The Infinite Monkey Cage - Risk

Episode Date: November 18, 2013

The Infinite Monkey Cage returns in the first of a new series and turns its gaze on the science of risk.Professor Brian Cox and comedian Robin Ince bring their witty and irreverent take on the world to a programme all about the science of risk. Together with guests David Spiegelhalter, Sue Ion and former Goodie, Graeme Garden, the team explores such questions as: why is seven the safest age to be? Should badgers wear bicycle helmets? How safe is nuclear power and how worried should we be by the threat of asteroid impact? Producer: Rami Tzabar.

In our new podcast, Nature Answers, rural stories from a changing planet, we are traveling with you to Uganda and Ghana to meet the people on the front lines of climate change. We will share stories of how they are thriving using lessons learned from nature. And good news, it is working. Learn more by listening to Nature Answers wherever you get your podcast. Hello, I'm Robin Ince. And I'm Brian Cox. And welcome to the podcast version of the Infinite Monkey Cage, which contains extra material that wasn't considered good enough for the radio. Enjoy it. Hello, I'm Brian Cox. And I'm Robin Ince. And this is a brand new series

of the Infinite Monkey Cage. And with a big format change, there will be no preamble. We're just going to get straight into the show. I can't talk about physics. No, you can't. Well, you may be later on. Anyway, a muon or a gluon, if you're lucky. Today, we are going to be discussing risk. Someone who was brought up in the 1970s, I know all about risk because we were brought up on health and safety films. We knew that the Grim Reaper hung around near puddles.

Frisbee playing near electricity was highly dangerous. In actual research, this show, one that I'd never remembered, there's a one form which goes, a rug on a polished floor? You might as well be putting down a man trap. At this moment, I'll just go... And he'd only just come back from hospital. But anyway, we are going to be seeing where the risk has changed

from those terrible days of the 1970s into the 21st century. So how can we combat the alluring simplicity and melodrama of anecdotes with the nuanced but occasionally complex world of fact? Yes, he did put that in caps lock, just in case you're wondering. Is this even possible, or are we storytelling creatures forever doomed to value opinion over statistical evidence? Problems caused by our misperception of risk are not just confined to our everyday existence,

they affect government policy decisions through the unfortunate conduits of democracy. And at this point, yes, the audience draws, you would like every single decision made by scientists? Yes. Is it safe to secure electricity supply using nuclear power or wind? Is it safer to travel by rail or air? Is it just safer to stay at home and do nothing? No, it's not, by the way. My wife polishes the flowers. So, to help us understand risk and our perception of it, we are joined by three distinguished guests. David Spiegelhalter is Winton Professor of Public Understanding of Risk

and co-author of The Norm Chronicles, stories about numbers and about danger. Dame Sue Ian is former materials scientist and technical director of British Nuclear Fuels Limited and is one of the country's leading nuclear fuel experts. And Graham Garden is one of the country's most dangerous banjo players. And this is our panel. Graham, we'll start off with you. The goodies in the

1970s, they were famous for your incredible stunts that you did. Did you ever kind of worry about the risk? What do you think is the most ridiculous stunt that you attempted? Well, yeah, of course we did worry about the risk? What do you think is the most ridiculous stunt that you attempted? Well, yeah, of course we did worry about the risk. And I suppose the most dangerous one was the Buster Keaton gag that we recreated of a house falling down. Not just one Buster Keaton, but three of us standing so that the window frame just fell around us. And they told us that the front of

the house which fell on us had to be very heavy because then it would fall in a straight line if it was light it would drift and waft down and a bit unpredictable they scratched a little square on the floor where they reckoned the window was going to end up we had to run in stand there a moment, at which point they would drop the front of the house on top of us. And just as the house is about to come down, you do look at the floor and think, is that the right little bit of scratched earth that I'm standing on? Luckily, we survived. My theory is that anyone can do a stunt once.

People have said to us several times, any ideas for doing the goodies again? Apart from the fact that we're all too old, I doubt that you could make them anymore because of health and safety. You know, you have to fill in a risk assessment now for every show that you do. The risk assessment would be about three times as long as the script. David, is this true?

