Would You Kill One To Save Five? Your Brain Already Decided

Can we store summer’s heat to warm our homes in winter? Could humans perceive a fourth dimension? And why does light bend around gravity even though it has no mass? Small questions from YOU which open doors to enormous worlds. In this episode of Field Notes, Hannah Fry and Michael Stevens discuss underground heat batteries in Canada and Einstein’s thought experiments, from how the universe hides its secrets and how we uncover them. Later, Michael presents a story which leads to an exploration of human behaviour, the experiments that reveal how authority influences our actions and why ordinary people can be pushed to act against what they say their values really are. Welcome to The Rest Is Science: Field Notes. Every Thursday, Hannah and Michael share the science behind the world around us from the surprising to the unsettling and show how it shapes both the universe and ourselves. ------------------- For more information about Cancer Research UK, their research, breakthroughs and how you can support them, visit ⁠⁠https://cancerresearchuk.org/restisscience⁠⁠ Cancer Research UK is a registered charity in England and Wales (1089464), Scotland (SC041666), the Isle of Man (1103) and Jersey (247). A company limited by guarantee. Registered company in England and Wales (4325234) and the Isle of Man (5713F). Registered address: 2 Redman Place, London, E20 1JQ. ------------------- Find The Rest Is Science all over the internet by ⁠⁠clicking here.⁠⁠ ------------------- Video Producer: Adam Thornton + Oli Oakley Video & Social: Bex Tyrrell Assistant Producer: Imee Marriott Producer: Becki Hills Senior Producer: Lauren Armstrong-Carter Head Of Digital: Samuel Oakley Exec Producer: Neil Fearn Learn more about your ad choices. Visit podcastchoices.com/adchoices

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Hannah Fry?

  This episode is brought to you by Cancer Research UK.

• 0:02Michael Stevens?

  So when most people think of naked mole rats, their unusual relationship to cancer probably isn't the first thing that comes to mind.

• 0:10Hannah Fry?

  But maybe it should be because it is incredibly rare for them to develop cancer, which could be partly down to their unique immune system, or it might be the way that their cells respond to damage.

• 0:22Michael Stevens?

  So scientists are studying their biology for its cancer-fighting secrets. It's a reminder that discoveries can sometimes come from places you don't expect.

• 0:31Hannah Fry?

  Cancer Research UK is the world's largest charitable funder of cancer research. Thousands of scientists, of doctors and nurses, work across more than 20 countries to help turn discoveries in the lab into new tests, new treatments and new innovations.

• 0:46Michael Stevens?

  And the impact is clear. Over the past 50 years, the charity's pioneering work has helped double cancer survival in the UK, meaning more people living longer, better lives, free from the fear of cancer.

• 0:59Hannah Fry?

  For more information about Cancer Research UK, their research, their breakthroughs and how you can support them, visit cancerresearchuk.org/restiscience.

• 1:09Speaker 02

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• 1:40Speaker 03

  This episode is brought to you by Indeed. You're ready to level up your business, but the pressure to find the right person to make that happen is intense. Indeed sponsored jobs can help carry the load. It boosts your job post to help it reach quality talent fast. Cut through the chaos with Indeed sponsored jobs. Get a $75 sponsored job credit at indeed.com/podcast. Terms and conditions apply. Hiring now? Then this is a job for Indeed sponsored jobs.

• 2:16Michael Stevens?

  Welcome to The Rest Is Science. This is Field Notes, a kind of podcast expedition diary where Hannah and I share some of the thoughts we've been carrying around, thrilling discoveries and big questions, whatever's been occupying our minds.

• 2:31Hannah Fry?

  I mean, some people call it thoughts, other people call it burdens, but every week we're gonna do three.

• 2:36Michael Stevens?

  I call it all I've got.

• 2:40Hannah Fry?

  Yeah, I mean, that's fair. We're gonna bring something from up from up of our biol science mystery bag. We're gonna, we're gonna bring something to show each other. It's just like a rest of science is very own version of show and tell. And yeah, this week it's your turn, Michael.

• 2:54Michael Stevens?

  That's right. And so later in the episode, I am going to share a story, actually. A story about the scariest moment for me ever in the mind field psychological experimentation show I did. And it's not what you're expecting.

• 3:12Hannah Fry?

  Well, I mean, you were the man who locked himself away for three days and started hallucinating. So if it's scarier than that, then I think the rest of us need to buckle up. As ever, we would also like to hear your questions, your theories, your thought experiments, maybe not your burdens. You can send them in to us and we'll dust off a shelf for you. You can, you can join our vast collection of curiosities.

• 3:34Michael Stevens?

