(SOUNDBITE OF ARCHIVED RECORDING)HUGH HARRIS: T-minus 15 seconds.SHANKAR VEDANTAM, HOST: This is HIDDEN BRAIN. I'm Shankar Vedantam.(SOUNDBITE OF ARCHIVED RECORDING)HARRIS: T-minus 10, nine, eight, seven...VEDANTAM: On January 28, 1986, the Challenger spacecraft blasted off from Cape Canaveral in Florida.(SOUNDBITE OF ARCHIVED RECORDING)HARRIS: ...One, and liftoff. Liftoff of the 25th space shuttle mission, and it has cleared the tower.VEDANTAM: Seconds after liftoff into into a clear blue sky, something went wrong.(SOUNDBITE OF ARCHIVED RECORDING)STEVE NESBITT: Flight controller's here looking very carefully at the situation. Obviously, a major malfunction.VEDANTAM: It was much more than a malfunction; it was a disaster. As millions of people watched in horror, trails of smoke and debris flew off in different directions.(SOUNDBITE OF ARCHIVED RECORDING)NESBITT: We have a report from the flight dynamics officer that the vehicle has exploded.(SOUNDBITE OF ARCHIVED RECORDING)UNIDENTIFIED REPORTER #1: What appears to be a major catastrophe in America's space program, Challenger, only seconds after leaving the launchpad, according to NASA, has exploded in midair.(SOUNDBITE OF MUSIC)VEDANTAM: After the explosion, NASA officials were hauled to Capitol Hill and put to questioning.(SOUNDBITE OF ARCHIVED RECORDING)UNIDENTIFIED PERSON #1: Who finally made that decision to go? What was the chain? How did that link? What happened then specifically?VEDANTAM: Members of Congress asked the tough questions - how could this have happened? Who's to blame? Were there warning signs that were ignored? These are the kinds of questions we have when any catastrophe occurs, whether a spacecraft has exploded or a city's been attacked by terrorists. In all these cases, we want to know - who screwed up?(SOUNDBITE OF ARCHIVED RECORDING)RICHARD CLARKE: Your government failed you. Those entrusted with protecting you failed you. And I failed you.VEDANTAM: We ask who knew what, when?(SOUNDBITE OF ARCHIVED RECORDING)ADAM GOLDMAN: The State Department had received repeated warnings that the situation was getting worse.VEDANTAM: And we try to figure out how...(SOUNDBITE OF ARCHIVED RECORDING MONTAGE)UNIDENTIFIED PERSON #2: How do we make sure...UNIDENTIFIED PERSON #3: That this kind of breach...UNIDENTIFIED PERSON #4: That such an accident...UNIDENTIFIED PERSON #3: ...Does not ever happen again.UNIDENTIFIED PERSON #4: ...Never happens again.VEDANTAM: With many of these incidents, there's a sense that they could have been avoided, that someone knew something but didn't say anything - or if they said it, they weren't believed or if they were believed, nothing was done. This week on HIDDEN BRAIN, the psychology of warnings - why some warnings get heard, why many are ignored and the pitfalls of being a prophet.(SOUNDBITE OF MUSIC)VEDANTAM: We begin this tale of warnings made and warnings ignored in the middle of Alaska. I'm in a car riding on a weather-beaten road that leads out of Fairbanks. Chris Hiemstra is driving, and he points out something.CHRIS HIEMSTRA: And you can see in the road here - you see all these bumps and all these curves.VEDANTAM: These aren't your standard potholes. The state of the road is a sign of something far more significant. Beneath the pavement, the ground is disintegrating. What lies below the asphalt is the Alaskan permafrost, and it's melting.HIEMSTRA: Permafrost is any soil or ice or rock that's frozen for more than two years, like two consecutive years.VEDANTAM: Picture the plants and animals that lived in Alaska over the past tens of thousands of years. After they died and fell to the ground, they froze. Permafrost is made up of layer upon layer of this organic frozen material. There's a place where you can see what's happening deep inside this permafrost. It's a tunnel that's hundreds of feet long. It's built into the side of an Alaskan hill.Chris is a research scientist at the Army Corps of Engineers. He works in the Cold Regions Research and Engineering Laboratory out of Fairbanks. He has spent a lot of time in this tunnel, and he's taking me there today to show me something important.HIEMSTRA: There's 40,000 years of Earth history that's stored and frozen in time.VEDANTAM: To get to that frozen history, we walk through a set of gates...