It's a general perception that there's a health and safety culture now, so therefore the world is a safer place to be. Let's say Britain is a safer place. Is that true? It is true. It is true. When I was born, about 1,000 kids a year were killed on the roads every year in the country. Absolute carnage, even though there are far fewer cars. Now it's down to about 50 a year, which is terribly sad, but that's a 95% reduction. It must be odd speaking up for health and safety,

but since the Health and Safety Act of 1974, I think 80% reduction in deaths at work. So, you know, these things have worked. It's amazingly safe. The nice statistic I like is that, you know, to be seven years old now in this country is the safest that anyone's ever been ever in the history of the planet. Only one in 10,000 will not make their eighth birthday.

It's quite extraordinary. But after seven, it starts going inexorably... I can't say that. Up and up. Amazing. And it was observed 200 years ago by this guy called Gompertz that every year we get older, our risk of dying before the next birthday goes up by 9%. And that's just a rule of our bodies.

It's an exponential growth in your annual risk of death, which is known as the force of mortality, which is a lovely, lovely word. The force of mortality goes up by 9% every year. There is this bulge between about 15 and 25 due to sort of idiotic behaviour of young people. But after that, it just carries on going up between 70 and 95 or so.

So that means every eight years, your risk of dying doubles roughly. And as a professor of public understanding of risk, some people might think you walk around absolutely paranoid and scared to death. So do you do dangerous things? Are you just going... I cycled on a Boris bike to this recording. I didn't wear a helmet. And so that's...

I knew it, I knew it! It's always the thing. There's two, yes, things you shouldn't mention in an audience. It's bicycle helmets and badgers. Anyway, I'm not going to mention badgers, but I am going to mention bicycle helmets. The point about bicycle helmets, if you do fall off your bike, then it's probably beneficial to have a bicycle helmet. The crucial thing is whether encouraging people to wear bicycle helmets. The point about bicycle helmets, if you do fall off your bike, then it's probably beneficial to have a bicycle helmet.

The crucial thing is whether encouraging people to wear bicycle helmets actually then stops people cycling to some extent and that this means there's a reduction in public health because there's a ratio, maybe 20 times the benefit of cycling compared with the risk of cycling. And it depends how you cycle. I'm a pootler. I just pootle along slow. I don't want to get there fast.

I'm like a cyclist in I just pootle along slow. I don't want to get there fast. I'm like a cyclist in Denmark or Holland, where nobody wears helmets. Whereas other people, and you can see them in London, are, you know, lycra, helmet, head down, like that. And they should wear a helmet. Actually, they should wear full padded body suits. Because, you know, they're really risky. In their car. Yeah.

So if you kill a badger by beating it to death... ..using a bicycle helmet, I presume they cancel each other out. Is that kind of that reaction? Well, what this really shows is that we all have a huge emotional investment in our attitudes to risk. It's impossible, really, to take a rational approach to it, because our feelings inevitably come into it.

We either like things or we don't like things particularly it's known as the affect heuristic the psychologists have labeled it shown it very clearly that certain things we don't gm foods we don't like them fracking we don't like them radiation we don't like it are except for having a ct scan and then we quite like it 25 years ago top of the fear along with you know nuclear and things, was microwave ovens. But then we decided they were quite cuddly after all, and now we like them. But, Sue, the nuclear industry is an interesting, obviously a counter-example to this. You're talking about technologies becoming accepted,

the fear diminishes as the technology becomes more mature. But in terms of nuclear power, if anything, it's perhaps the reverse, isn't it? Yeah, I mean, nuclear energy is one of the ones where the fear, emotional fear in quite a lot of people, outweighs any evidence in terms of facts that might tell you that it's actually safe. So, you know, the emotional reaction to nuclear energy is something that has to be factored in very carefully

in trying to take it forward. But how do you combat that emotional reaction? Because I suppose the more scientific approach, if you like, would be to just provide some facts. Yeah. I just think that in terms of being able to communicate the issues and trying to get things across and be seen as reasonable people as much as anything else,

that we have to try a lot harder. I mean, there's a huge amount of myth associated with radiation. People wouldn't think twice of having a CT scan to check out whether they were healthy or not, and yet the radiation effect from Fukushima, right up close to the site, is no different from having a CT scan. And yet, you know, you wouldn't think that that was the case

