More or Less

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1152

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Oct 2026

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Tim Harford explains - and sometimes debunks - the numbers and statistics used in political debate, the news and everyday life.

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October 31, 20268 min

Europe's witch trials: The numbers behind the myth

Witches and witchcraft have captivated people for centuries. From the curse tablets of Ancient Greece to the witch of Wookey Hole, belief in magic has long been woven into human culture. But accusations of witchcraft have also had deadly consequences. Across Europe, tens of thousands of people were investigated, prosecuted and executed during the witch trials that swept the continent peaking during the late 16th and early 17th centuries. One statistic is repeated again and again: that nine million people were killed during the witch trials. But where does that figure come from, and does the historical evidence support it? In this episode, we speak to historian Dr Jan Machielsen about the reality behind this claim, exploring what the numbers can tell us about this dark chapter in European history. If you have a story you'd like us to investigate, please contact moreorless@bbc.co.uk . Presenter/Producer: Lizzy McNeill Series Producer: Tom Colls Editor: Richard Vadon Production Co-ordinator: Maria Ogundele Sound Mix: James Beard

October 24, 202610 min

Terence Tao: Maths ‘the canary in the coal mine’ on AI

Terence Tao is widely celebrated as the world’s greatest living mathematician. He was doing university-level maths at the age of 9, won Gold at the International Mathematical Olympiad at 13 - still the youngest person to have done that - and got his PHD at age 20. At 31 he won the Fields Medal - somewhat equivalent to a Nobel Prize for pure mathematics. He has now embarked on what some might consider the greatest challenge of his life - he’s written a book for a general audience, called Six Maths Essentials. This provided the opportunity for Tim to interview Professor Tao. They talked about maths, and the relevance of his kind of abstract maths on everyday life. And they also talked about AI. OpenAI recently released full or partial solutions to 372 unsolved mathematical problems, which has raised existential questions about Tao’s profession. Professor Tao says the disruption in his field might make it “the canary in the coal mine” for the disruption AI is going to create across our way of life. Credits: Presenter: Tim Harford Series Producer: Tom Colls Production Co-ordinator: Maria Ogundele Sound Mix: James Beard Editor: Richard Vadon

October 17, 20268 min

Did Ukrainian strikes on Russian data centres stop disinformation bots?

Last week, Ukraine launched drone attacks against three data centres owned by Russian tech giant Yandex. After these attacks Yandex announced that they were struggling to maintain their services. This led to widespread claims that Russian disinformation campaign on social media had been affected, as users produced graphs that they argued showed a dramatic decline in suspicious online activity by bots. The claim was even made by the Ukrainian President, Volodymyr Zelenksy, saying there was “less hate” online as a result of the strikes. But as the dust settled, it became clear that this wasn’t the simple success story many people hoped it would be. We speak to Shayan Sardarizadeh from BBC Verify and Amil Khan, the co-founder and CEO of Valent. If you’ve seen a number, or a graph, that you think we should look at, email the team: moreorless@bbc.co.uk Credits: Presenter: Lizzy McNeill Producer: Nathan Gower Series Producer: Tom Colls Production Co-ordinator: Maria Ogundele Sound Mix: James Beard Editor: Richard Vadon

October 14, 202629 min

Fact-check: Will Scottish pensioners really be funding English social care?

Tim Harford investigates some of the numbers in the news. This week: (00:40) First Minister John Swinney has claimed that Scottish pensioners are set to lose £2000, with the money going to fund English social care. We gently suggest he might like to consider the existence of the Barnett formula, and explain that, when you do, the picture looks very different. (06:08 ) The Liberal Democrats have dug out data on maternity injuries that they claim is ‘a shocking indictment of our NHS maternity services’. We explore flaws in their analysis and ask an expert what a better source of data tells us about maternal healthcare. (13:20) Professor Terence Tao is good at maths. Extremely good at maths. We ask him how he feels about AI being better at maths than him. (15:49) Great news! The UK is reducing its deficit at the fastest rate of any G7 nation. Except we’re not. Ah, shame. But we are planning to! Fantastic! But we’ve got reason to be sceptical of these plans. That’s a pity. Join the FT’s Chris Giles on the economic and emotional rollercoaster that is the UK’s fiscal trajectory. (21:14) The series reaches its intellectual zenith as we ask what would happen if you ‘put the whole of the country into baked beans’. Expect back of the tin workings, cutting edge agri-science research and true public service journalism. Just don’t ask what the nadir was. Guests: Dr Spencer Thompson - Senior Knowledge Exchange Fellow at the Fraser of Allander Institute Professor Marian Knight - Director of the National Perinatal Epidemiology Unit at the University of Oxford Chris Giles - Economics Commentator at the Financial Times Professor Terence Tao - Professor of Mathematics at UCLA Presenter: Tim Harford Series Producer: Tom Colls Reporters: Nathan Gower and Lizzy McNeill Editor: Richard Vadon Programme Coordinator: Maria Ogundele Sound Engineer: James Beard

October 10, 20268 min

Fact-check: Is China missing a billion people?