(SOUNDBITE OF GATE CLANGING)VEDANTAM: ...Over to a wood cabin.Whole bunch of hardhats.We head over to what looks like a nondescript wooden shed. It has a sign on the outside that says U.S. Army Corps of Engineers and a warning to watch your step. Inside, it's pitch black. At the far end, there's another door that leads into the actual tunnel. Chris turns on the lights and leads me through. We walk down to a lower area. The deeper we go...HIEMSTRA: The lower down you go into the tunnel, the older you are in sediment.VEDANTAM: ...The further back we move in time.HIEMSTRA: OK. So - like, back over here...VEDANTAM: When Chris describes what's in the tunnel, he's even-toned. But what I can see all around me is completely extraordinary.HIEMSTRA: So on that, that's like a 43,000-year-old piece of, probably, willow that's been sitting down here for quite a while.VEDANTAM: Forty-three-thousand-years-old.It actually looks like it could have fallen last year.HIEMSTRA: Yeah, it's amazing, the cold temperatures and how long it can be - organic matter can be preserved here.VEDANTAM: If you're picturing this like a real-life trip on the Magic School Bus, you're right - except there's one part of the experience that doesn't exactly fill me with wonder.HIEMSTRA: I think the aroma is one thing that people notice right away.VEDANTAM: I was just going to ask you - is it just me, or does this place stink?HIEMSTRA: (Laughter) It's definitely got an unusual smell. And that's your organic matter that's coming back into the atmosphere.VEDANTAM: All around me, the decaying plants and animals smell like food gone bad in a freezer. The smell is unpleasant, but what it ought to be is terrifying. Something is happening here that has consequences for the entire planet. The organic matter trapped in the permafrost - fungi, plants, animals - it's thawing. As it thaws, it decays. And as it decays, it releases extraordinary amounts of carbon into the atmosphere. How much carbon? Scientists say the amount of carbon that's stored in the permafrost is about double of what's in the entire atmosphere. Let me say it again - double.HIEMSTRA: It's in the deepfreeze. What happens if that temperature goes up or, for some reason, it thaws a little bit more? What happens to that carbon? A place you don't necessarily want it is back in the atmosphere.VEDANTAM: We don't want it back in the atmosphere because carbon dioxide contributes to climate change. But a vicious cycle has already started. As the planet warms, the permafrost thaws. All those dead animals and plants and fungi start to decompose. More decomposition means more carbon released into the atmosphere, which means warmer temperatures, which means even more melting of the permafrost. What follows is disaster.(SOUNDBITE OF ARCHIVED NPR BROADCAST MONTAGE)AUDIE CORNISH: The fire storm in Australia has burned an area as large as West Virginia, and the smoke from those fires is making its way around the globe.RACHEL SMITH: It started raining and - no big deal. And then we see the water going down the street start to get a little bit higher, until it's up to the curb of the sidewalk.UNIDENTIFIED PERSON #5: Oh, my God.UNIDENTIFIED PERSON #6: Ma'am, what's going on?ROB SCHMITZ: At the rate global temperatures are rising, 60% of all the glaciers here in Xinjiang - nearly 11,000 glaciers - will be gone within 50 years.VEDANTAM: Chris doesn't need to turn on the news to see what rising temperatures are doing to the planet. When he's in the tunnel, he can see it right in front of his eyes. He can smell it. He's reminded of it every time he drives on the cracked pavement. And there's a feeling that he can't escape. It comes when he's at work, when he talks to strangers - even when he's in the comfort of his own car. That feeling is futility. He can see a catastrophe unfolding in front of him, but no one seems to be listening. Or people seem to be worried about the wrong things, like in a conversation he had earlier in the day.HIEMSTRA: The claim was made that most of the CO2 in the atmosphere comes from volcanoes, which isn't the case.VEDANTAM: Who made the claim?HIEMSTRA: It was somebody on the school field trip earlier today. And I pushed back against that politely. And it's hard because you've got to be really - it's so hard to be - you know, you don't want to offend people. You don't want to - because making someone angry isn't going to change their mind at all. So you got to be really careful about how you wade into things. And you don't know this person necessarily, and there's not a familial tie. So it's a stranger, someone who's - all we have, really, in common is that our kids go to the same school and they're in the same class.But it was a crucial piece of misinformation that wasn't true. And then - so what do you - you just say, like, flat-out, like, that's not true? That's going to shut everything down, and it's not going to help me in any way; it's just going to make somebody who thinks I'm a