Health check

Summary

More or Less: "Health Check" – Summary

Podcast: More or Less (BBC Radio 4)
Host: Tim Harford
Date: January 21, 2011
Episode Theme:
A critical look at the numbers behind health claims in the UK—unpacking media and political statistics about mortality, NHS performance, and more, plus an exploration of pseudo-statistics (like "Blue Monday"), unemployment figures, parliamentary numerology, and a book discussion on mathematical and scientific classics.

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Main Discussion Points & Insights

1. Scrutinizing NHS and Health Statistics in the Media

[00:24–08:02]

• Headline Claims: The government and media frequently claim that the UK fares poorly on health outcomes compared to other European countries, particularly in cancer and heart disease survival rates.

  • Andrew Lansley (Health Secretary): "You're twice as likely to die of a heart attack in this country as you are in France." [01:04–01:07]
  • David Cameron (Prime Minister): "We're more likely to die of cancer or heart disease... I don't think we should put up with coming second best." [01:34–01:45]

• Debunking with Data & Context:

  • Heart Disease Data: In 2007, per World Health Organization statistics, 93 per 100,000 die of heart disease yearly in the UK versus 35.4 in France. [02:07–02:46]

    • UK death rate appears almost 3 times that of France.
    • Analysis: Dr. Pete Scarborough (British Heart Foundation) explains differences partly arise from how deaths are categorised:

      "In France, they're much less likely to [label sudden death] as heart attack. They're much more likely to put that down as an unidentified cause." [03:43–04:35]

    • Other countries (e.g., Italy) show smaller gaps, suggesting reporting differences skew comparisons.

  • Spending and Outcomes:

    • Scarborough stresses that lifestyle changes (less smoking, changes in diet) drive much of the reduced mortality, more than health spending or direct healthcare improvement.

    • "Treatment is effective, but the way that you reduce mortality rates most effectively is to reduce the number of people who are having heart disease in the first place." (Dr. Pete Scarborough) [05:01–05:40]

  • Cancer Survival Rates:

    • UK historically behind places like Sweden; however, the situation is improving rapidly due to recent investments.
    • Prof. Michael Coleman:

      "We've had lower numbers of cancer specialists, less access to radiotherapy... but there's been substantial investment over the last 10 years, and I just don't think we should expect these measures... to respond to injections of money instantly." [06:32–07:24]

    • Improvement trends mean the UK is not necessarily falling further behind; in some cases, it is catching up.

• Quote of Note:

  • Prof. Michael Coleman:

    "There is certainly some evidence that trends in survival here are doing reasonably well for one or two of the major cancers, breast cancer in particular, and we're certainly not falling further behind these comparator countries..." [07:34–08:02]

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2. Debunking "Blue Monday" – Pseudoscience in the Media

[09:02–11:21]

• 'Blue Monday'—allegedly the "most depressing day of the year"—is shown to be derived from a pseudo-formula promoted for PR in 2005 by Sky Travel.
• The supposed equation lacks any scientific rigor and does not stand up to scrutiny.

  • "According to the equation in which all scales are undefined, there's no way to calculate the most depressing day of the year for people who didn't make any New Year's resolutions." (Tim Harford) [09:29–09:52]

  • The formula's author declined to appear on the programme to defend it.
• Criticism of Media:
  • Tim Harford:

    "This sort of thing distorts the public view of what science is and is a pretty poor reflection on the state of British journalism." [10:50–11:04]

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3. Unemployment Figures – How Can Unemployment Rise While the Rate Stays the Same?

[11:21–13:29]

• Listener Query: How can the number of unemployed rise but the unemployment rate remain constant?
• Clarification:
  • Media compared overlapping three-month periods (e.g., Aug–Oct vs. Sept–Nov), which is not statistically valid.
  • Proper comparison (two non-overlapping periods) shows unemployment rate did rise by 0.2 percentage points (from 7.7% to 7.9%). [13:15–13:29]

  • "If you compare the figure announced this month with that announced last month, you're comparing two overlapping three month periods, which means you'll count... the same two months twice." (Ruth Alexander) [12:21–13:07]

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4. Parliamentary Numerology – Prime Factors in the House of Lords

[13:29–14:58]

• Amusing moment as Lord Harris discourses on the prime factorization of proposed parliamentary seat numbers, mulling whether numerology played a role in arriving at figures like 600 or 650.