  Yeah, we'd love to put you there. So let's begin with Francois, who sent in a question. "It seems such a waste to spend energy adding heat to our houses in winter and spending more energy on AC to remove it in summer. Could we feasibly design a machine that pumps heat into a form of reverse fridge during summer, stores it, and then pumps the heat back into our homes in the winter?"

• 3:56Hannah Fry?

  I mean, Francois, you have, you have a mind that is a marvel, but unfortunately, you've invented something that's already exists. Because this machine you're describing is called a seasonal thermal energy storage system. And it's essentially, it's like a big battery, but for heat. The problem is, if you try and store heat, it leaks quite a lot, right? If you put a cup of tea in a thermos, come back the next morning, it's gonna be cold, right? He has this. Habit of like sneaking away, but there are some places where they do this. So there's a particular neighborhood in Canada known as Drake Landing, where it gets really warm in the summer, but also extremely cold in the winter.

• 4:39Hannah Fry?

  I mean, like that sort of part of the world has a like massive variance in summer and winter temperature. And what they did there is they they built fifty two houses that were all connected to this massive underground storage field. So in the summer, what they do is they have all of these solar panels on their roof. And they use that to pump this solution, basically, down into this massive underground chamber, where they have all of these boreholes, and they literally heat up the rock that sits down there to about eighty degrees centigrade. And then in the winter, when it's like freezing cold up top, they reverse the process. They pump water through these like very warm rocks and use it all to to heat up their houses up top.

• 5:23Hannah Fry?

  You know, the London Underground is basically a perfect demonstration of the way that that the earth itself can hold on to energy in the form of heat.

• 5:36Michael Stevens?

  I was gonna say, that's impressive that the rock can hold the heat so well. This happens in the Underground in London as well.

• 5:43Hannah Fry?

  Yeah, because right in the early days when the Underground was built, it was like ten fifteen degrees in there, the clay, the sort of London clay. It was actually quite cold down there, but after, you know, a hundred and fifty years or so of all of these trains moving in and out of tunnels, of people, of that energy being continually pushed in, it sort of saturated the heat capacity of the of the the clay itself. The clay cannot take on any more heat effectively, so all of the heat just continues to be down there. It could be forty degrees down there in winter. You you actually get more people fainting in the underground during winter than in summer, when it is also insufferably hot. But in winter, people are also wearing all of these like coats

• 6:25Hannah Fry?

  and things. So the earth itself is actually very capable of of of like holding on to working as this this heat battery. It works really well in this place in in in Canada. There's a there's another example, a Finnish company who've done this as well. They're using sand instead. This massive silo filled with sand and they sort of heat the sand up to this crazy numbers, like sort of 500 degrees C, using renewable energy in the summer and then blow air through it in the winter to to give them heat back. The only problem with this is that if you wanted to like install one of these batteries yourself, if you want to say, okay, you know what, I can dig down, however many, I could dig a kilometer down under my own house and have my own little

• 7:10Hannah Fry?

  battery.

• 7:11Michael Stevens?

  That's what I think.

• 7:12Hannah Fry?

  I know. I know. That's what you're thinking. The slight problem with this is that, I mean, there's it's the the the square cube law is going on here, right? Which is this? Actually, the surface area to volume ratio needs to be, you basically need to do it for a lot of houses simultaneously for for the heat not to escape. You need like 50 houses at once. But if you know, if Francois, you happen to be a housing developer, who wants to like heavily invest in minimizing energy bills for the future of your potential homeowners, then I mean, this is a great way to do it. Just as long as you don't mind a bit of sand in your in your water, in your shower.

• 7:50Michael Stevens?

  Or your air.

• 7:51Hannah Fry?

  Or your air. Exactly.

• 7:52Michael Stevens?

  Ah, turn on the dust storm. I'm getting chilly.

• 7:59Hannah Fry?

  Okay, next question. We had one question come in from a guy from Slovenia, in fact, who said, do you think there will ever be at all an invention that humanity creates, which would let us gaze into a different dimension?

• 8:12Michael Stevens?

  Oh, wow. I love this question because it's, um, I I hope so much that before I leave this earth, I get to look in a direction that isn't one of the three I was born into. So boring, looking in the same three directions the entire time. I know. I think that there's so much more out there. I feel like Belle from Beauty and the Beast. It's just, I'm just this provincial 3D blob. And I desperately want to not look up, down, left, right, forward, backward, but I want to look Anacata. And I think that, you know, things like, oh, we'll look in a history book. Then you're, you know, looking through time, a fourth dimension. I'm like, no, I want it to be spatial.

• 8:53Michael Stevens?