jerk.VEDANTAM: To Chris, it seems as if the pushback he gets is driven by a larger contempt that some people feel toward science and scientists.HIEMSTRA: Like, it's not relegated or limited to your work; it's a critique of you as a person, as if, like, you're just trying to lie to people about the work you do, which doesn't make any sense. I mean, your stock as a scientist is because of your honesty. If you're not honest as a scientist, your career is over - and it should be over.VEDANTAM: Chris feels invisible. He works in a remote place 40 feet below the surface in a part of the country that's unfamiliar to most Americans.HIEMSTRA: A lot of them will never make it up here. A lot of them won't go into the permafrost tunnel. A lot of them won't go run up above the tunnel or throughout Alaska where permafrost exists or even understand what it looks like, what it smells like. So how do you communicate that? How do you say, like, there is a value in you understanding what you don't currently understand?VEDANTAM: How do you get people to see that there is value in understanding what they don't understand? Chris' question is an ancient question. For millennia, we've often shunned and shamed people who have warned us of looming disaster. Why does this happen? Why do human beings who care about their survival ignore warnings of doom?When we come back, we're going to do something unusual. We're going to look for answers to that question, not in science but in literature. We're going to dive into Greek mythology and talk about a doomed prophet. The lessons from her story still resonate today.(SOUNDBITE OF MUSIC)VEDANTAM: In Greek mythology, the gods loom large - so large that many of them fill our imaginations even today - Zeus with his thunderbolts; Aphrodite, the goddess of love; Hades, in charge of the underworld; Athena, goddess of wisdom. The gods of ancient Greece moved among humans. Some of those humans were themselves touched with divine powers. One of the most striking was the prophet Cassandra. Cassandra remains so memorable that her story has inspired movies, television, even campy pop music.(SOUNDBITE OF SONG, "CASSANDRA")ABBA: (Singing) Pity, Cassandra, that no one believed you...VEDANTAM: In 1982, the Swedish band ABBA dedicated a song to her more than 2,500 years after she was first memorialized by Homer, Aeschylus and Euripides.(SOUNDBITE OF SONG, "CASSANDRA")ABBA: (Singing) Sorry, Cassandra. I didn't believe you really had the power.VEDANTAM: This power that Cassandra had was incredible - except there was one problem. No one believed her.EMILY WILSON: It's not Cassandra's fault that she's not believed.VEDANTAM: This is Emily Wilson.WILSON: I'm a professor of classical studies at the University of Pennsylvania.VEDANTAM: Emily is going to take us back to the legend of the kingdom of Troy. She's going to help us understand what this ancient myth still has to teach us.(SOUNDBITE OF MUSIC)VEDANTAM: Cassandra's father, Priam, was the king of Troy. It's safe to say that Cassandra didn't suffer from only child syndrome.WILSON: Priam has, according to different accounts, either 50 or a hundred children. She's one of the many children of Priam.VEDANTAM: Cassandra has a blessing that is really a curse - she can see the future, but no one will believe her. But even if you set aside the curse, it turns out she also did several things that made it less likely she would be believed. For one thing, her prophecies were opaque. When she revealed her visions, she spoke in language that was a little hard to understand.(SOUNDBITE OF PLAY, "AGAMEMNON")UNIDENTIFIED ACTOR: (As Cassandra) What's this in front of my eyes now? Is it a hunting net out of the underworld? Yes, but a man trap, too, that sleeps with him, helps plot his murder. Let the mob endlessly gorging on this clan raise a shriek over the sacrifice on which stones will fall in their turn.WILSON: She speaks primarily in symbols and metaphors - that she can foresee the ox killed at the altar; she can foresee blood and slaughter. She doesn't speak in a way that sort of spells out exactly - as soon as I walk into this house, Clytemnestra is going to take the ax and hack us both to death - because that's not the way oracles speak. She speaks in prophetic language.VEDANTAM: Cassandra's best-known prophecy had to do with one of the world's most famous carpentry projects, the Trojan horse. There's a war between the Trojans and the Greeks, and it's dragging on.WILSON: It keeps going for 10 years without decisive victory on either side.VEDANTAM: The turning point comes when the Greeks have an idea.