from all the media storm that resulted around it. It's the fear, I suppose, of catastrophic failure that dominates in people's mind, isn't it? I suppose the low-level leaks, although they're headline-making, especially in the early days, let's say, wind scale and things, but it's more this idea, this Chernobyl-style meltdown of a reactor that dominates people's fear, isn't it? Yeah, that's true, but even, you know, the Chernobyl-style meltdown of a reactor that dominates people's fear, isn't it? Yeah, that's true, but even the Chernobyl-style meltdown

caused handfuls of deaths, not large numbers of deaths, and that was the people who were dealing with the immediate crisis at the time. The bigger health effect is caused by the evacuations of large numbers of the population around both Chernobyl and places like like fukushima the health detriments the people in japan is massive but it's nothing to do with radiation it's all to do with the fact that you've had to evacuate tens of thousands of people so the health detriment is heart attacks alcoholism suicides depression anxiety generally from being

displaced from your home so it just ramps up the fear that people have you know oh my goodness they've told me to move away from my home so it must be really dangerous and so it just self-perpetuates and facts bear no relation to reality on the ground you started in the in the nuclear fuel industry in 1979 is that right which yeah which would have been the same year at three mile island i'm not linking the two, by the way. But I wonder, was there, before Three Mile Island, which of course was an enormous front page news story, before that, was there a reasonable kind of rosy attitude to the nuclear fuel industry, or have, because of the idea that people see, you know, they would link nuclear power, they

would think of the terrible use of things, for instance, in war, that for a couple of generations there is still a very negative feeling. Yeah, I mean, there's a huge difference between generations and what they think about nuclear energy. Three Mile Island was interesting because a lot of the reaction to Three Mile Island wasn't to do with the Three Mile Island incident itself. It was to do with a film called The China Syndrome that came out the same year, a very, very popular film starring Jane Fonda

that was about a nuclear reactor melting down and being a global catastrophe because it melted all the way to China, allegedly. That film had a massive impact on a massive audience, whereas the actual incident at Three Mile Island, I mean, it was an economic problem for the utility that owned the reactor, but in terms of health detriment, none,

other than anxiety amongst people who got in their cars and tried to drive away from the site when it wasn't actually necessary. Graham, when we mentioned right at the beginning of the show that there used to be these little short films, 30 seconds long, telling you about the dangers of rugs and water, and now pretty much the whole programming in an evening could be a health and safety film. Here's an hour-long show about what happens when you get drunk in Leicester.

Here's an episode of Casualty. Look, all of these things are going to happen to you. And I wonder how you feel about the power of storytelling, whether you've ever found yourself thinking, I watched a film and afterwards I realised I was panicked over something which may well have just been a fiction and a plot device. There are lots of movies that make you worry a bit. There's one called Contagion.

Is that a recent one about an epidemic, a sort of flu epidemic? Independence Day was a bit scary. I think a flu virus is a little bit more likely than a gigantic extraterrestrial spaceship. Ah, well. Oh, you're going to disagree on this one! Yeah! But, yeah, no, there are films.

I mean, I think the sad thing is that most people get their facts about science not from scientists. They get them from the newspapers and the media, who've always got their own agenda, which is usually to scare us. David, in your book, you mention a particular newspaper headline where the misconception is based on a misunderstanding of statistics. I think it was a Daily Express headline. Daily fry-up boosts your cancer risk by 20%.

20%, which sounds frightening until you dig down into what those statistics actually mean. Yeah, that was a lovely example because it shows the communication in terms of relative risk and it's been shown as good evidence that this inflates the impression of how important something is. When you deconstruct that story, it's about pancreatic cancer, which is a horrible cancer, but fortunately very rare.