  And I think that the closest we are is unsatisfying. We can see the results, for example, of dimensional change. Look in a mirror. And every time you look in a mirror, you are looking at yourself as you would appear if you had been rotated in a fourth dimension, through a fourth dimension. Like, you can think about this as like an L shape. If this is stuck in a plane and it's moving around, it can never become this unless it gets rotated in a third dimension outside of the plane. And if we do that to our bodies, we wind up just like this, getting mirror reversed. So when I see my mirror image, I'm seeing what I would look like if someone from a fourth dimension grabbed me and rotated me

• 9:39Michael Stevens?

  out beyond these three dimensions that I live in. We have a lot of computer simulations that can simulate four dimensional objects, right? There are a lot of amazing games that allow you to do this, but they only show you three dimensions. And then the object like leaves for a little while, or part of it leaves and comes back in and you go, oh, it was transformed in more dimensions than I can perceive. Interesting. But it's not just the effects that I want. It's the, um, the actual direction. And I feel like it's too late for me. I think that children might be able... If we catch them early enough, they might be able to see. I think they're the tool.

• 10:24Michael Stevens?

  Because they haven't been ingrained into the three dimensions yet. Like, you know how if you look at kids, they'll, they'll sometimes when they're learning to, to form letters, they'll write words backwards and mirror reversed. It looks like an amazing feat that would be hard for me to do as an adult. And they're just like, oh, yep. And they write their name. Everything's perfectly reversed because to them, this and this are the same shape. Like they, they understand what is the same between anatomorphs, between mirror image pairs. And we unlearn that as we become more familiar with the universe that we live in. I do have somewhere a four dimensional Rubik's Cube. Let me see if I can find it.

• 11:07Michael Stevens?

  I, I don't think I've put on my wall yet. Let me look in the chill room, which maybe I'll show you guys one of these days.

• 11:13Hannah Fry?

  Chill isn't cold or chill isn't cool?

• 11:16Michael Stevens?

  Both.

• 11:20Michael Stevens?

  I'm so sorry. I don't know where the heck it is. It, it doesn't matter because I forget which kind of moves are allowed on it. So I would just make a fool of myself.

• 11:30Michael Stevens?

  But if you, if you, if you look up four dimensional Rubik's Cube, Melinda Green, a long time ago, made an interactive website where you can solve a four dimensional Rubik's Cube. It can be rotated in the three dimensions we're used to, but also this fourth one that kind of turns it inside out. Um, and it's phenomenal. And she's actually invented a physical version. And I've been talking to her about like, how do we make more of these? And, and what would you do if you had, you know, more resources? And she's like, ah, I would put lines on them to represent the like geodesics and uh, I, I'm very excited for it.

• 12:07Hannah Fry?

  That sounds really cool. I mean, impossible, but really cool. I do like the idea there of, of just getting, uh, getting a child as young as possible. And then just being to them like demanding to point where the fourth dimension is because they're the only ones who can possibly know.

• 12:22Michael Stevens?

  Exactly. They're the only ones. And from there, maybe, um, Guy, we could.

• 12:29Michael Stevens?

  Invent a tool to actually see it for ourselves.

• 12:33Hannah Fry?

  What if though, what if we are like Belle and actually, once we do get to the fourth or other dimensions, all that's to be found is beasts.

• 12:42Michael Stevens?

  But they won't really be beasts, but there will be Gastons who are afraid of that knowledge, that new vista that's been opened, and they will say, kill the beast, kill the fourth dimension, build walls to block it. And they may be right, but should they be right?

• 12:58Hannah Fry?

  Thing is, Michael, I think Beauty and the Beast was originally written as a little story that you would tell young, very young girls who are about to be married off to scary old rich men.

• 13:11Michael Stevens?

  To make them okay with it.

• 13:13Hannah Fry?

  It's like, you think he's a beast, because he is, but.

• 13:18Michael Stevens?

  Maybe if you put in a lot of work, you can fix him. Well, look, the fourth dimension is my old rich man. And I am jumping into, I'm jumping into this relationship with both feet. Okay?

• 13:33Hannah Fry?

  Yeah. Give me the candlestick, the teapot, and off we go. Okay, amazing.

• 13:41Michael Stevens?

  Let's move on to a question from Henry. Why does gravity bend light if light has no mass?

• 13:48Hannah Fry?

  It's a great question, isn't it? It's a great question. And the thing is, is that that doesn't make any sense if you stick to Newton's idea of what light is, of what gravity is, sorry, that it's like it's something that acts on mass. But Einstein's version of gravity is this, it's not the light that's bending, it's the space around the light that is bending. And that is why it appears to bend. It's not that it's like having a gravitational pull or gravitational effect. And I know that actually, we did this whole episode on gravity and we talked about. Um. There's still a slight problems with with imagining it as though it's a it's it's a bowling ball on a rubber sheet, which is the the one that sort of people talk about quite a lot. But there's a there's a slightly simpler way to think about this, I think.

