pushing the man off of the bridge, overwhelmingly their brains yelled, "No, no, don't push the man!" When people were pulling the level, overwhelmingly, "Yeah, yeah, pull the lever." There it was distinct. Here I don't think really anybody wins.

Jad Abumrad:                   Who breaks the tie? They had to answer something, right?

Robert Krulwich:             That's a good question. What happens? Is it just two cries that fight each other out, or is there a judge?

Josh Greene:                    That's an interesting question. That's one of the things that we're looking at.

Robert Krulwich:             When you are in this moment with parts of your brain contesting, there are two brain regions.

Josh Greene:                    These two areas here towards the front.

Robert Krulwich:             Right behind your eyebrows, left and right, that light up. This is particular to us. He showed me a slide.

Josh Greene:                    It's those areas that are very highly developed in humans as compared to other species.

Robert Krulwich:             When we have a problem that we need to deliberate over, the front of the brain, this is above my eyebrow?

Josh Greene:                    Yeah, right about there.

Robert Krulwich:             There's two of them, one on the left and one on the right.

Josh Greene:                    Bilateral.

Robert Krulwich:             They are the things that monkeys don't have as much of that we have?

Josh Greene:                    Certainly these parts of the brain are more highly developed in humans.

Robert Krulwich:             Looking at these two flashes of light at the front of a human brain, you could say we are looking at what makes us special.

Josh Greene:                    That's a fair statement.

Robert Krulwich:             A human being wrestling with a problem, that's what that is.

Josh Greene:                    Yeah, where it's both emotional, but there's also a rational attempt to sort through those emotions. Those are the cases that are showing more activity in that area.

Jad Abumrad:                   In those cases when these dots above our eyebrows become active, what are they doing?

Robert Krulwich:             He doesn't know for sure, but what he found is in these close contests, whenever those nodes are very, very active, it appears that the calculating section of the brain gets a bit of a boost, and the visceral, inner chimp section of the brain is muffled.

Male:                                     No! No! No!

Robert Krulwich:             The people who chose to kill their children, who made what is essentially a logical decision, over and over, those subjects had brighter glows in these two areas and longer glows in these two areas. There is a definite association between these two dots above the eyebrow and the power of the logical brain over the inner chimp or the visceral brain.

Josh Greene:                    That's the hypothesis. It's going to take a lot more research to tease apart what these different parts of the brain are doing or if some of these are just activated in an incidental kind of way. We really don't know. This is all very new.

Jad Abumrad:                   How many people chose to kill their baby?

Robert Krulwich:             About half.

Jad Abumrad:                   Wow, that's not bad.

Robert Krulwich:             What do you mean it's not bad? You're in favor of killing the baby?

Jad Abumrad:                   What would you do?

Robert Krulwich:             Me? I must have a very noisy chimp, because it wouldn't even consider-

Jad Abumrad:                   I would kill the baby.

Robert Krulwich:             You would?

Jad Abumrad:                   The village will go on to have a hundred babies. Your baby is just one.

Robert Krulwich:             My baby is my world. My baby is my universe.

Jad Abumrad:                   You're going to erase all those people based on your one child?

Robert Krulwich:             First of all, we all need you to know that Jad Abumrad does not have a child of his own yet.

Jad Abumrad:                   True.

Robert Krulwich:             What you can't know is you can't know what it would be like to look into your own daughter's face, your own son's face, and end that life.

Jad Abumrad:                   Yeah, you're right.

Robert Krulwich:             I know you. You couldn't do that.

Jad Abumrad:                   Agreed, I don't know what I would do really, but if you're just asking me right now in the abstract which is more right, I couldn't live with myself if I didn't act on behalf of the greater good.

Robert Krulwich:             Look, you know what I think? I think the real essence of a moral sense, if we want to bring this discussion to its real end, you say what is it about human beings that the animals still don't have and me never hope and I hope we'll never have, guilt.

Jad Abumrad:                   Guilt?

Robert Krulwich:             Yeah, guilt. The ability to blush.

Frans de Waal:               That's the one expression that the apes don't have, as far as I know, shame and guilt. I'm not sure that they are particular well developed in the chimpanzee.