About one in 80 will get it. So what they're saying is that if you eat this bacon sandwich or something every day, every breakfast, then your one in 80 risk is increased by 20%. Take 400 people. Well, that one in 80 that's five so five of them sadly will get pancreatic cancer during their lifetime now if all of those 400 all stuff their gob every morning with a great big greasy bacon sandwich that five would increase by 20

which means going up to six so the one extra out of 400 people stuffing their faces with a bacon sandwich if they ate a fry up every single day of their life they got to eat it can you imagine it and so told in that way because it's complete non-story it wouldn't get me reach a headline it wouldn't get any coverage at all and so the framing of the way in which the story is told is really important and newspapers use a negative frame for their story all the time rather than a positive frame. There's a lovely example where some scientists had discovered a gene which, you know, it wasn't that common, but in 10% of people it reduced their risk of high blood pressure.

That was really good. But it was a very tedious story. It didn't get any coverage at all until a brilliant press officer rewrote it and said, oh, that means that 90% of people have a gene that increases your risk of high blood pressure. Wow! And that literally went round the world, headlines, huge amounts of coverage.

The food stats one, though, is one that, you know, applies in the nuclear sector too, in terms of them wanting to make sure that in an emergency situation like Fukushima that people don't inadvertently eat things that they shouldn't. So they apply very, very, very low levels. And so people automatically assume that the low levels are danger levels when they're not, in fact. You get levels of radiation in food.

That's correct. So you'd have to eat three tons of the stuff, a single person, over a five-month period to get the same as a CT type scan. person over, you know, a five-month period to get the same as a CT type scan. So, you know, by putting the limits so low, people start to become frightened of what is an inconsequential number. There was a scary story in the Daily Mail. I know that comes as a shock, which certainly had me worried about these killer hornets. I don't know if any of you saw it, but there are these killer hornets about the size of your thumb if you've got a small thumb and they're in in china rampaging across china and they've reached europe and they're on their way to britain in china they've killed 42 people now 42 out of one and a third billion

i'll take those odds david there's a so there's a unit. We begin to try and quantify risk. There's this unit that you use, the micromort. So could you explain that? Yes, I wish I'd invented it, but a guy in Stanford did years ago. And it's a one in a million chance of dying suddenly. So one in a million is quite a nice unit. It's the same as flipping a coin 20 times in a row and it coming up heads every time.

Which probably sounds quite likely to some people. Yeah, it sounds quite likely to some people. Yeah, I'll bet on that. And it's quite good because there's 50 million people in England and Wales, roughly, and 50 every day die an accidental or violent death. That's very regular. 50 are done, exactly 50, but roughly 50 a day.

So that means one in a million of us actually die a violent or accidental death every day. So a micro-remort is our daily dose of acute accidental risk that we have. And so how do we spend our micro-remort? And so you can look at various activities which you do. 300 miles in a car is about that, about 20 miles cycling, about 7 miles on a motorbike. You go scuba diving, that's about 5.

Anesthesia, that's about 10. These are the things that get government scientific advisors into trouble, aren't they? Because I think in your book, there was a statistic about ecstasy, which famously got David Nutt into trouble. I think that was two micromorts. Yeah, it's roughly a tablet. We reckon it's about

one or two a tablet, roughly. And he was comparing it with horse riding, which he called equacy. And he was saying that you know, he was making a bit of a point which got him into enormous trouble, that these are roughly equivalent micromort risks. I think, though, it's a completely valid comparison

because these are voluntary activities undertaken by, generally by young people, for fun. It's just that one is wholesome and the other is considered not wholesome. And Theresa May did not like it. And she backed it up with all manner of opinions. Can we just... We have to balance it somehow.

And add Milliband as well. Carry on. I actually want to go back to nuclear power a little bit and talk about the strength of anecdote and why, with what's happening in Fukushima, in Germany, they're actually going to close down all 22 of their nuclear power stations by electricity from France,

which I imagine is a shocking thing for the Germans. Also because it's 80% nuclear, isn't it, France? Yeah, France is roughly 80% nuclear. So why do you think they've had this reaction? It seems, in many ways, quite an unusual reaction. Yeah, I mean, the Germans are quite weird, actually. I mean, not... I didn't really mean it to come out like that.

Do you know what? Your phrasing was fine, but the applause may well change the way the agenda was taken. You know, for a nation that is traditionally seen as, you know, one that is analytical, you know, very sound engineering, good scientific bases, etc., it was an unusual reaction. Largely politically driven, but also because in Germany, nuclear energy, there has always been a greater suspicion, a greater dread amongst German people about nuclear energy than there has been in other countries like ours or France or much of the rest of Europe. So you're quite right. As a consequence, Germany is building gas stations and has increased its gas take from Russia.