• 14:32Hannah Fry?

  Imagine if you're standing in like a in an elevator in a lift. And you've got a laser and you're sort of pointing the laser over at the other side. Um, hitting the wall directly opposite the the elevator. And then all of a sudden, there's like a rocket engine under the elevator that blasts off, accelerating the the elevator up extremely fast. Now, the thing is, is that while the floor is rushing up, while the light is traveling across the room, the floor underneath it is rushing upwards so quickly that it means that by the time the light hits the wall, the wall will have moved up. Um. So to you, standing on the inside of the elevator, it looks like the laser beam is curving downwards because you're moving up incredibly fast.

• 15:15Hannah Fry?

  And what Einstein realized essentially, that's like the bending of the light, as it were. And what Einstein realizes that that acceleration feels exactly the same as gravity. There's there's two things, the the feeling of them, as it were, is sort of indistinguishable. If you if you wake up in a windowless box and you feel heavy, you don't know whether you're on earth or whether you're you're in a rocket that's accelerating at at one G. And so if acceleration can bend light, then gravity must also bend light. And the proof of this came in, um, like the really remarkable proof was of Einstein's ideas came in nineteen nineteen. It was a big eclipse. For years, it was just this cool theory, right? But then this solar, total solar eclipse happened.

• 15:58Hannah Fry?

  And astronomers, they, um, in nineteen nineteen, went to the site of the eclipse. And, um, they looked at stars that were directly behind the sun. Now, if light didn't bend, then during the the total eclipse, you shouldn't be able to see them. Right? You'd have to wait for different moments in the year, different times to be able to see those stars. But because the sun's gravity bends the light from those stars around.

• 16:25Hannah Fry?

  During the total solar eclipse, those stars appeared next to the sun. And the position of them, the position of those stars was shifted by exactly the amount that Einstein had predicted. So, and, and that experiment, that was what really made Einstein this, this celebrity overnight.

• 16:43Michael Stevens?

  Superstar.

• 16:44Hannah Fry?

  Superstar, yeah. He proved that light doesn't need mass to be pushed around. It's, it just needs this, this, this road that it follows.

• 16:51Michael Stevens?

  Yeah, the spacetime that it travels through is being curved and the light is just traveling in the geodesic, the straight line path and whoops, it happens to be curved. Guess I went around the sun into your eyeball. Peekaboo.

• 17:05Hannah Fry?

  This is really why Einstein has the reputation that he does. This is why everyone is still, you know, a hundred and whatever years later, still so completely flawed by the unimaginable foresight of this man. Like to be able to sit in a room and have a thought experiment like that elevator and conclude from it that during a total eclipse, you should still be able to see the stars that are hiding behind the sun and then ending up being correct. I mean, that really is just phenomenal. I mean.

• 17:40Michael Stevens?

  I mean, that's the dream. Your ideas are testable. They are tested in your lifetime and you were right. You predicted things we had not observed before.

• 17:51Hannah Fry?

  Absolutely. Well, okay, from predicting things that have not been observed before to hearing stories that have not been told before. Join us back after the break.

• 18:08Speaker 03

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• 19:44Michael Stevens?

  All right, welcome back. Hannah, have you ever had your mind experimented on by scientists?

• 19:50Hannah Fry?

  Not knowingly.

• 19:51Michael Stevens?

  Well, good. One of these days, I'd like to do some on your brain, but today I want to talk about the scariest experiments I've been a part of. I did this a lot in college for money.

• 20:05Hannah Fry?

  Did you?

• 20:06Michael Stevens?

  You could go in and make a few bucks by taking a survey, or you could make dozens of bucks by having them do an MRI scan on you.

• 20:14Hannah Fry?

  Are you one of the weird people that they talk about? The idea that psychology experiments are largely done on a particular type of person?

• 20:23Michael Stevens?

  Exactly. They're done by college undergrads who want five bucks to get a Big Mac, you know? And so, yeah, I was one of those. People that like the foundations of psychology are built on and continue to be built on. And I remember one time I did this MRI study and while they calibrated the machine, they had me watch a movie and I could pick a movie. And it was clear that they had three movies to choose from. One was for women, one was for men and one was for children. And the movie for children was Air Bud and I'd never seen Air Bud. So I'm like, yeah, I'll do Air Bud. So I'm watching Air Bud in this MRI machine while they calibrate the magnets to my brain. And the amount of time it took for them to calibrate the machine was the amount of time

• 21:08Michael Stevens?

  it takes for the kid in the movie to realize the dog can play basketball. So I got to watch everything but the dog play basketball. And I was so upset, it wasn't worth the 50 bucks I got paid and I'm still mad about it. I still haven't seen Air Bud.