(SOUNDBITE OF MUSIC)WILSON: That they should build a great, big wooden horse and have their best warriors on the Greek side hide inside the wooden horse. They leave the great, big wooden horse outside the walls of Troy.VEDANTAM: As the Trojans watch from their city, the Greeks get in their ships, seemingly in defeat, and sail away. Their mysterious gift remains on the beach, and the Trojans debate whether to throw open the city gates and bring in the horse.WILSON: Is this some kind of gift for the gods? Is it a holy offering? Should we mistrust it? Should we not mistrust it?VEDANTAM: Cassandra knows that this gift is not a gift at all. She tells her fellow citizens not to open the gates of Troy. In her own convoluted way, she says, this is a terrible idea; don't do it. But she doesn't have any real power. Her fellow Trojans don't recognize her as a prophet, and so she's not taken seriously. The consequences are disastrous.WILSON: The Trojans decide, in the end, to bring the horse in. And then, of course, in the middle of the night, the Greek warriors spring out of the horse and start slaughtering the citizens inside the city.(SOUNDBITE OF METAL CLANGING)VEDANTAM: You'd think that after Cassandra accurately predicts the fall of Troy, some people might start believing her. You'd be wrong. She makes another prediction that fails to gain any traction. As the city is burning and the women of Troy are forced to board Greek ships as slaves, all the prisoners are distraught - all except Cassandra, who seems weirdly happy.WILSON: Her mother seems deeply concerned about her - (laughter) worried for her, as one would be, for her daughter who keeps saying crazy stuff and who also seems to have this perverse idea that being taken into slavery could be a good thing.VEDANTAM: There's a reason why Cassandra has this oddly positive reaction. Whereas everyone else can only see what's right in front of them, she can see two steps ahead. She already knows something about her situation. She knows she is going to die, but so is her captor, the Greek general Agamemnon. Revenge is coming, even if it means her own death.WILSON: Cassandra sees a gleam of hope in the fact that she knows Agamemnon is going to be murdered horribly. She can see that there's going to be bad things for the Greeks down the line.VEDANTAM: So to recap, there are several things besides the curse that make Cassandra less likely to be believed. She speaks in cryptic language. She doesn't have any formal authority. She's too far ahead of everyone else. There's one more thing. She asks too much of the people she warns.This happens when Agamemnon takes Cassandra back to Greece with him as a slave. They go to his home. Agamemnon doesn't know that, during his absence, his wife Clytemnestra has started an affair. He doesn't know that Clytemnestra is not pleased to have him back. But she pretends to be happy.WILSON: So she welcomes him into the house, along with Cassandra as his human property. He goes first into the house, and then Cassandra pauses to give these prophecies, these riddling prophecies.VEDANTAM: Cassandra foresees his death and her own.(SOUNDBITE OF PLAY, "AGAMEMNON")UNIDENTIFIED ACTOR: (As Cassandra) Look at this. Look. Keep the bull away from the heifer. She's caught him in her dress, her engine, on her black horn, striking. Into the basin he falls, where the water lies. He met his death in the bath. It lay in wait for him, I tell you.VEDANTAM: Or, to translate - Clytemnestra is about to hack her husband to death with an ax. For Agamemnon to take Cassandra seriously, he would have to see that his life was in danger, that his wife despised him - that far from being a victorious warrior, he was walking into a deathtrap. To save his own life, he would have to change his entire outlook.WILSON: He wants to think of himself as a strong, triumphant city-sacker. And he's only going to process the information that confirms that belief about himself. And he's going to ignore all the signs, both from Clytemnestra and from Cassandra, that might suggest that reality is not the only reality and, in fact, you're missing a whole lot of information here.VEDANTAM: Things play out just as Cassandra predicted.(SOUNDBITE OF PLAY, "AGAMEMNON")UNIDENTIFIED ACTOR: (As Cassandra) She's caught him in her dress, her engine, on her black horn, striking.WILSON: Clytemnestra gives him a lovely bath. And she entraps him in a net, as well, in order to make sure that if he struggles after the first blow, he won't get away. So she strikes him multiple times till he's good and dead and also hacks Cassandra to death.VEDANTAM: This sounds like it was a particularly gruesome murder, but maybe I'm wrong. Maybe this is par for the course in Athenian tragedy.WILSON: Oh, I think it's par for the course. I mean, it's much less gruesome than the death of Pentheus, say, yes.