It's building more coal stations and has increased its coal take from Poland and Eastern Europe. And it's importing nuclear electricity from Russia. It's building more coal stations and has increased its coal take from Poland and Eastern Europe, and it's importing nuclear electricity from France. So Germany's ability to meet its green targets is actually severely impaired. Even though it's done very well with wind energy and with solar energy in terms of its renewable obligations, it will find it extremely difficult, if not impossible, to meet its targets for carbon reduction. And then I suppose, David, difficult, if not impossible, to meet its targets for carbon reduction. And then I suppose, David, climate change, you often hear the argument, we should wait and see from a certain vocal minority, I suppose.

You know, well, let's just see, because it will damage our economy if we do something about it. Whereas you rarely hear wait and see from opponents of nuclear power, who say, well, let's just wait, shall we, until one does what we think they do, which is the big mushroom cloud come up out of it, which, of course, that doesn't happen. Sue, I know that doesn't happen. But there is this long-term risk

seems to generate this overuse of a precautionary principle, as it were, to say, well, let's just wait, shall we? Yeah, I mean, the precautionary principle started off as a very reasonable thing, I think, in the idea that we shouldn't have to wait till we certain there's harm before we try to do something to mitigate it and that would be the sort of principle that people now would use in in favor of acting about climate change but it's sort of morphed into something a lot stronger now which is that you shouldn't do anything unless you can prove it's safe and that sort of strong version, which is almost embedded in EU legislation, can be overused by anyone who's got a fear that a technology or any sort of action will have a damage in the future.

Well, Graham, in this show we've talked a little bit about climate change, we've talked about nuclear fuels, we've talked about badges and bicycling helmets, so there is a high percentage chance we'll be getting a lot of complaints. And I wonder, sometimes the way that you can actually view public opinion is by what you get the most complaints for. It's things that people feel very passionately about, and we see that in the world of risk and we see that in the world of danger. And I wonder if you ever see that in the years that you've been broadcasting, where you think, I thought what we'd done there was perfectly fine, there was nothing there to kind of insult people or wind people up,

but because we dealt with that issue, whether it's on the radio or television, you see a fury and you see the opinion coming out. We did a couple of shows. We did one show about South Africa, which was basically attacking the idea of apartheid, which was going on at the time, and we changed it to apart height,

so we all went out to south africa and bill being short was was a second class citizen and he was uh he and all the jockeys were made to do the menial tasks looking at it now it looks a little bit racist it was done with totally uh honest intentions um and uh very much the atmosphere has changed, the attitudes have changed the words that were used then were common parlance totally unacceptable now I know you have the unenviable task of advising politicians

from time to time so you have to interact with these people but it seems from my perspective there seems to be they feel it's legitimate. I mean, we've seen it recently in the news from various politicians to say, well, no, but the electorate feels this.

You see it from newspapers as well. You see in defence of editorial positions, well, our readers care about this, they think this. Yeah, I mean, you do meet it a lot, and you're quite right. You sometimes wish that life could be scientific and not political, but it's not that way. But persuasion of least worst options is sometimes where it gets to. So, you know, you're talking about nuclear energy and the energy mix,

and you talk about the risk of the lights going out. So the lights on becomes more of an issue than whether they like nuclear energy or not. I mean, presumably, though, you said reinvestment in the nuclear baseload. Presumably it's any baseload. So we could reinvest if we wanted in power stations. One of the biggest challenges now is to replace the whole of the UK's energy infrastructure, refresh it and renew it.