  • "650 is the product of three prime numbers... 630, of course, is the product of four prime numbers..." (Lord Harris) [14:11–14:58]

  • Tim Harford quips: "Multiply together the five smallest primes... you get 2,310. Too many MPs, I think for most people's taste." [14:58]

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5. Debt vs. Deficit – Government's Misleading Language

[14:58–16:52]

• Critique of Chancellor George Osborne’s metaphor about "paying off the nation's credit card":
  • Current fiscal policy reduces the deficit (rate of debt growth), but doesn't pay down national debt, which is forecast to keep rising in nominal terms for at least five years.

  • "Mr. Osborne's spending cuts and tax rises... are merely reducing the rate at which the nation's credit card bill grows." (Tim Harford) [15:34–15:49]

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6. Book Recommendations & Discussion

[16:52–25:11]

Guests: Alex Bellos, Rachel Riley

a) Euclid’s Elements of Geometry (Oliver Byrne Edition)

• Alex Bellos:

  • Praises Byrne’s color-coded 1847 edition for its visual approach, making "dense" geometry more accessible.

  • "Soft porn is geometry. I don't know about you, actually. If you look through, you know, the colours... it's really like sort of Mondrian or the beginnings of modern art." (Alex Bellos) [18:08–18:25]

• Rachel Riley:

  • Notes people learn maths visually in different ways, lauds the book’s clarity but says it’s not ‘poolside reading’. [18:42]

b) Physics of the Impossible by Michio Kaku

• Rachel Riley:
  • Finds it imaginative and accessible, approachable for math enthusiasts interested in science fiction.
  • Highlights the classification of "levels of impossibility" and discusses concepts like quantum teleportation. [20:41]
• Alex Bellos:
  • Points out the bittersweet nature, as the book rationally dissects sci-fi dreams and pronounces some impossible.

c) Gödel, Escher, Bach by Douglas Hofstadter

• Tim Harford:
  • "An 800-page long excursion into artificial intelligence, music, literature... the relationship between formal logic and artificial intelligence." [22:49]
  • Appreciates its playfulness and complexity, e.g., palindromic dialogues.
• Alex Bellos:
  • Explains Gödel’s incompleteness theorems, the role of self-reference.

  • "These sentences are these sort of self recursive, self referential... self reference is very funny if you think about it... I'd never be a member of a club that would have me as a member." [23:39–24:12]

• Rachel Riley:
  • Finds some content "quite heavy reading," noting different approaches in physics and math books. [24:41]

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7. Language and Numbers – "Times Smaller" Controversy

[25:11–End]

• Listener raises issue with phrases like "a thousand times smaller," arguing "times" implies increase.

  • Tim Harford defends its rhetorical value versus more precise but unwieldy constructions like "one thousandth as large."

  • "Take the phrase five times poorer. It can't be translated literally into a formal mathematical expression, but it's obviously the opposite of five times richer." [25:35]

• Show title discussion: Some listeners suggest it should be "More or Fewer," but Tim Harford humorously rebuffs this: "But we do believe that less is more." [25:56]

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Notable Quotes & Moments

• Highlighting Reporting Problems:

  • "What they've done is compared the latest unemployment rate figure... with the one published last month... seems reasonable enough, but wrong." (Ruth Alexander) [12:21]

• On 'Blue Monday' Pseudoscience:

  • "Blue Monday is a sort of mental virus which has infected the British media." (Tim Harford) [09:29]

• On Heart Disease Statistics:

  • "France is the lowest by a good long way... it's probably not a very fair comparison." (Dr. Pete Scarborough) [04:35]

• Wit in Mathematical Filibustering:

  • "But we can assure the noble lord, that nobody will pick up the gauntlet he's thrown down. Multiply together the five smallest primes, and you get 2,310. Too many MPs, I think..." (Tim Harford) [14:58]

• On Misleading Debt Language:

  • "It's a little early to suggest that the nation's credit card bill is being paid off just yet." (Tim Harford) [16:31]

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Key Timestamps

• [00:24–08:02]: Health and NHS statistics analysis
• [09:02–11:21]: Blue Monday myth debunked
• [11:21–13:29]: Unemployment stats confusion resolved
• [13:29–14:58]: House of Lords numerology
• [14:58–16:52]: Debt vs deficit linguistic critique
• [16:52–25:11]: Maths & science book discussion
• [25:11–end]: Language of numbers, show wrap-up

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Overall Tone and Approach

Clever, sceptical, and wry—Tim Harford and team treat numbers with a critical but good-humoured eye, debunking misleading claims from media and politicians, and poking fun at statistical missteps and numerical trivia.