(LAUGHTER)WILSON: Because there's usually some gory death, yeah. Why else would you go to the theater?(SOUNDBITE OF MUSIC)VEDANTAM: Now, of course, Cassandra was cursed. By definition, it didn't matter how persuasive she was; she was never going to be believed. But her failed attempts to warn those around her can give us insights into how warnings are heard, whether they're taken seriously and when they're acted upon. When we come back, how can real-life Cassandras undo the curse and actually be believed?(SOUNDBITE OF MUSIC)VEDANTAM: This is HIDDEN BRAIN. I'm Shankar Vedantam. This is what a Cassandra who's effective sounds like.ANDREW NATSIOS: I speak loudly all the time because I'm kind of aggressive person, you know. Even though I'm - I'll be 70 next year. My wife said, will you please calm down? She's been saying it for 43 years now, and it hasn't happened.VEDANTAM: The actual name of this Cassandra is Andrew Natsios. His moment of prophecy involved a life-and-death choice that affected hundreds of thousands of people. Before we get to that, we need to understand the formative moments in Andrew's career. In many ways, he was an unlikely hero. In the 1980s, he served in the Massachusetts House of Representatives. At a Republican National Committee meeting in 1988, he didn't exactly get the star treatment.(SOUNDBITE OF ARCHIVED RECORDING)UNIDENTIFIED PERSON #7: Chair recognizes...UNIDENTIFIED PERSON #8: Natsis (ph).UNIDENTIFIED PERSON #7: ...Natsis - Mr. Natsis from Maryland.UNIDENTIFIED PERSON #8: Massachusetts.UNIDENTIFIED PERSON #7: Massachusetts.NATSIOS: Natsios from Massachusetts, right.UNIDENTIFIED PERSON #7: Natsios.UNIDENTIFIED PERSON #8: Natsios.UNIDENTIFIED PERSON #7: Poor printing here, sorry.VEDANTAM: Before he got to his Cassandra moment, Andrew was brought in to salvage a boondoggle of a transportation project in Boston - the Big Dig. It redirected a massive highway into a tunnel under the city. Andrew came in several years into the project. At that point, it was a mess with huge cost overruns. Andrew had two things going for him - he had experience leading big institutions, and he had his temperament.NATSIOS: I'm sort of a Type A personality, very kind of aggressive and a dominant figure in any institution that I run. So I could get the institution to do what I wanted it to do, what I thought was right to do.VEDANTAM: He was, in fact, able to figure out why the project's finances were out of whack. But his efforts weren't always appreciated.NATSIOS: It was the most difficult year of my career. Actually, I actually felt safer in Sudan and Iraq and Afghanistan than I did in Boston. One person threatened to break my neck while I was (laughing) investigating the Big Dig. And I was threatened once I took over, too. Someone threatened to kill me then, too.VEDANTAM: Andrew had spent much of his career overseas. His experience leading several national and international organizations caught the eye of President George W. Bush, who appointed him to lead USAID. That's the agency responsible for America's involvement in international development. It's here that Andrew had his prophetic moment.(SOUNDBITE OF MUSIC)VEDANTAM: In 2003, Andrew briefed top members of the Bush administration about escalating violence in Sudan. By that point, marauders were charging into villages, setting them on fire, sending civilians fleeing. They were known as the janjaweed. They quickly took over a vast and dusty region on the edge of the Sahara - Darfur. Andrew's warnings and advice had an impact. The U.S. supplied billions of dollars in aid to Sudan over the next several years.(SOUNDBITE OF ARCHIVED RECORDING)PRESIDENT GEORGE W BUSH: In spite of the economic difficulties, our aid will continue to flow.VEDANTAM: President Bush also put political pressure on Sudanese leaders. Some of his measures were behind the scenes, others more public. The news media began to take note.