• 21:23Hannah Fry?

  Did they not give you the option to continue the film?

• 21:27Michael Stevens?

  No, they were like, all right, now the experiment must commence. And I had to like recognize patterns and stuff. And I'm like, please put the dog back on the screen. Now I've seen clips of the dog playing basketball and I did a whole episode about whether or not a dog could play basketball according to the rules of the state that the movie appears in. I won't spoil it, but the conclusions were quite surprising. Anyway, psychological experiments is what we're talking about. When I was in high school, I had a psychology teacher that got me into psychology. It's why I studied psychology in college. But all he really did is play us videos. He played Candid Camera clips and then would talk about the psychology that was part of the prank we were watching.

• 22:11Michael Stevens?

  You know, Candid Camera is a TV show where people get pranked. Pranks are a big thing on the internet now and they can be amusing. They can sometimes be cruel, but often, almost all the time, you're learning a lot about how humans behave and how we think. So. I envisioned doing a prank show that was actually psychological experiments. Because so many experiments on human psychology are basically tricking people into thinking one thing and seeing what they do. And so in Mind Field, we did a lot of experiments that were, you know, pretty, pretty intense. We actually recreated the trolley problem.

• 22:52Hannah Fry?

  Right.

• 22:52Michael Stevens?

  We developed this intense ruse where people thought they were coming in to review these new high-speed railcar interiors, right? Is the fabric soft or the color's good? Is the lighting good? But then there was a delay and they had to go and wait in this air-conditioned room because it was a hot day. There was a switching room. And this old man that we hired, who used to switch railroad cars, like teaches them, "Yeah, I have to switch the lines because these guys are coming to work on it," and whatever. He shows them, and he's an affable guy, and they get to do it themselves while they wait. And then he has to leave the room, and boom, the trolley problem happens.

• 23:27Hannah Fry?

  And the trolley problem being the idea that, the question, normally theoretical, but apparently not in your case, of whether you, there is a trolley careering down a track and is set on a, on a path where it's going to kill five people, or whatever it might be, and you have the choice to pull a lever to redirect the trolley, the train, as it were, so that it only kills one. The question is, do you do it?

• 23:55Michael Stevens?

  Yeah. So, so what would you do?

• 23:58Hannah Fry?

  So it's really, I mean, the whole point of this, this like theoretical thought experiment was to demonstrate how sometimes there isn't a clear answer to an ethical question. Because if you take the utilitarian approach, right, which is like, how many lives are saved, then, then you say, "Well, obviously you should pull the lever." You know, there's five people on, if you do nothing, and then there's one person if you, if you pull the lever. But then, I mean, then there's also like the sort of value ethics, value-based ethics, which says, "Okay, but the murder, you are effectively murdering somebody because it's your intervention which is choosing somebody's death." You're choosing to intervene in a situation and with the the person's death is a direct consequence of that.

• 24:41Hannah Fry?

  I personally, I don't know what I would do in that situation. I think I would really, I think I would struggle to pull the lever, if I'm honest.

• 24:48Michael Stevens?

  Yeah, it's a struggle because, yes, if I pull the lever, then only one person dies, not five. But they died because of my action. I feel a lot more responsibility over it. I've got to talk to that, you know, person's family and say, yeah, they would have been okay if I hadn't have done it. I did save five people, but what had never been done was testing it in real life. If you actually put people in that position. So there were CCTV cameras broadcast all over this switch room, so you could see the tracks. And you could see that a worker went on to the side track while five were working on the regular track. And the authority figure, right, the guy who's employed to switch the tracks has left.

• 25:32Michael Stevens?

  And these alarms start going off, like person on track, train approaching, train approaching, what do you do? And as it turns out, um, people don't do anything. They freeze. There's there's fight or flight, but there's also freeze, and that is the most common uh behavior that we saw. Now, we had to have an actual psychiatrist on set to debrief people, to tell them everyone's okay, this was all not real. And the decision you made is not something that should bother you. You know, you really helped science today. Because people were really broken up about the fact that they did nothing. And we needed to make sure, and we followed up with them a couple of weeks afterwards. Because you don't want to traumatize people into thinking, I'm the kind of person who wouldn't pull the lever.

• 26:17Michael Stevens?

  I allowed five people to be killed instead of one. So it's a it's a really serious thing.

• 26:23Hannah Fry?

  But that's it. You're learning, you are learning something about yourself.

• 26:26Michael Stevens?