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Summary for New Listeners

This episode gives a masterclass in how to interrogate numerical claims in public discourse—from health scare headlines to government spending metaphors and even to mathematical curiosities voiced in Parliament. The hosts and expert guests stress the importance of understanding context, methodology, and the limits of what statistics can really tell us. The episode closes with a lively book discussion, proving that numbers can inspire wonder, creativity, and even a sense of fun.

Transcript

[A]

Thank you for downloading this week's More or Less podcast. Here's Tim Harford.

[B]

Hello and welcome to the last More or Less of the series. We are, of course, your regular guide to numbers in everyday life. In the headlines and even in the House of Lords, we will be aware

[C]

that 650 is the product of three prime numbers 2, 5 squared and 13.

[B]

This week, we'll be asking how unemployment can both rise. And in the same news story, stay the same. We'll discuss our favourite number books with Alex Bellos and Rachel Riley. And was Monday really the most depressing day of the year? But first, another week, another reform from the Government, and this time it was the NHS and a chance for more or Less to scrutinise the facts being repeated across the airwaves and in the papers. It also caught the attention of loyal listener John Mitchell. He heard the Health Secretary, Andrew Lansley on PM earlier in the week. Cancer survival rates in some of the most common cancers.

[D]

Nowhere in England are they as good as they are right across Sweden, for example.

[B]

You're twice as likely to die of

[D]

a heart attack in this country as

[B]

you are in France.

[D]

We have deaths from lung disease that are amongst the worst in Europe, so

[B]

we do have to have better outcomes. And within minutes of this being broadcast, Mr. Mitchell emailed more or [e-mail] with his suspicions about the claim. Will the Government next be saying, you are twice as likely to die if you live in the UK compared with France? A job for more or less? I think it was a very similar claim to that made by the Prime Minister, David Cameron, earlier in the day.

[D]

We've fallen behind the rest of Europe. We spend similar amounts of money, but we're more likely to die of cancer or heart disease. I don't think we should put up with a second rate with coming second best.

[B]

Interesting one. And of course, as John Mitchell implies, if the percentage of people who die of heart disease and cancer is high in the uk, the percentage of people who die of anything else must be lower. But beyond that simple piece of arithmetic, is it really true that the UK is so far behind our continental cousins and is the NHS to blame? Wesley Stevenson's here. How's the nation's health, Wes?

[E]

Well, first, let's look at Andrew Lansley's claim that we're not doing so well on lung disease here. He seems to be correct, but he also talks about heart attacks and David Cameron in his talked about heart disease and we've been looking at the heart disease figures which are Interesting. If you compare Britain and France, if you look at the figures from the World Health Organization, the latest figures show that in 2007, for every 100,000 people in the UK, 93 people died of heart disease. In France, this figure is 35.4.

[B]

So the UK death rate, that's almost three times as bad as France. And are these the total deaths from heart disease?

[E]

They're the death rates, so the deaths in any given year. So John Mitchell's email notwithstanding, it would be possible for France to have a lower annual death rate from all causes as long as the French were longer lived. Are they not really? According to a study in 2005, male life expectancy at 50 is broadly similar at around 30 years. Female life expectancy is slightly better in France, 35 years, compared to 33 here.

[B]

So that's not nothing?

[E]

No, not nothing. It's around two, two and a half years, if you look at the actual figures. So even if you don't die of heart disease or cancer in France, it does look like something else will kill you anyway. And there actually might be an explanation for this, which also shows why comparing heart disease deaths in Britain and France doesn't necessarily tell us anything at all. I spoke to Dr. Pete Scarborough, a senior researcher at the British Heart Foundation Health Promotion Research Group at Oxford University in England.