I mean, we're a lucky generation. You know, we live on the back of investments made in the 1950s and 60s. And there was only 50 million of us in 1950. You know, there's an eye on 70 million of us now so you know we need we need more infrastructure than we had in 1950 so we need it all refreshed so that's why you know sometimes statements like those made by Mr Milliband last week about freezing electricity prices you know are not necessarily the smartest things to do because somehow we've got to pay for you know reinvestment in new power stations of any sort,

whether they be wind or new fossil, gas and coal, nuclear, new grid. We need the whole lot renewed. And I suppose this is the sort of glacial rate of decision-making in our energy sector. It's, I suppose, a symptom of this lack of, I suppose, the inability to get to grips with the risks of different uh power generation strategies the the risks of not doing anything there seems to be decision making is grinding to a halt because there's no clear i suppose clear mandate from the facts as it were yeah i mean that's absolutely right brian but i mean energy policy is you know

akin to national security you know without, a nation in the 21st century has got serious problems. You know, whereas in the 1970s we could put up with the three-day week and roll in blackouts and brownouts, we can't survive as a 21st-century society now. I mean, imagine what it would be like. No iPhone, no iPads, no nothing for a week, say. Oh, the good old days.

Roll in blackouts. Oh, no, you get your piano out and week, say. Oh, the good old days. Rolling blackouts. Oh, no, you get your piano out and start doing all that and you get your gun stuff again. No, I don't like that. Oh, no, thank you. It's a good point, Graham, isn't it? Because I remember that. I was quite young, but I remember being,

I was five or six or something, I remember being excited because you had to get candles out and light them. But it is true. It's almost impossible to imagine that being accepted now, to have a rolling programme of blackouts where people have to sit in the house without their TV on. People actually die when you've got blackouts. You know, people die in blackouts.

I'm not glamorising it. He's a very narcissistic man. I'm a bloody talking candle. This one's scented. But it has changed. The bourgeois, I've got the bourgeois kind. I've got much better candles now. Wonderful ones from South Africa.

I live in the country, and we... Not so bad lately, but for some years, we've had fairly regular blackouts, and very often leading up to Christmas, which is very tedious. The last one we had... Yeah, it is quite sort of cosy and exciting. It's like snow. It's nice for the first day. And after that, it's a real pain.

So if you have a blackout that lasts for more than an evening, it's horrendous. But, I mean, in terms of what it would do to our electronically-based society now, it would be terrible. Oh, blackout as well. The worst one's when you get a blackout halfway through a game of charades. That happened to me with Lionel Blair once, but Graham, don't tell that story.

So, overly niche reference there. We've got no common order. There's no overlap between our audience. There should be. It's Radio 4. They don't change. They're not going to suddenly listen to Ken Bruce. So, it would be madness. I want to talk a little bit about how do we... This is one of the hardest things, I think, for anyone like me who is quite clearly a non-expert,

which is trying to understand who to trust. When you are trying to weigh up, you know, we have an enormous media, the internet allows us to find which any anecdote we want, which is the one that fulfills the kind of needs. And I wanted to go back to someone that you mentioned in a book in terms of looking at, you know, there are times when experts fight with experts and the wrong ones kind of win for a while, which is you talk about Semmelweis. And I wonder if you could tell us a little bit of the story about Semmelweis and an idea that he came up with which could have changed lives but took a long time to actually come into practice. It's a famous story in medicine.

Really, Graham should probably tell it, because it was based in the 1840s when... Do you want to tell it, Graham? Do you want to tell it? Well, I can try. I'm sure David will correct me if I go wrong. And then it's your go after that, sir, if he stumbles. Yeah, exactly. That's another Radio 4 thing.

Ignaz Semmelweis is a hero of mine, partly because he was, in his own time, completely unsung, in fact, quite the reverse. He was a doctor in Vienna who noticed that in the hospital where he worked, women whose babies were delivered by the midwives did much better than women whose babies were delivered by the midwives did much better than women whose babies were delivered by the students and doctors and in fact a lot of those women got fever and died

and david could probably give me the the figures of it was something like 20 percent of the oh for the women treated by doctors it was yeah i think it's about 18 out of 100 yeah you mentioned you say in one week i think it's in your book I think it was about 18 out of 100 or something like that. You mention, you say in one week, I think it's in your book, in one week it was one third of people who gave birth, yes. So he thought that it may be something to do with the fact that the doctors and students were coming from doing autopsies on corpses, people who had died of all sorts of diseases, and then coming up to the labour wards to examine the women

without washing their hands in between. And so he suggested that they wash their hands. In fact, in chlorinated lime, a sort of bleach. The reason he chose that, I think, was because it stopped the smell on corpses, and so he thought whatever this particle that they were bringing with them, people didn't know about germs at the time,