  You're learning something about yourself. And so we, we had to sit down and tell every person afterwards, you know, first of all, obviously, everyone's fine. Those are all actors. You were watching pre-recorded segments where no one was in danger. But the decision that you made is is uh the the right one. You know, there there is no decision that is fair, and to put you in that position was not fair. So you shouldn't leave thinking, oh, I did the wrong thing. But that wasn't the scariest episode for me, because I just got to watch people do it. Um, for me, the most fear I felt, it wasn't when I went to Peru and drank ayahuasca with a shaman in the middle of the rainforest.

• 27:09Michael Stevens?

  It was a experiment we did in partnership with Philip Zimbardo, the guy who was behind the Stanford Prison Experiment, where a bunch of college students were taken in during the summer and some were assigned to be guards and some were assigned to be prisoners. And they started treating each other so badly, like physically, abusively, that he had to end the experiment. And he was like, holy cow, if you give people authority and no oversight, they just abuse it. Um, it's a famous experiment, which we did a whole episode on. But we also did one on how to make a hero. And we wanted to test if people would truly become a whistleblower. If we put people in a situation where something was being done that was wrong and it was up to them to stop it, would they?

• 27:54Michael Stevens?

  If you ask in a survey, ninety-five percent of people say, of course, I would come forward. But in real life, it's a lot more complicated. And so we rented out a wing of a psychology department at a university in Los Angeles and posed as real experimenters. And we were bringing in, um, people to place phone calls to get us, um, subjects for the experiments. And we told them, you know, we're, we're looking at isolation. We're going to put people in isolation for ten days. Now, in the show, I had done three days. And that is around the maximum where someone starts to, to lose their grip on reality. There's a lot of anxiety and fears and, and also just depression, feelings of your life isn't worth it.

• 28:39Michael Stevens?

  And we told this to these recruiters and we said, yeah, it's really dangerous. Um, you know, here's a list of all the, the things that could go wrong and, and, and all of the like mental problems that could be caused by it. But it's important for science that we do this. And during the informative sessions, like half of the people in that room were Confederates who worked for us. And that was for part of later in the experiment. I also receive a phone call at some point during the orientation where I'm told that the experiment has not been approved by the university's ethical review board and that it cannot continue.

• 29:21Hannah Fry?

  So at this point then, the people who you are, who are on candid camera effectively, they, they know that this is not good. And not only that, is not approved.

• 29:32Michael Stevens?

  It's not approved. And they overhear this conversation because part of it's on speakerphone and then I switch it. And then I say, look, you know, I'll deal with this later. Like, we need to, we need to start doing this now. And every single person agreed to go ahead and phone bank for me to get recruits. And we had them call actors who were trained to ask, like, is this safe? And the recruiters just like, they worked for me. They lied and they said, oh yeah, no, this is, this is really safe and you're going to be fine. And it's going to be like a vacation. And um.

• 30:10Hannah Fry?

  They actually lied or they can see, I mean, were they like, I guess there's like a spectrum of lying, right? Like, were they just sort of concealing and saying they didn't know? Or were they actually lying?

• 30:21Michael Stevens?

  Most of them didn't directly lie. There were some who were almost happy to say, yep, this is like probably even good for you. Others, they lied in really interesting ways where they would say, they would be asked, what are the, what are the risks involved? And they would say, well, there's nothing toxic. There's no electric shocks. They, they just mentioned true things that weren't a problem to avoid mentioning the actual known problems of forced isolation. And we then had our Confederates come in and, and say, hey, I'm starting to feel bad about this. I don't think we should be doing this. To give the real participants an opportunity to say, yeah, I'm leaving, or I'm going to

• 31:06Michael Stevens?

  make a phone call. Right? And this was all filmed on hidden cameras.

• 31:10Hannah Fry?

  How many of them did? How many of them said that they wanted out?

• 31:13Michael Stevens?

  None. Still, no one, no one said anything. They just said, well, you know, it's what we're hired to do, basically. And then we had a woman come in to the rooms where they were, the cubicles where they were doing the phone calls, who said she was from the ethical review board and wanted to know what they were calling about. And they all confessed that it was for the experiment involving isolation. And we did this for two days, and only one person agreed to go on record accusing me of violating the ethic review board's decision. Everyone admitted that they were doing it and that it was wrong and that they felt bad doing it, but they just wanted to not be a part of it.

• 31:58Michael Stevens?

  First of all, there's a million things going on here. Was it loyalty to me? Was it dedication to the job they were hired for? The most common rationalization was that it was important for science that we do this. And that was also what Stanley Milgram heard the most from his participants when he, many decades ago, asked people to administer electric shocks to participants that weren't real, but they thought were real. When asked, why did you go ahead and like, do what the experimenter said and shock people so badly? They said, well, it was for science. It was for learning. It was worth it.

• 32:36Hannah Fry?