Jad Abumrad:                   Wow, so shame. We should embrace our shame, which is good, because I actually spend most of my life feeling ashamed.

Robert Krulwich:             In that we're exactly the same.

Jad Abumrad:                   For more information on neuroscientist and philosopher Josh Greene and primatologist Frans de Waal, who you just heard, visit our website,

Female:                               You're listening to Radiolab.

Male:                                     Radiolab.

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Male:                                     WNYC.

Female:                               NPR.

pat walters:                      Hey everybody, Pat Walters here. I'm a producer at Radiolab. I'm here because I need your help. This summer I'm hosting a series of stories on the show. I have requests for those of you who spend a lot of time with kids, parents, aunts and uncles, teachers. We're looking for stories about what we're calling tiny moments of childhood brilliance. Basically I want to hear about those times when a kid you know did something that just made you lean back and say, "Whoa, how did they do that?" Maybe it was the moment that a kid you'd been reading to for months started reading back to you, or maybe the kid was at piano lessons and you suddenly noticed they were doing advanced math on the margin of their musical score, or maybe the kid was in math class and you noticed they were writing music in the margin of their geometry homework. We're interested in those small, specific moments where a kid does something super smart, but it doesn't have anything to do with a test. If you have a story, please share it with us. You can go to and record a short audio message for us. Again, that's Thank you so much.

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Jad Abumrad:                   This is Radiolab. I'm Jad Abumrad.

Robert Krulwich:             I'm Robert Krulwich.

Jad Abumrad:                   Today on our program, the science of morality, of right and wrong and good and bad.

Robert Krulwich:             If we have now at least an argument in our heads about where moral sense might lie in the brain, now let's ask when does it get turned on, when do you think that humans begin to get a sense of right and wrong.

Jad Abumrad:                   I actually asked that question to an expert.

Judy Smetana:                My name is Judy Smetana.

Jad Abumrad:                   Judy Smetana is her name.

Judy Smetana:                I'm a professor at the University of Rochester. Kids clearly know more than they can say. It's clear from both observations and anecdotes that children really are beginning to develop a moral sense in the second year of life. Of course that experience increases as they move into the threes, but they're also beginning to form a much more complex or developed understanding of moral rules, which they can share with us a little bit in our interviews.

Male:                                     Who makes the rules at your school?

Child:                                     My teachers.

Jad Abumrad:                   When you do the interviews with kids directly, what kind of questions are you asking them?

Male:                                     Can they change the rules if they want to?

Child:                                     They're the teachers. They can do whatever they want.

Judy Smetana:                We try to ask them really some very complex ideas in a simple form.

Male:                                     Is there a rule about hitting at your school?

Child:                                     Yes.

Judy Smetana:                Such as would it be okay to hit if your teacher didn't see you or would it be okay to hit if there was no rule about it in your school.

Male:                                     Suppose the teachers at school agree that they won't have any rule about hitting at school, there's no rule anymore. Then would it be okay for a boy to hit another kid hard?

Child:                                     No.

Male:                                     No? How come?

Child:                                     Because that would make somebody feel bad.

Male:                                     It would. What's wrong with hitting somebody anyway?

Child:                                     It's made out of the skin, because their skin can get cut or get a bruise.

Judy Smetana:                What we found is that young children, beginning at about three, but really much more reliably by age four, will say that things like hitting or hurting or teasing would be wrong, even if the teacher didn't see them or didn't have a rule, whereas other things like sitting in the circle in circle time ...

Male:                                     Is there a rule at your school about sitting down while you eat your lunch?

Child:                                     Yes.

Judy Smetana:                ... would be okay if there was no rule about it.

Male:                                     Is that a rule the teacher could change?

Child:                                     Yes, if she says, "Okay, you could stand up," you could do that. You have to listen to the teacher.

Judy Smetana:                It's clear that the moral universe begins very early for young children.

Female:                               Hello.

Female:                               Fay, who's hosting today, got this idea to start a play group.

Female:                               All of our kids are out in the living room playing together as they usually do, trying not to kill each other.