(SOUNDBITE OF ARCHIVED RECORDING)UNIDENTIFIED REPORTER #2: Today President Bush announced tough new economic sanctions against Sudan over the continued persecution of the minority population in Darfur.VEDANTAM: Andrew's actions at USAID have become a case study on effective warnings. That's according to Christoph Meyer.CHRISTOPH MEYER: I'm a professor of European and international politics at King's College London.VEDANTAM: Christoph has spent many years studying how warnings are made and which ones manage to break through the noise. He says there are several reasons Andrew Natsios managed to persuade the Bush administration to act.MEYER: One is he was able to show how further escalation, with many hundreds of thousands of people dead, was highly likely. And he was able to kind of put that into a presentation, you know, chart the escalation of the conflict into the future.VEDANTAM: Andrew commissioned a study that predicted how many people would die if the U.S. didn't intervene. He also got U.S. spy satellites to take pictures of Darfur.NATSIOS: To photograph the ground every day to show the villages that were being burned from day to day. And these photographs were so clear that the photographs were unimpeachable in terms of their quality, in terms of what the atrocities were. And they burned 3,800 villages. They displaced 2 million people.VEDANTAM: So Andrew laid out clear evidence. There was something else that helped him make the case to the president - he was an insider.NATSIOS: Was I taken seriously? Yes because I had a relationship with the presidents.VEDANTAM: That's presidents - plural. He had campaigned twice for George H.W. Bush, and he had worked on the George W. Bush campaign in 2000.MEYER: He was not seen as one of these, you know, do-gooders, one of these kind of liberal NGO types. Yes, he had a history in the NGO sector. He was an expert. But he was - had also kind of a conservative pedigree. He had experience in the armed forces. He was seen as someone who understood that the president's time was precious and understood the preferences. And he was seen as kind of part of us.And therefore, if someone who was seen as a kind of - someone who was kind of almost a national security type. If someone like that would warn about the consequences of that kind of conflict in that country, he would be taken so much more seriously than someone who is seen in a much - in a very different light.VEDANTAM: Besides his political credentials, Andrew was also an insider in another way. He was a Christian who had spent years leading an international Christian NGO. He knew that George W. Bush's identity as a Christian was important to him and important to his reelection chances in 2004. Christoph Meyer says Andrew laid out the political consequences of inaction in Darfur, where many of the civilians being attacked were Christian.MEYER: He was able, then, to show how that kind of escalation would be politically relevant to the Bush administration at the time, how it would impact on the reelection chances and how it would connect to Christian constituency in the U.S., which of course were one of the supporting constituencies of the Bush administration because it was also Christians who were - in Sudan - were largely affected by this violence.VEDANTAM: Andrew implicitly understood a widespread psychological bias. We all tend to look more sympathetically at suffering when the people who are suffering have something in common with us. There's another part to this. Andrew was successful because he didn't ask President Bush to make a major U-turn. From the very beginning of his administration, the president had been interested in what was happening in Sudan.NATSIOS: The first presidential review that the president ordered was on Sudan policy.VEDANTAM: Now, what came to be known as a genocide in Darfur did claim hundreds of thousands of lives, so it may be hard to see Andrew's warning as effective. And yet, if Andrew had not acted, Christoph says he believes things would have turned out worse.MEYER: I think the Bush administration did act. It didn't act very early, but it did act politically to put pressure on the conflict parties. And they did act, I think, as soon as could be probably expected on the humanitarian front, therefore saving lives through humanitarian action.NATSIOS: I couldn't have done that alone, but President Bush did it. I have to say - I said it in my book - I think he ended what could have been another Rwanda genocide.(SOUNDBITE OF MUSIC)VEDANTAM: So in Andrew Natsios, we have a plainspoken leader. He had the insider credentials to get others on board. And he didn't ask policymakers to do something that was greatly at odds with what they wanted to do anyway. Contrast that with the doomed prophet we heard about earlier. Cassandra spoke in riddles - prophetic riddles but riddles nonetheless.