  Hmm. I mean, the, the, the background of that Stanley Milgram experiments is, I mean, darker still. It was after the Nuremberg Trials when Nazis were accused of participating in this horrific moment in history of participating in the deaths of millions of people. And, and people's defense was, well, I was just doing my job. And the Milgram experiments were to say, you know, how far will people go? How far will people harm each other if they're told to do so by somebody in a white coat and a clipboard? And it turns out, very far.

• 33:10Michael Stevens?

  They'll go very far, even for something as simple as like a minimum wage phone banking job to recruit test subjects. It's, it's almost like it's hardwired into us to be loyal to the job and do what we are told by authority. And in a lot of ways, I think the guilt can be diffused onto the system that's asking you to do it. Look, I'm just a small part in this. Like, it's not really up to me. Um, I don't want to lose my job. I don't want to get in trouble from my employer. So I'll just go ahead and tell people there are no known risks. And everyone did it. It was scary

• 33:49Michael Stevens?

  for me because I had to be the unethical experimenter. I had to answer the recruiter's questions when they said, well, when are you going to tell people that this is dangerous? And I'm like, oh, we'll debrief them afterwards on the known risks afterwards. And I had to pretend like this didn't bother me. And I want to be liked. I think it's part of being a YouTuber. I just am a people pleaser. And I really, really had a hard time psychologically with

• 34:25Michael Stevens?

  two days of being evil, but then having no pushback. Only one person ever pushed back, and never to me. They told the, the authority figure, my boss, who, who showed up, they told her, yeah, he shouldn't be doing this. And yes, one person said, I will go on record and say that I did this and that I was told to do this.

• 34:51Hannah Fry?

  It does. I, I wonder whether we should do a whole episode on that, that Milgram experiment and talking about this sort of tendency of humans in, in more detail. Cause I think that the research on it is absolutely fascinating. And it feels quite dark in a lot of ways that like, that actually, once you, once you have that intersection of like moral responsibility, but with um, sort of financial reward with like societal expectation with like systems and norms, actually, we really do struggle to, to buck the trend and stand up. I mean, it reminds me quite a bit of the bystander effect.

• 35:26Michael Stevens?

  Yes.

• 35:27Hannah Fry?

  Which is, is, is, is this idea. I mean, it's not quite as bad as um, uh, I think the very, the, the, the first sort of tellings of the bystander effect made it sound really horrific. Cause there's like this, this um, paper in the 1960s that says, somebody was stabbed to death in New York and 38 people saw it and nobody did anything.

• 35:46Michael Stevens?

  Kitty Genovese, yeah, a real murder with, with witnesses all around and not a single person. Called the police or intervened?

• 35:56Hannah Fry?

  But I think in the, over time, actually, that, that idea of thirty eight people watching on was a little bit of an exaggeration. And I think that a couple of people had actually called the police. It was sort of, it was a bit of an exaggeration by journalists. But you do see this bystander effect in the psychological experiments that you're describing, where you get people. In particular, when you have, um, smoke filling in a room and actors that are not reacting. People sort of assume that it's not really their problem. Or you have some students who are sort of sitting in a room and over an intercom, they hear the sound of somebody else having a seizure or, or crying for help or something and, and very, very few people will intervene. But it's sort of like people can reason, um, reason that this isn't their problem, that there's somebody else who will step in and fix it.

• 36:41Michael Stevens?

  Yeah, uh, the, the seizure one, I remember an experiment where people were doing some task that was obviously just a filler task over headphones. The, everyone was in their own little cubicle and they heard the people they were working with over headphones. And, um, in, in one condition, there were like four people all listening together and talking together. And then the other people were alone with just them and one other person. And if the other person they're listening to faked having a, a seizure or a heart attack, the other person listening immediately got up and went for help. But if there were, if they believed there were four people on this line and one of them had a heart attack,

• 37:24Michael Stevens?

  they would just keep sitting there for a while because surely someone else is going to do something.

• 37:29Hannah Fry?

  Right. The thing is, is that, I mean, in these experiments, that sort of, because it's a lab setting, because it's sort of a constructed setting. When you watch back videos of genuine disasters, right? So, so real emergency situations, kind of real high stakes, um, scenarios. Actually, I mean, you often do see people who step up. And I think that the, the original idea of the bystander effect is that the more people that there are, like on your phone call, the more people there are, the less it's my problem to do something. Whereas I think in situations where you have, I don't know, like a, someone

• 38:03Hannah Fry?