Female:                               I'm finding the threes a little bit easier on Dana than the twos because my son has no fear. We call him the red tornado.

Female:                               Hey there, what's your name?

Alex:                                       Alex.

Female:                               Once he turned three ...

Female:                               Hold old are you?

Alex:                                       Three.

Female:                               I find that we're able to explain things to him easier.

Jad Abumrad:                   What kind of things, like rules?

Female:                               Rules, oh yeah. Rules.

Female:                               Can you tell me what the rules are? You're nodding yes.

Female:                               If you ask him the rules of the house, he says no hitting, no pushing, no banging heads.

Alex:                                       No hitting, no pushing, no banging heads.

Female:                               Those are the rules. He knows.

Female:                               No pushing, no hitting, and what's the other one?

Alex:                                       No banging heads.

Female:                               No banging heads.

Female:                               Doesn't always follow them though. Alex, do it gentle.

Judy Smetana:                One of the things that we see is that young children can tell you that things are wrong, that it's wrong to hit because it hurts, wrong to take toys. At the same time, kids do take other kids' toys, they do hit each other. You have to wonder, why is it if they know it's wrong, why are they doing this.

Jad Abumrad:                   Because it feels good, right?

Judy Smetana:                Yeah, it feels good, because they got what they wanted. Some researchers have called that the happy victimizer effect.

Jad Abumrad:                   To hit another kid or to take another kid's toys feels good, but to have your toys taken by another kid feels bad. Is that the basic information that a child uses to start forming their moral universe?

Judy Smetana:                Right. The task of a young child's development is to be able to coordinate those two perspectives, that of the victim and that of the transgressor, and weight it toward the way that the victim feels.

Jad Abumrad:                   What we're really talking about is a happy victimizer versus empathy.

Judy Smetana:                Yeah.

Gavin:                                   Hello.

Male:                                     I would say that the absence of empathy is one of the characteristics of really young kids.

Gavin:                                   What's this?

Jad Abumrad:                   It's a microphone.

Gavin:                                   My name is Gavin.

Male:                                     Gavin, make sure you don't have any yogurt on your fingers.

Gavin:                                   I am two years old.

Male:                                     You say to them, "Do you see how you don't like being teased, but then you teased your brother and see how it made him feel," you might as well be speaking in Farsi to them. They're a little bit like sociopaths.

Jad Abumrad:                   Do you think that's overstating it?

Female:                               I think so. I guess in a very general way that's true, but I think we're born with some very rudimentary sense of empathy hardwired in. People are very persuaded, for instance, by the primate evidence, that that's something that you see in other species.

Female:                               I do think that kids are born with different innate levels of empathy. I happened to be going to school early one day. I'm never early. They have an observation closet where you can watch the classroom. I'd not ever observed, because I'm never early, so I went into the closet. At that moment I saw Jack tackle his best friend, drop behind a bookcase, the rest of the classroom gather round. Then I saw Jack stand up and just look down with this very startled, frightened look on his face. Then I saw his friend stand up with his lip bleeding. I thought, "I can't believe I'm watching this happen." The only time I've ever watched my son through the window at school, and I think he just gave someone a bloody lip. He was mortified by the whole thing. He was mortified, I think scared about his own actions. In some ways, I said to my sister, at that moment I regretted that I didn't run in the classroom. My sister said, "The best thing you did was stay out of it."

Jack:                                       Jack, and I'm four.

Female:                               Jack had to see the consequences of his own actions on his own terms.

Jack:                                       (sings)

Male:                                     I love that song.

Jad Abumrad:                   I love that song too. Thank you, Jack, and also Jack's parents, William and Tori [Brangam 00:37:42]. Thanks also to Dana, Missy, Ana, and Fay for letting us eavesdrop on their playgroup. Thanks also to our experts, Judy Smetana, professor of psychology at the University of Rochester, and to the Larry Nucci, professor at the University of Illinois in Chicago.

Robert Krulwich:             If this moral sense gets turned on when you're three or four, there are some moments in your life where you get so embarrassed by something that you did that your moral sense never turns off. That's the next story.