might be attacked by the bleach, and so he got them to wash their hands in bleach, which they reluctantly did and cut down the mortality completely. I mean, there became no difference between the midwives and the doctors. But the doctors saw this as a terrible insult to them, and they went back to their old ways. They eventually sacked Semmelweis. He became more and more obsessed with it,

writing letters to every doctor he could think of, calling them murderers. Eventually, he became so hysterical about it all that he was put in a lunatic asylum, where about two weeks later later he was beaten up by the guards and died of an infection and he was no doubt mad as a bat and a pain in the bum but he was right and when you talk about risk the risk he took was with his own career and his health and it didn't pay off it paid off for all the women whose lives he saved,

and it was years before it was really accepted that what he suggested was the right thing to do. But, I mean, that's why he's a hero of mine, because he was right against all the odds and was never recognised for it in his lifetime. I mean, it's quite remarkable now, when we think that things are common sense and then you find out that they weren't,

to actually go, well, I can't imagine, because I'm covered in a dissected, diseased corpse and now helping this woman give birth, I can't see how the two things could be linked to passing on disease. Well, in those days... Now that seems preposterous. In those days, the doctors had a working coat, a sort of frock coat that they wore every day,

and it was a sign of sort of your experience and your seniority. The more blood and pus and bodily fluids were caked on this coat, which was never cleaned. So the more senior you were as a doctor, the more a walking hazard you were on the wards. It's interesting, David, Robin used that word common sense there, which I suppose in some sense is the problem, because people feel their opinion,

always they'll think they're acting according to their own common sense. So if you take decisions, I don't like nuclear power, I don't like GM crops, I don't like... Whatever it is, whatever controversial issue you pick, how do you begin to extract that or take that away from people and say, don't use your common sense, because we're not good at perceiving risk? Exactly. The point about Sam Weiss is that he provided the evidence.

He measured the statistics, he actually conducted an experiment. It wasn't randomised, but it was a pretty good experiment. And so it wasn't just opinion. He was showing evidence. The psychologists have got this really nice idea of, what are we trying to do when we communicate statistics and facts to people? was showing evidence the psychologists got this really nice idea of you know how can we you know what are we trying to do when we communicate statistics and facts to people and um they they they say they're trying to breed immunity to misleading anecdote which i think is a beautiful phrase you know that's what i think that's what my job is you know trying to breed immunity to

misleading anecdotes seems very difficult i mean you need things like, for example, a balanced and rational press. Oh, yeah, no. You can't expect that, because the press is there to entertain and it's there to sell newspapers, so it's always going to go for something that's new and different. So it's going to go for the one case in which something happened and won't report the million in which it didn't.

Can I ask David a question? Or anyone else who'd like to answer it uh i'd like to know if it's an anecdote or a statistic but it's the story i've heard about the sport which has the highest number of deaths during play do you know that one it's bowls yeah yeah, I have heard that Very nice Dan, do you think that is a story, an anecdote? I'm not sure, I think I have heard that before No, I think it's completely plausible It just shows that you need to correct for the age of the people taking it

Well, she bowls injuries though, is it, as such? Well, I don't know Actually, they do sometimes I've seen animosity on a lawn. Graham, we've been talking about perception of risk, and I suppose you're not a risk professional. What do you think or perceive as the greatest risk to thousands or even millions of people?

If I had to put my money on any particular horse, I'd put it on a virus, and my nightmare virus would be something like AIDS, which has a very long incubation period, with a jacket like flu, which is constantly changing and is spread by droplets, so that in theory everybody in the world could have it before they knew. For me, I think the breakdown of civilisation that would come,