  Wielding a knife, for instance. Actually, the more people that there are, the more likely it is that people will step in and and try to mount a response. It's much less scary when you feel as though there's sort of safety in numbers. So it's maybe not quite as depressing as sometimes the telling of this, but there is still something in there, though, right, of like personal responsibility versus collective responsibility. I also wonder whether there's like a international dimension to this. Um, the trolley problem that you described right at the beginning, one of the most fascinating experiments that I've seen done on the trolley problem was in the sort of the early excitement about driverless cars, maybe around twenty eighteen or so.

• 38:42Hannah Fry?

  There was a group of scientists who set up a uh an online game where you could go and play the trolley problem with a driverless car, but it would give you lots of different options. So your driverless car could run over five people or one person, the traditional version. Or it could run over a couple or an old granny or a cat or a mum and a baby and so on and so on and so on, and would present you with these problems. And what was completely fascinating about that was the the breakdown of how different cultures valued different things. How how some cultures, particularly in Japan, really cared a lot about older people, um was sort of would prioritize them right at the top. Whereas other cultures, the western cultures, for instance, um you know, cared about children much more. Everyone cares about cats.

• 39:27Hannah Fry?

  Um, that's a, I think the other thing that that came on there. But um we should definitely do some episodes digging more into your psychology past.

• 39:36Michael Stevens?

  Well, yeah, because there are just so many factors. Yeah, people in groups can be better, but they can also be worse than they are alone. And what factors cause it to go one way or the other, we're still learning about. And we also still have open questions about the hypotheticals themselves. How valid are they? Because i- i- in a lab setting, it's very different than real life. Um, if you're programming a

• 40:02Michael Stevens?

  Autopilot car to, you know, favor young couples with a baby over old people. Is that really a real choice in real life? Because in real life, what the car will do is it will stop itself. It will drive off the road. It'll crash itself into a wall. Like, there's always some other option that isn't the simple this person or that person.

• 40:25Hannah Fry?

  I always thought it was really interesting how, if you're following the Charlie Problem logic, you want the car to crash itself rather than crash into people. But who's going to buy a car? Who will buy a car that will crash and potentially hurt the people driving it rather than the other people instead?

• 40:41Michael Stevens?

  Exactly, yeah. Yeah, we haven't talked about the train. What's it carrying? What if it's got, you know, 12 people on it?

• 40:50Hannah Fry?

  What if it's got a million embryos on it?

• 40:52Michael Stevens?

  Hmm, mhm.

• 40:55Hannah Fry?

  Actually, Immy, one of our producers, she's, she's just pointing out that there's this, this idea of inflicted insights, that, you know, the, the idea that there's, there's, there's trauma to learning something about yourself that you can't unknow, and that psychologists really started to discuss this a lot after the Milgram experiment.

• 41:12Michael Stevens?

  Inflicted insight, what a great phrase. Yeah, we, we encountered that so often in minefield, and I encountered it personally. Like, the reason I disliked How to Make a Hero was that I learned how easy it was to get away with bad stuff, right? I think we live our lives thinking, oh, I couldn't do that, I'll get caught. But then here I am, literally being an evil, manipulative scientist, and everyone's just eating it out of my hand, like, yeah, of course.

• 41:40Hannah Fry?

  It is interesting, that idea that being powerful and evil made you feel uncomfortable. Sometimes I do this thing where I'll like have a day or two where I will deliberately not get out of the way of anybody when I'm walking down the road.

• 41:53Michael Stevens?

  Hannah.

• 41:54Hannah Fry?

  Have you ever tried this?

• 41:55Michael Stevens?

  No, I'm not a sociopath.

• 41:59Hannah Fry?

  Like go down Oxford Street or something like a really, really busy, busy road and just like, I'm not getting out of the way. And everybody does move around you. It's like you feel so powerful and so evil and I can't keep it up. But it's, it's fun to do for like a moment and then, you know.

• 42:15Michael Stevens?

  I think it's probably a good lesson that, yeah, we are a lot more powerful than we think and allow ourselves to be, maybe for good reason, but it's fragile, that the barrier between the two.

• 42:24Hannah Fry?

  Well, there you go. We've, uh, we've learned about some of the scariest things on the planet there, then Michael, which is ourselves. Um, so if you've got any questions that you would like us to answer, you can send them in at [email protected].

• 42:39Michael Stevens?

  And you can join our newsletter at thereestis.com/science.

• 42:44Hannah Fry?

  We are going to be back next Thursday with another edition of Field Notes and on Tuesday with our normal episode. Um, until then.

• 42:51Michael Stevens?

  Stay curious. Bye bye.

• 43:06Speaker 06

  There we are getting a statement from number 10 on that flight with 350 passengers on board.

• 43:15Speaker 07

  The Great Game, Strategic Struggle Between Britain and Russia.

• 43:22Speaker 08

  We assess, uh, Prime Minister, with high confidence, it was Russian.

• 43:28Speaker 09

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