Jad Abumrad:                   It comes from producer Amy O'Leary. For her that moment came in the 4th grade, during a game her class played called Homestead, a cross between Dungeons and Dragons and Monopoly. It was supposed to teach kids about pioneer history. Amy felt so bad about how she acted in this game that many years later she wrote her teacher a letter, and he never responded, so she went to see him.

Amy O'Leary:                    Where's your classroom?

Mr. Riggs:                            Down this way.

Amy O'Leary:                    The kids are off in?

Mr. Riggs:                            PE.

Amy O'Leary:                    As we walk through the hallway, I realize why I'm feeling so disoriented. I'm a grownup with a 401k, and the doorknobs in the school come up to my knees. When we sit down for the interview part of the interview where I'm supposed to ask Mr. Riggs about this game we played, frankly all I could think of was the most obvious question. How are you?

Mr. Riggs:                            Older, balder, grayer, fatter. Still teaching, probably have still six or seven years left to go.

Amy O'Leary:                    How many-

Mr. Riggs:                            34.

Amy O'Leary:                    34 years.

Mr. Riggs:                            Yeah, I've been teaching probably longer than half the staff's been alive.

Amy O'Leary:                    You still play Homestead?

Mr. Riggs:                            Yes, we're still trying to do it.

Amy O'Leary:                    You just grabbed your forehead and had this look of anguish. What was that for?

Mr. Riggs:                            This class, this has been a difficult class. Some of them will do it. Some of them won't. Some of them will remember it. You remembered it. Did everyone in the class remember it?

Amy O'Leary:                    I already knew the answer to that, because I'd checked.

Jeff:                                         Hello?

Amy O'Leary:                    I found Jeff in L.A. Jeff, do you remember Homestead?

Jeff:                                         Vaguely.

Amy O'Leary:                    Dale in Phoenix. Dale, do you remember the Homestead game that we played?

Dale:                                      Vaguely.

Amy O'Leary:                    [Steffa 00:40:12], who I met at a bar in Brooklyn where she works. Do you remember Homestead, the game?

Steffa:                                   No, not as much as you do, obviously. Once you start talking about it, I may remember it.

Amy O'Leary:                    It was this simulation game that we were supposed to be prairie settlers. There was this big plywood map at the front of the classroom. We had these little booklets that were black-and-white booklets.

Mr. Riggs:                            These are the booklets you used.

Amy O'Leary:                    Wow. Standing in this classroom, I remember everything about the game. I hold this and I have a flood of memories. I remember the power and the slum-lording, the price gauging. I think the purpose of the game was to teach us something about the history of the kinds of people who had to settle the West. You were assigned a character and a plot of land. Every day you played it, each individual student would have a different fortune. You might roll a one and there'd be a drought and you wouldn't get any money off of your land, or you'd roll a six and that meant that there was a bumper crop. It was a lot like a Monopoly game.

Mr. Riggs:                            With that in mind, I've got the board there.

Amy O'Leary:                    Is that the same board?

Mr. Riggs:                            Yeah, it's the same board.

Amy O'Leary:                    Let's look at it. I remember this. Just as luck would have it, one of the very first things that happened in the game is that Mr. Riggs announced that this land, the square in the middle there, land square 18, my land, that's the piece of land that I had, would be the center of town.

Mr. Riggs:                            You got to sell all the town property and everything and run the town.

Jad Abumrad:                   What did you think of this?

Amy O'Leary:                    I knew at the time it would help me win the game. I thought, "This is lucky. I have something that nobody else has." I thought it was further evidence that I was special. I was always a good student. I thought this is what good students, you get rewarded with lucky things.

Jad Abumrad:                   Then what'd you do?

Amy O'Leary:                    I started by forming a company. We'd go to a kid. We'd say, "Hey, do you want to join our company?" They'd be like, "What's that?" We'd say, "We're going to be a company and we're going to be all together. You give us your land and we'll give you a place in the town to live. Everybody wants to move to the town. Don't you want to be in the town? Meanwhile, I'll take all the profits from your farmland." You could get 200 to 1,000 a year on your crops on your land, and then we would pay them $50 a year. It was a simulation game, so nobody actually had to go out and work their fields to reap the profits off the land, but these people basically sold themselves into a very low wage slavery situation.