I think, with, you know, energy, you know, breakdown in energy supplies. Which is a very easy risk to mitigate, isn't it? I mean, the energy supply security, it's a problem of our own making, isn't it, that particular one? Whereas pandemic flu or, you know, super volcanoes, these big ones, asteroid impact, big impact big huge risks but we can't do much about we can't it's funny asteroids is about one micromortar lifetime it's been calculated is that so we're going to get hit once every 70 million years or something like that the last

one was 70 million years ago terribly unscientific thing to say don't watch out i mean i guess for me the other one which we ought to be able to do more about and mitigate against is climate change which can cause you know catastrophic shifts in certain parts of the globe's climate so looking to the future where you can actually do something about it is something that as a responsible society we should be doing. We shouldn't be deliberately drifting our way towards something that could be prevented you know the worst thing is because this is the kind of quite a serious bit of the show and the moment you were asked what do you think could be the most catastrophic event because you're part of my childhood graham all i saw of course was a giant

kitten and doodle going through london and i was trying to remain serious but that's all i saw you've ruined my mind thank you very much to everyone much to everyone. We always ask our audience a question to get their advice and find out what they particularly feel about the world, and today we have asked them, what is your most ludicrous fear? The audience's most irrational or ludicrous fear is Lady Gaga riding a sheep around my kitchen. On my deathbed, I will regret not kissing Brian May. Yes, the other Brian. The other science hero, the more Newtonian-looking Brian. And she had the chance. These two,

I think, are linked. The first one's very strange. It says, my husband stalking Brian Cox, which is rather odd. But then there's another one here saying, Brian Cox stalking my wife. So it's just strange. That's a kind of Escher-like idea, isn't it? It's kind of just... I like that. This is, uh, what is your most irrational fear? Butterflies and frogs, not together. That's from Jill, I love that.

I'm not an idiot, not them together, separately. The chewable toothbrush. It used to be height, but now it's width. That's, uh... Fear of sunken boats and ships. Oh, I like that. They are very difficult to avoid. David, you're a professor

of risk. I still get terrified at the top of escalators that I'm going to get sucked in. Well, that is... I always have to jump off. Someone else says that. In London, when they first had escalators that I'm going to get sucked in. Someone else... I always have to jump off. Someone else says that. In London, when they first had escalators, apparently there was someone who was actually paid

to go up and down the escalator so that people would go, oh, that's OK, the escalators are safe. But some people still found it scary and apparently they then employed a one-legged man to go up and down the escalator and someone was seen standing going, I'm not going up there.

Look, that man lost a leg last time. That brings us to the end of the show. Thanks to our panel, Sue Ian, David Spiegelhalter and Graham Garden. Next week, we're going through the doors of perception with Alan Moore. We won't be coming back, which is going to be absolutely fantastic. And we have a question, of course. We always get a question sent in. And today's question is from Gavin Osborne.

And he asks, just when is all life on the planet Earth going to end? I was told it was in 4.6 billion years' time when the sun swells into a red giant, but I've recently read that all water will have dried up on the Earth within 3 billion years, destroying all life. Please tell me which it is so I can work out just how long my bucket list should be.

It's playing havoc with my planning ahead. Yeah, I was going to say we'll get hit by the Andromeda galaxy before that, we think, because that's coming towards us extremely quickly. But David is right, you know, we'll get hit by a very big piece of rock at some point, and if we've not learnt how to move them, then that would be, on average, as you say,

around 70 million years per catastrophic, potentially life-destroying incident. So the good news is it's closer than Gavin thinks. He doesn't have to wait. So there's the good news. The end of world is nigh, as it always has been, and will remain so. Thank you very much and goodbye.

That was the Infinite Monkey Cage podcast. I hope you enjoyed it. Did you spot the 15 minutes that was cut out for radio? Anyway, there's a competition in itself. What, you think it's to be more than 15 minutes? Shut up, it's your fault. You downloaded it. Anyway, there's other scientific programmes also that you can listen to.

Yeah, there's that one with Jimmy Alka-Seltzer. Life Scientific. There's Adam Rutherford, his dad discovered the atomic nucleus. Inside Science, All in the Mind with Claudia Hammond. Richard Hammond's sister. Richard Hammond's sister. Thank you very much, Brian. And also Frontiers, a selection of science documents on many, many different subjects.

These are some of the science programs that you can listen to. In our new podcast, Nature Answers, rural stories from a changing planet. We are traveling with you to Uganda and Ghana to meet the people on the front lines of climate change. We will share stories of how they are thriving using lessons learned from nature. And good news, it is working. Learn more by listening to Nature Answers wherever you get your podcasts.