[F]

And in most of the countries around Europe, if a doctor comes across a person who has died suddenly outside of hospital, and if they look at the body and there's no particular reason to consider any other cause of death, and if perhaps the medical records of that person indicate that perhaps they had high cholesterol or raised blood pressure, then doctors in this country are very happy to put that down and say, well, that was presumably a heart attack, so we'll call that one a heart attack. In France, they're much less likely to do that. They're much more likely to put that down as an unidentified cause death. And because of this, France has very low rate of heart disease when it has a reported rate of heart disease. If you actually look at the reported mortality rates from heart disease around Europe, France is the lowest by a good long way in the entire of Europe. So in that sense, it's probably not a very fair comparison. It's probably fair to say that France has got lower heart disease deaths than in England, but I would be very surprised if it was half as low if you looked at a similar sort of country like Italy, where we'd expect there to be around the same number of heart disease deaths as in France. Well, in Italy, there's only about a third less heart disease deaths than there are in England.

[B]

What about David Cameron's claim about public spending on healthcare compared to other countries?

[E]

Well, Dr. Scarborough thinks there's a problem here, too. He says the main factor driving deaths from heart disease isn't bad health care.

[F]

Treatment is effective, but the way that you reduce mortality rates most effectively is to reduce the number of people who are having heart disease in the first place. That's why we've got dramatically falling heart disease mortality rates in England at the moment, anyway, of changes in risk factors from the 1960s, 1970s, when they had peak numbers of present cases. We've got much lower smoking rates now than we did back in the 60s and 70s generally. We've changed our diet to reduce things like butter consumption and lard consumption to get better kind of fatty acids in the diet. And that has reduced the number of cases that are presenting and hence that's reducing the mortality cases as well.

[B]

Okay, what about cancer?

[E]

Andrew Lansley claimed that we had worse survival rates than in Sweden, while David Cameron said we'd fallen behind the rest of Europe and were more likely to die of cancer here compared to countries that spend similar amounts of money. Now, I checked this out with one of the most eminent academics in this field, Michael Coleman. He's a professor of epidemiology and vital statistics at the London School of Hygiene and Tropical Medicine. Now, he says that Andrew Lansley and the Prime Minister are right, but all they're doing is comparing a moment in time. And this doesn't take into account the trend. The number of people dying from cancer, cancers such as breast cancer in this country has fallen rapidly over the last 30 years and much faster than in other countries. And in these areas, we're not that far behind places like Sweden. Professor Coleman also thinks that comparing our current survival rates with our current or recent spending is also problematic.

[G]

It's not so surprising that our survival has been lower than in comparable countries. In Western Europe. We spent a lot less money on health service in general and cancer care in particular than those countries. We've had lower numbers of cancer specialists, less access to radiotherapy. It's not surprising that our levels of survival have been lower, but there's been substantial investment in resources, both in staff and equipment in the health service over the last 10 years. And I just don't think we should expect these measures of survival and mortality to respond to injections of money instantly. And that's the implication behind the Prime Minister's remark. These things take a long time to work their way through into nationwide effective outcomes.

[E]

So you see the trend and improvements continuing as the effect of the money that's been pumped into the health service over the last 10 years takes a effect.

[G]

Yes, I think that's a reasonable proposition. Clearly that it's also speculation and we'll have to wait and see what the data eventually show. But there is certainly some evidence that we published indeed last week suggesting that trends in survival here are doing reasonably well for one or two of the major cancers, breast cancer in particular, and we're certainly not falling further behind these comparator countries for those cancers where we haven't been catching up, we've been staying

[B]

parallel, if you like, Michael Colborne, professor at the London School of Hygiene and Tropical Medicine and of course, Wesley Stevenson. Thank you, Wes. You're listening to More or Less emails continue to pour in to More or [e-mail] about the death of Nigel Pargetta. Graham Paul wrote, if Nigel had been falling away from David, he would have been accelerating away and the tone of his scream would have decreased due to the Doppler effect. For a free fall of 40 meters, then the frequency should have decreased by some 10%. But there was no change in his tone. Very smart, Graham. Paul also titled his email Nigel's Death Faked. I think we'd already figured that one out when we met Graham Seed, the actor who played Nigel. You can of course listen to that interview via our website, BBC.co.uk more or less Now. Monday was the most depressing day of the year for people who care about silly research.