(SOUNDBITE OF PLAY, "AGAMEMNON")UNIDENTIFIED ACTOR: (As Cassandra) Let the mob endlessly gorging on this clan raise a shriek over the sacrifice on which stones will fall in their turn.VEDANTAM: Unlike Andrew Natsios, Cassandra wasn't an insider. As Emily Wilson says...WILSON: Even if somebody is speaking the truth, if it's coming from the mouth of an unauthoritative person or somebody who's dismissed as othered, then that can make it possible to dismiss even a very clear articulation of a scary truth.VEDANTAM: And Cassandra was too far ahead of everyone else. When she and the other Trojan women are being captured as slaves, she doesn't explain that she is happy because she knows the Greeks are going to be killed. She can see into the future, but she doesn't take others along with her.There are lessons here for our own time. Christoph says many modern Cassandras forget it's hard for most people to look far into the future. Leaders, especially, are often pulled in different directions. Paying attention to one risk means fewer resources for others. If you come in with a vague warning about a distant problem, you're going to get sidelined.MEYER: Samantha Power wrote in her book "A Problem From Hell" about the response from one administrator to the warning that was given - that unless his telephones were ringing, he couldn't do anything. So even if he believed that what she was saying is right, he was so constrained by the lack of, in a sense, public clamoring in the Beltway, the kind of support for acting, that he couldn't do something.(SOUNDBITE OF MUSIC)VEDANTAM: Cassandra also asked the people she was trying to warn to stretch too far outside their comfort zone. Remember when Clytemnestra is giving Agamemnon a lovely bath before she hacks him to death? Cassandra saw it coming.(SOUNDBITE OF PLAY, "AGAMEMNON")UNIDENTIFIED ACTOR: (As Cassandra) Look at this. Look. Keep the bull away from the heifer.VEDANTAM: But Agamemnon wasn't in a headspace where he could hear the warning. Christoph says this happens with real-life Cassandras and real-life policymakers. If leaders have to reject some foundational belief to act on a warning, there's a strong chance that they will simply ignore the warning.MEYER: Quite often, what makes warnings so difficult to believe is their political inconvenience.(SOUNDBITE OF MUSIC)VEDANTAM: In fact, this is exactly what happened in the case of the Challenger space shuttle disaster. A scientific inquiry found that several engineers had had concerns about the safety of what came to be known as the O-rings on the shuttle. They told NASA managers to delay the launch. But the managers overruled the engineers, and the Challenger took off as planned.(SOUNDBITE OF ARCHIVED RECORDING)NESBITT: Flight controller's here looking very carefully at the situation. Obviously, a major malfunction.(SOUNDBITE OF MUSIC)VEDANTAM: We've painted a picture of warnings that is at odds with the way most of us think about them. In the conventional telling, someone raises an alarm, and everyone jumps up and does something about it. In reality, warnings are likely to be heard when they're made by someone who's part of our in-group, when the warning is so imminent that nearly everyone can see the danger and where the solution doesn't require a radical shift in existing strategy. Unsurprisingly, this means that many warnings will go unheeded, and many Cassandras will be dismissed.In Greek mythology, Cassandra was cursed to be ignored. There really wasn't anything she could do to get people to believe her. For the Cassandras in our own midst, the curse is even more terrible. Facets of the human mind make it difficult for us to pay attention to warnings and difficult to act on them until it's nearly too late.(SOUNDBITE OF MONTAGE)UNIDENTIFIED PERSON #2: How do we make sure...UNIDENTIFIED PERSON #3: That this kind of breach...UNIDENTIFIED PERSON #4: That such an accident...UNIDENTIFIED PERSON #3: ...Does not ever happen again.UNIDENTIFIED PERSON #4: ...Never happens again.(SOUNDBITE OF MUSIC)VEDANTAM: This week's episode was produced by Rhaina Cohen and Thomas Lu. It was edited by Tara Boyle and Jenny Schmidt. Our team includes Parth Shah, Laura Kwerel and Lushik Waba (ph). Our Unsung Hero this week is Sophia Dawkins. Sophia has spent years studying the conflict in South Sudan. She patiently helped us understand the complicated history of the region in order to get the nuances right. Sometimes the most important contribution someone can make to a story is to get things out of the story. Thank you, Sophia.You can find more HIDDEN BRAIN on Facebook and Twitter. If you like the show, please tell one friend today about our program. I know from both my personal experience and the social science literature that word-of-mouth recommendations really matter. If you love HIDDEN BRAIN, please spread the word.I'm Shankar Vedantam, and this is NPR.(SOUNDBITE OF MUSIC) Transcript provided by NPR, Copyright NPR.