Jad Abumrad:                   All the other nine-year-olds went for this?

Amy O'Leary:                    Yes.

Jad Abumrad:                   Why?

Amy O'Leary:                    Peer pressure. They thought we were the cool kids. They would all say yes. That's what I remember is almost no one turned us down. Once you've got 20 kids who are part of the company, oh my god, I can do whatever I want. Crazy total power. Anything. Any bullying tactic. There were things that would come up like the booklet would say your family's having a medical problem, you need to pay the doctor. My baby's sick, my baby's sick! The doctor worked for our company, and the doctor would overcharge the people who were not in the company. If you were not part of the company, it was going to cost you a lot of money. More money than any of these people had.

Jad Abumrad:                   Sheesh.

Amy O'Leary:                    That wasn't even the worst of it.

Dale:                                      I do somewhat remember that whole episode of ...

Amy O'Leary:                    That's Dale again.

Dale:                                      ... us having to actually stop the game early.

Amy O'Leary:                    He didn't remember much, but he remembered the money. It's hard to forget the money.

Dale:                                      You had flooded the whole game with counterfeit money, and everybody else's wasn't worth anything anymore.

Amy O'Leary:                    The game used Monopoly money to begin with. Once we got big enough where we realized nobody could really track our finances, we just started bringing it in from home. We actually brought in Life money and Monopoly money from home and flooded the classroom currency market. It was an absurd amount of money. In hindsight I've thought that you had to notice that.

Mr. Riggs:                            It was noticeable, because I was stamping the money with a Groucho Marx stamp I had on the back, and that was the real stuff, and anything without the Groucho was the counterfeit. No class has taken it as far as you guys is.

Jad Abumrad:                   Did Mr. Riggs ever tell you this was wrong?

Amy O'Leary:                    No, never. He never said it explicitly. He just one day called this meeting. I remember this meeting very clearly. You brought us all up to the front of the room. Six kids, frustrated, gathered around one side of Mr. Riggs's big teacher's desk. I stood on the other. You said, "We don't exactly think this is fair," but you didn't tell us it was wrong or that you're cheating or you're counterfeiting money and I know it. What I remember was that you raised the question. He asked me, "What are you going to do about this?" A long pause. He wasn't punishing me or saying it was against the rules exactly. I couldn't figure out what was going on. We were winning. What was I going to do about it? "Nothing," I told him. That's when he gave me this look. It was almost like there was a quiet disappointment that you had. All the hope he'd had for me as a human being just slid right off his face.

Mr. Riggs:                            Did that help develop a conscience in you? Has that ever come back so that you think about things differently?

Amy O'Leary:                    Utterly. That's exactly why I've remembered this for so long and so well. It stuck with me as this lesson of, even if you're not going to get punished for something, it still can be wrong.

Mr. Riggs:                            Then it was successful if that has happened.

Amy O'Leary:                    Do you do that on purpose?

Mr. Riggs:                            I think I did it on purpose then, because it was one of those teachable moments that happens and you just revel in it, how wonderful it is that this was presented.

Amy O'Leary:                    My classmate Dale put things into perspective.

Dale:                                      Everybody does things when they're that age that make you feel bad to learn what's right or wrong.

Amy O'Leary:                    Do you have things like that? What he told me next caught me off guard.

Dale:                                      Yeah. Travis Sherman was a friend of mine that lived in the neighborhood, and we were the best of friends, riding our bikes around town. We were coming home, crossing a freeway off-ramp. I was in front of Travis. I made it across. The next thing I remember hearing is just squealing tires, and I look around, and Travis is half underneath this car out in the intersection. I remember him half standing up, and his leg was folded up like origami almost, just trashed. He just looked up at me and said, "Oh god, Dale, my leg," and he fell back down. I couldn't have been more than six, but for whatever reason, I didn't go back to him. I just turned around and I got on my bike and I just rode off. I don't even think I told my mom about it. He tried calling from the hospital several times, and I just remember going, "No, I don't want to talk to him. I don't want to talk to him." My mom finally says, "No, you're going to talk to him, whether you like it or not." When I finally did get on the phone, I just clearly remember him asking, "Why did you do that? How come you didn't come back for me?" I didn't have an answer for him.