[D]

According to a British psychologist, this week is the most depressing of the year, with misery troughing on the third Monday

[B]

of January, or Blue Monday as it is now being dubbed.

[D]

Blue Monday, the gloomiest day of the year.

[B]

Probably not if you're an investment banker

[D]

looking forward to your imminent bumper bonus. The Moral Maze returns to Radio 4 at 8 o' clock this evening and here is Michael Burke.

[C]

Tell us about it.

[D]

Morning, Michael.

[B]

Good morning, Justin.

[E]

Morning, Sarah.

[B]

God knows how they measure these things, but next Monday, January 22, is statistically going to be the most miserable of the year. Can't even decide which Monday is Blue Monday. Now I realize that in the annals of statistical crimes, daft pseudoscientific equations probably don't rank up there with lying in Parliament or faking research in a peer reviewed journal. But indulge us for a moment. Blue Monday is a sort of mental virus which has infected the British media. It was originally released into the Wild in 2005 by Sky Travel, a television station which has since closed down. And for a payment of £1250, they were assisted in their calculations by Cliff Arnold, who at the time was a part time tutor at Cardiff University. Cliff sent us the formula, coloured pink and purple and formatted with a striking 3D effect, and we've been trying to figure it out. Cliff Arnold told us that the formula wasn't actually based on any empirical research beyond informal conversations. He also sent us a biography explaining that he used to live in John Lennon's former home. But that's not the only thing that makes no sense. According to the equation in which all scales are undefined, there's no way to calculate the most depressing day of the year for people who didn't make any New Year's resolutions. For people with substantial savings, the most depressing day of 2011 is actually in 2010. Each year, the Blue Monday brain burp emerges with a new champion and a new set of press releases. This sort of thing distorts the public view of what science is and is a pretty poor reflection on the state of British journalism. We asked Cliff Arnold to come on more or less and explain himself and clarify any misunderstandings we might have about his equation, but he declined. Now, here's a question from listener Sonja Rothwell, who originally got in touch by tweeting me. Imharford, I noticed a story on the BBC news website which was about the unemployment figures.

[E]

And the story said that the number

[B]

of people who are unemployed had gone up, but that the unemployment rate had stayed the same. And I was just a bit puzzled and wondered how that could be the case. Well, our reporter Ruth Alexander has been puzzling over this too. What's going on, Ruth?

[A]

Well, the BBC news website, the Telegraph and also the Associated Press and Reuters news agencies reported this week that unemployment has gone up by 49,000 to 2.5 million people over the three months to November. But the unemployment rate they reported remained unchanged at 7.9%.

[B]

I could understand why Sonia looked at that twice. I mean, 49,000 is quite a lot of people. You would think it would make a differ to the measured unemployment rate.

[A]

Well, you would. And the Office for National Statistics, which publishes the unemployment statistics, says, in fact, the rate has gone up by 0.2 percentage points.

[B]

So why have the BBC, the Telegraph, associated Press and Reuters all reported that it hasn't gone up?

[A]

Well, they've inadvertently mishandled the official figures. What they've done is they've compared the latest unemployment rate figure which covers the three months to November with the one published last month which covers the three months to October, seems reasonable enough, but wrong. The Office for National Statistics says that the unemployment figures are based on a survey and that the survey's findings are only reliable if you look at a whole three month period. If you compare the figure announced this month with that announced last month, you're effectively comparing two overlapping three month periods, which means you'll count the same two months twice and end up comparing two single months with each other, August and November, which don't capture enough of the people in the survey.

[B]

So the Office for National Statistics prefers to compare the unemployment rate for September to November with a previous three month period, June to August.

[A]

Exactly. So the unemployment rate for the three month period ending in August was 7.7% and the rate for the three month period ending in November was 7.9%, which shows a 0.2 percentage point rise.

[B]

All has become clear. Thank you, Ruth. You're listening to More or Less with me, Tim Harford, in association with the Open University. Our website is BBC.co.uk more or less, which is the place to go to subscribe to our podcast so you won't miss the first program in our new series and also the place to listen to archived episodes such as our Christmas Eve special in which Ebenezer Scrooge meets the spirits of banking past, banking present and banking future. Now, a number of listeners wrote to call our attention to a sudden outbreak of mathematics in the House of Lords. There was an all night debate on a bill which, among other things, proposes to reduce the number of parliamentary seats to 600. Here's Lord Harris in the wee small hours of the morning.

[C]

So what then were the reasons for choosing the figure 600 as opposed to 650 or 630, or 575 or 585? I was tempted for a moment that there was some sort of arcane numerology about this. We will be aware that 650 is the product of three prime numbers, 2, 5 squared and 13. 630, of course, is the product of four prime numbers, 2, 3 squared, 5 and 7. Now, I defy anyone to find a formulation, a number in this general order which involves five prime numbers.

[B]

Lord Harris proving beyond any reasonable doubt that the time honoured tradition of filibustering is alive and well in the Lords. It was slightly odd of him to list the prime factors of various numbers, given that all natural numbers, except perhaps one, have prime factors. But we can assure the noble lord, that nobody will pick up the gauntlet he's thrown down. Multiply together the five smallest primes, 2, 3, 5, 7 and 11, and you get 2,310. Too many MPs, I think for most people's taste. You're listening to more or less. And although it's a busy program today, we wanted to make time to hear from the Chancellor of the Exchequer, George Osborne. And of course we're paying off the nation's credit card, which is absolutely crucial to all of this. So we want to get Britain's economic house in order to, given the mistakes and the mess that we inherited, paying off the nation's credit card. Well, we ticked off the trade Union leader, Len McCluskey last week for confusing debt and the deficit, and now it turns out that even the Chancellor is susceptible to this error. Presumably, Mr. Osborne is alluding to his plans for reducing the deficit, but that's not the same thing as paying off any debt. Mr. Osborne's spending cuts and tax rises, for all that they're described as bold by his friends and swingeing by his enemies, are merely reducing the rate at which the nation's credit card bill grows. According to the Office for Budget Responsibility forecast, which accompanied June's budget, the national debt will continue to rise in nominal terms for at least the next five years. Relative to GDP, it won't start falling until 2014. So it's a little early to suggest that the nation's credit card bill is being paid off just yet. This is the last, more or less, for over two months. So for those of you wondering where to get your fix of numbers in the meantime, we thought we'd suggest some light between series reading. But what to recommend? I sat down to chat about favourite maths and science books with Rachel Riley, Countdown's number Cruncher, and Alex Bellos, the author of Alex's Adventures in Numberland.

[D]

My book is the first six books of the Elements of Euclid in Colour.

[B]

Now, of course, most loyal more or less listeners will know all about Euclid, but just help us out.

[D]

Euclid is the father of geometry and Elements is where he set down all the knowledge that the Greeks had of basic geometry. So it starts very, very simple, about points and curves and lines and right angled triangles. But the most intriguing and interesting and sort of wonderful version of Euclid's Elements was this version of Euclid's Elements in color. And the way the author Oliver Byrne did it is that rather than do the proofs with, you know, line a To B, then C to D, then if that's a right angle, it gets quite complicated. And for all the wonders in Euclid is actually quite a dense and quite a difficult book. Whereas he presented it by making it sort of color coded. And this is from 1847, so it predates any kind of color coding in explaining math in math textbooks. And actually, if you look at the

[B]

book which I've got here, it's amazing. Pass it round.

[D]

I don't actually have the 1847 version because they're incredibly rare, and I just thought Christie's just sold one for £12,000. But Taschen, the German publishing company more famous for kind of soft porn books, has come out with a facsimile of it this year. And it is beautifully, beautifully done. It comes in its own little box. But to me, you know, soft porn is geometry. I don't know about you, actually. If you look through, you know, the colours, the oranges, the reds, the blues, the blacks, the geometric lines, it really is like sort of Mondrian or sort of the beginnings of modern art, but decades before modern art began, it does add to what we understand or the ways we understand about geometry, because we begin to think about things visually in a different way.

[B]

It is beautiful, especially on the radio. Rachel, do you find that the visual element of maths is very important?