Dale:                                      To this day it's one of those things that still bugs me about myself. Even though I was only that old, that still bothers me that I would do that, that I would turn around and leave somebody who needs help like that. Maybe that factors into how I am as a person today. I'll help anybody I can, just because I don't want to have that feeling again.

Amy O'Leary:                    I asked Dale if he could erase that day from his life, would he? "No," he said, "Not in a million years." It's part of who he is now. Who he is now is the kind of guy who will come and pick you up in the middle of the desert when your car breaks down at 3:00 a.m., no questions asked. He's a really loyal friend, a good person. I didn't go back to see Mr. Riggs to resolve anything. I didn't need him to say that deep down he always thought he was a good kid or that he's no longer disappointed in me. What matters is that once he was disappointed in me. I think about that all the time. Do you find that with kids this age, that that particular lesson is one that they're sorting through right now that kids who are eight, nine years old?

Mr. Riggs:                            Yeah, they're sorting through that. Is there a right, is there a wrong, what is morality? Usually there's a sense of fairness. These kids have got fairness down to the nth degree. They can look at one of these cupcakes and tell you to the ounce which one's bigger, and if somebody else gets it, it's not fair and everything else. Is that morality? I think if people are left alone that they have a tendency to do the right thing. Kids have the tendency to do the right thing. There are several kids that I don't think will ever have a grasp of that, and whether it's genetics or very early family background.

Amy O'Leary:                    How can you tell that so early?

Mr. Riggs:                            When you see a child that consistently pokes, consistently cuts, cheats, steals, lies, whatever, and I'm saying at three, at four, at five, not just in third grade, I think that child's cursed, doomed, whatever, for the rest of their lives.

Amy O'Leary:                    I spend the rest of the day with Mr. Riggs's class, thinking about what he said, watching his third-graders.

Child:                                     Why don't you just go [inaudible 00:50:37]?

Amy O'Leary:                    I asked [Athan 00:50:40], a kid in the front row, what the rules are. Could you tell me what the rules are in this room?

Athan:                                   You got three of them right up there.

Amy O'Leary:                    He points to a poster, and I remember that too.

Athan:                                   Act safely, respect others and their property.

Amy O'Leary:                    At the top, rule number one.

Athan:                                   Do what you know is right.

Amy O'Leary:                    Do what you know is right. Those work pretty well?

Athan:                                   Yeah, they actually sometimes do.

Jad Abumrad:                   Thanks, Amy O'Leary, for producing that story. One more story like it coming up on Radiolab. Stay with us.

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Jad Abumrad:                   This is Radiolab. I'm Jad Abumrad.

Robert Krulwich:             I'm Robert Krulwich.

Jad Abumrad:                   This hour we've been looking at morality, good and bad, right and wrong.

Robert Krulwich:             Now let us say that you are wrong, you have done something bad, and that the society around you says you're guilty. If you go back 250 years, the city fathers of Philadelphia have an interesting way to make its citizens own up to their guilt.

Jad Abumrad:                   It is a giant gothic castle that still sits today in the middle of downtown Philadelphia, except it's no longer occupied and it's falling apart. We sent producer Josh Braun to take a look.

Sean Kelley:                      Do you want to just walk over and look around a little bit?

Josh Braun:                       Can we look around a little bit and just get some ambiance and stuff like that?

Sean Kelley:                      Yeah, you bet. The building is truly ruined. There used to be two huge oak doors here, and they had iron studs all ... This building is based on a profoundly optimistic view of human nature. Imagine swinging this giant door open. That all people are inherently good. You being our new inmate, first thing would be to have your head covered with a hood. That every human being in their heart had an instinct to behave right, to do the right thing, so they argued for a prison that would house every man and every woman in a profound isolation. They thought that isolation would encourage spiritual reflection and the prisoners would become penitent. This was the world's first true penitentiary, a building designed to make someone penitent, genuinely sorry for what they did.