[H]

Yeah, I think people learn in completely different ways. And the good thing about maths is there's no right way of doing something, or there's lots of white rays, I should say. And this just rips apart all the standard notation and symbols and just shows it in a really clear, really bright, very decorative way. I mean, I can't see myself sitting next to a pool with a margarita reading it, but it is beautiful.

[B]

Alex, has this changed the way you think about Euclid?

[D]

Yeah, I think it has, because I went back to the first principles and went and tried to read Euclid, and it's actually a lot more difficult than you might think.

[B]

Even though I might think it's quite difficult.

[D]

Well, for a book which has only the Bible, has had more editions, you would have thought to be that popular across the ages, it might be kind of accessible. It's not actually very accessible. And here it just gives a freshness and a playfulness.

[B]

I guess for some people, this is among the purest forms of maths. I must admit. Geometry never really did anything for me. I mean, Rachel, was this the kind of thing that got you into maths or.

[H]

Not especially. I mean, I'm more interested in applied maths. And that's very pure because it just

[D]

as pure as you can get. Because essentially geometry is about measuring the world. But where in the world do you have, you know.

[H]

Perfect.

[D]

Yeah, exactly.

[B]

Speaking of applied maths, the next book we're looking at is very much applied. It's Michio Kaku's Physics of the Impossible. Rachel, you've chosen this book.

[H]

I found it fascinating and just accessible to someone that's interested in maths. And this is just really visual. I mean, it quotes things like Back to the Future, Sherlock Holmes, HG Wells. It takes science fiction elements from films, from books and explains what could be possible in terms of physics, in terms of the physics that we know or the physics that don't violate the laws that we know.

[B]

I love the way that it sort of starts off and says, well, wow, in Star Trek they got four shields, so could we have four shields? In Star wars they got lightsabers, could we do lightsabers?

[H]

It makes you think. It's just really creative physics. I mean, he separates it out really nicely. So there's class one, two and three levels of impossibilities. And the class one was the things that interested me the most. It was things that, with the technology that we have now and the knowledge that we have now, these things could be possible in the next hundred, two hundred years. So quantum teleportation. And a lot of people don't realize that quantum teleportation has been done. And it's just interesting for him to just with the power of thought, he's thinking the possibilities of what could happen if technologies progressed.

[D]

I had sort of mixed feelings with that book because in a sense it's a bit sort of a spoil sport book. It's saying you've got all these great science fiction ideas, fantasies about the future, and it's saying, can't do that. I could do that. So you have this mixture on one hand, you're thinking, oh, this is exciting. And then you're thinking, oh, no, no. Time travel, what a shame.

[H]

He uses examples of things, you know, 100 years ago that they didn't think was possible. So just over 100 years ago they declared that all science was known. Nothing's going to be found out.

[B]

Kelvin. I think heavier than air flying machines are impossible.

[H]

Exactly. And Einstein wasn't sure about black holes. So things that we think are crazy at the moment, like hoverboards, there's the high speed trains. It's just examples of crazy ideas that have actually been used in carbon nanotubes and all kinds of things that you wouldn't think were possible are actually possible. Some of them are in labs at the moment and some of them are being developed.

[B]

Yeah, I think you're being slightly unfair, Alex. I mean, it's certainly not the kind of book where it's a physicist watching Star Wars. Well, it's just a bunch of nonsense. I mean, he's saying, could this be possible? In what ways might it be possible? How soon might it be possible? And using what physical laws? Although he sometimes concludes, actually no, we can't do it. He certainly tries. He doesn't just. He's not in debunking mode.

[D]

But science fiction is all about fantasy and he's trying to be very rational and looking at that. Fantasy is fancy and what is not fancy. And sometimes it's quite sad to realize something we think might be happening isn't going to happen.

[H]

Things to do with magic or science.

[D]

I mean, I think you're always going to get the sort of wizard of Oz moment.

[H]

I mean, things that are magic are impossible because they don't exist. But he's just showing me how you can make things invisible to microwaves and possibly, you know, light in the future. And it's quite inventive.