Sean Kelley:                      We're going to walk down here. They called this the south corridor, this big arched corridor here. Quaker prison reformers argued that inmates should be totally cut off from the outside world. They didn't allow them to get letters from home. They didn't allow them any books, aside from a copy of the King James Bible. They were looking for near total sensory deprivation. They wanted you to see the four white walls of your 8x12 cell and not a whole lot else, for years.

Sean Kelley:                      Here you are inside of your cell. You can see it has a cot in it with a simple mattress stuffed with straw. Those over there are tools for making shoes. The cell, what always amazes me every time is how high the ceiling is. 16' vaulted ceilings. It's got this beautiful arch to it. Then they have that skylight. They called them the eye of God. Daylight that came down through this circular opening is supposed to mimic the look of an eye looking down at you. You're supposed to be going through a profound spiritual reflection while you're here, and so they wanted all the light to come down from above. On a gray day like this, you really get a sense for how gloomy the cell would've been. You stay here for one second, I'll be right back. I'll see you in a few minutes.

Sean Kelley:                      We have a letter from an inmate. He wrote to his mother saying, "I've just received word that I will serve my sentence in the Eastern State Penitentiary in silence and incredible crushing isolation. Please endeavor to secure for me a pardon."

Sean Kelley:                      The people who ran this prison were fascinated by silence. They just fetishized the idea of total silence. They wanted the inmates' life back here in these cells to be almost completely silent. As they walked up and down the corridors, the guards would put socks over there shoes so that you wouldn't hear the footsteps. As they rolled carts of food to deliver meals here in the cells, they covered the wheels of the cart with leather so they would roll in silence.

Sean Kelley:                      A friend of my mother's was telling me about his time in the Peace Corps. He was in Gabon, Africa. He was in the jungle. He said the jungle was so dense, they would only carve out chunks of jungle big enough for the exact spaces that they needed, for little gathering spots for their houses. If they'd left something for a couple of weeks, it'd be just jungle again. After two years of being in this village, he went off to visit a friend in Kenya and went out to the plains, and he said his eyes physically couldn't focus on distances further than about 10 feet out, because they hadn't done it in two years. He said the entire time when he was out there, he felt exposed, like there was things behind him that he couldn't see.

Sean Kelley:                      All I could think about was Eastern State Penitentiary and being in these little cells about 8x12 for years. Then you walk out, and the first thing you see is the prison itself extending 680 feet in either direction. Must've freaked people out.

Sean Kelley:                      There was this growing debate that prolonged isolation could cause insanity, that it could cause emotional breakdown. What looked to be optimistic in the 1830s looked pretty cynical by the 1860s. By about the building's hundredth birthday, they had given up the idea of solitary confinement and they were holding inmates here for life sentences. The walls were built with the idea that people are inherently good, and by the end they were housing all these inmates who apparently they had assumed were inherently evil. We'll lock up behind us. These days our major security concern is people getting in, vandals, all that kind of stuff.

Jad Abumrad:                   Josh Braun produced that audio tour with recording help from Sally Herships. The voice you heard was Sean Kelley. For more information on Eastern State Penitentiary or the science of morality or anything that you heard this hour, visit our website. What's the address?

Robert Krulwich:             The address is ...

Jad Abumrad:                   Come on, you should have it memorized by now.

Robert Krulwich:   

Jad Abumrad:          While you're there, let us know what you think. Our email address is I'm Jad Abumrad.

Robert Krulwich:             I'm Robert Krulwich.

Jad Abumrad:                   We are signing off.

Dale Keyes:                       Radiolab is produced by Jad Abumrad and Ellen Horne, with help from Sarah Pellegrini, Melissa [Kebble 00:58:41], Amber [Sealy 00:58:42], and [Sarissa 00:58:42] Tanner. Special thanks to David Martin and the Vanderbilt Television News Archive, and to me, Dale Keyes. Radiolab is produced by New York Public Radio, WNYC, and distributed by NPR.

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