[B]

Speaking of inventive, the book that I've chosen is nothing if not that. It's Douglas Hofstadter's Godel, Escher Bach, An Eternal Golden Braid. I mean, it's about 800 pages long. Excursion into artificial intelligence, music, literature, in particular, the relationship between formal logic and artificial intelligence. One of the things I love about it, it is very hard, it's very challenging. But the way that Hofstadter will take no prisoners will have quite a complex technical chapter on, say, formal logic or recursive loops or programming. He keeps losing me, but then he brings me back again and he's incredibly playful.

[D]

It's a very, very funny book, isn't it?

[B]

One of the dialogues in the book can be read backwards or forwards, and it reads the same way. It's those kinds of jokes in there. Alex, I know you've been investigating Godel.

[D]

One of Godel's theorems says that in any sort of mathematical system you get statements that can be true but not provable. And this sounds very kind of complicated. What type of sentences are they? And these sentences are these sort of self recursive, self referential. This thing of self reference in terms of. Is it the basis of consciousness but also self reference is very funny if you think about it. You know, Bradshaw Marks one of the most famous jokes. You know, I'd never be a member of a club that would have me as a member. We think that's funny. But that is essentially a self referential, you know, logical sort of paradox. And I think what's great is the way that he takes very difficult sort of conceptual mathematical things and makes them funny.

[B]

Well, there are a lot of ideas in the book that are, I think, possible in theory and possibly not in practice. He's writing a book in the 1970s about what computers might one day be able to do and he's, he's not greatly constrained by the limits of computers as they existed in the, in the day. He's much more constrained by the idea of what could a computer produce logically and could it ever achieve an intelligent state.

[H]

Michikaku also, I mean, I had a look at that chapter because Micho Kaku did look at artificial intelligence and I thought, I wonder if there's any overlap. And I think after, you know, one paragraph there was no overlap. I had no idea what was going on. It was quite complex. It was quite heavy reading. I think some parts of your book are playful and some of it is computer speak.

[B]

It's a lesson that there are, of course, different kinds of physics, different kinds of maths, different kinds of logic. We've explored some of them today. Rachel Riley, Alex Pelos, thank you very much.

[H]

Thank you.

[B]

Those books again. Oliver Byrne's version of Euclid's Elements, Michio Kaku's Physics of the Impossible, and Douglas Hofstadter's Godel, Escher Bach. We received a flood of emails when last week I explained that our national debt might be a thousand times smaller than. Well, let's stop right there. Listener Martin Foreman complained that the word times implies something bigger. When the mind hears the phrase X is a thousand times, it automatically expects the comparison to be larger. If the next word is smaller, there's an inherent contradiction and the mind has to go into reverse. There were many other emails. I understand the grumbles, but my choice of words was not an accident. Take the phrase five times poorer. It can't be translated literally into a formal mathematical expression, but it's obviously the opposite of five times richer. If Yemen is five times richer than Liberia, then Liberia is five times poorer than Yemen. That doesn't seem especially counterintuitive. Now I could of course say instead that Liberia is one fifth as rich as Yemen, but that's a mouthful. And if I'm focusing on Liberia, it's odd to say Yemen is five times richer than Liberia. The emphasis is wrong. And anyway, Liberia isn't rich and neither is Yemen, so why talk about how much richer one is than the other? So my challenge to all loyal tell me how much poorer Liberia is than Yemen while preserving my emphasis and my word count. If you can solve my conundrum, I'd love to hear about it. Now, a few listeners have got in touch to ask whether there's a case for renaming the program More or Fewer. Good question. The answer? No, there isn't. But we do believe that less is more. So we'll wind up our series here. We'll be back on April 1, auspiciously enough. So all that remains is to step out here onto the roof of White City, where the More or Less flag flies proudly during each series. Wes, could you give me a hand, please?

[E]

Yes. I hadn't realised it would be this high up.

[B]

Well, be careful, it's frosty.

[E]

Yes, I'm windy. Perhaps this isn't such a good idea after all.

[B]

Don't worry. I've been clambering over this roof since I was a boy.

[E]

Really?

[B]

Yes. Just need to get him in.

[E]

Interesting. 2 seconds. 20 meters. It looks like you're right all along.

[D]

Tim?

[H]

Tim.

[A]

More or Less was presented by Tim Harford, the FT's undercover economist.

[H]

The producer was Richard Knight and the

[A]

editor was Richard Varden. It was made in association with the Open University.