A viral video circulating online claims the population of China is actually a billion people lower than the UN and China say. A billion is big number, you'd think the Chinese would notice if that many were missing - and the claim is certainly false. However, as the team dug into the stats, a strange story emerged - which suggests the official data on births and fertility may not be quite as reliable as you might think. We spoke to demographer Professor Sabu Padmadas from the University of Southampton to find out more. If you spot a story you'd like us to dig into contact us at moreorless@bbc.co.uk Presenter: Tim Harford Reporter: Lizzy McNeill Series Producer: Tom Colls Editor: Richard Vadon Sound Mix: James Beard

October 7, 202628 min

Is the UK state pension really the lowest in Europe?

Tim Harford investigates some of the numbers in the news. This week: (00:42) Is the UK uniquely miserly when it comes to the state pension? That’s the story a viral social media post is telling - but have they adjusted to account for complicated structural differences between national systems? Reader, they have not. (07:23) In a podcast feud nobody saw coming, Sir Jacob Rees-Mogg and Tucker Carlson recently locked horns over whether Russia or UK has a larger economy. Who's right? Only one person can possibly adjudicate this one: Duncan Weldon. (15:06) What effect did this year’s heatwaves have on excess deaths? We analyse the mortality data and explore how, despite thousands of deaths associated with the heat, 2026 is so far setting a record low mortality rate. (22:35) And finally, in an ‘and finally’ story to end all ‘and finally’ stories, we finally ask how many times the world population can fit into Loch Ness. And Lake Baikal. And, finally, the Caspian Sea. Guests: Heidi Karjalainen – Senior Research Economist at the Institute for Fiscal Studies Stuart McDonald – Partner and Head of Longevity and Demographic Insights at consultancy firm Lane Clark & Peacock Duncan Weldon – Economist and author of ‘Blood and Treasure: The Economics of Conflict from the Vikings to Ukraine’ Dr Keith Still – Director of Crowd Risk Analysis Presenter: Tim Harford Series Producer: Tom Colls Producers: Nathan Gower, Lizzy McNeill, Kateryna Pavlyuk Editor: Richard Vadon Programme Coordinator: Maria Ogundele Sound Engineer: James Beard ARCHIVE: The Tucker Carlson Show, YouTube

October 3, 20268 min

The Uzbekistan-shaped hole in an influential climate cost paper

How much could climate change cost the global economy? That would be a very useful thing to know, and scientists have developed statistical models that they think can help give a reasonable answer. These involve finding the patterns in economic data associated with temperature changes - and then applying them to the future changes that are predicted as the globe warms. In 2024, a scientific paper was published that apparently offered the most accurate projection yet of that potential cost - analysing the impact of temperature on economic activity at a far more granular level than had been attempted before. The paper quickly became highly influential. And then at the end of 2025, it was retracted. Why? It’s all got something to do with Uzbekistan. Solomon Hsiang, Professor of Global Environmental Policy at the Stanford Doerr School of Sustainability, explains how he and his team identified the problem. Presenter: Tim Harford Series Producer: Tom Colls Production Co-ordinator: Maria Ogundele Sound Mix: Dave O’Neill Editor: Richard Vadon

September 30, 202630 min

Does the UK really have nine out of the ten poorest regions in Northern Europe?

Tim Harford investigates some of the numbers in the news. This week: (00:40) Does the UK account for nine out of ten of the poorest regions in Northern Europe? It’s a classic story of devil meets detail where the true meaning is the geographical inequality we met along the way. (07:54) An article in The Economist has claimed that a single donkey charity in Devon received more in annual donations than all the major political parties combined. Is this true? And if so, should we be Led by Donkeys? (11:29) Last week 781 migrants crossed the channel in small boats in one day. Social media is keen to work out how much this might cost the UK economy. We put the numbers in context and ask Madeleine Sumption from the Migration Observatory about the fiscal impact of asylum seekers. (21:38) A claim has been buzzing round the internet that bees could hold the secret to long life, but our team is sceptical. We deliver the statistical exposé of Big Honey that the mainstream media’s been too afraid to cover. Guests: Liam Sides, Associate Director at Oxford Economics’ Cities and Regions team Dr Madeleine Sumption, Director of the Migration Observatory at the University of Oxford Professor Dot Bennett, Professor of Cell Biology at City St. George's, University of London Dr Ramsay Bowden, Consultant in Clinical Genetics at Cambridge University Hospitals Presenter: Tim Harford Series Producer: Tom Colls Reporters: Lizzy McNeill and Kateryna Pavlyuk Producer: Nathan Gower Editor: Richard Vadon Programme Coordinator: Maria Ogundele Sound Engineer: James Beard

September 26, 20269 min

Trump fact-check: Do the US and Venezuela have 60% of the world’s oil?

US president Donald Trump has claimed in a speech to the UN that the US and Venezuela combined now have 60% of the world’s oil. 100% of the team on More or Less were confused. What measurement was the president using to get to this figure? Barrels of oil produced a day? Reserves of oil in the ground? It’s hard to make any of these stats add up. To find out whether there was any truth in the claim, we spoke to energy expert Bill Farren-Price of the Oxford Institute for Energy Studies. If you spot any numbers you think we should take a look at, email us at moreorless@bbc.co.uk Presenter: Tim Harford Producer: Lizzy McNeill Researcher: Kateryna Pavlyuk Series Producer: Tom Colls Editor: Richard Vadon Sound Mix: Neil Churchill

September 23, 202629 min

Has the UK’s productivity puzzle been solved?

Tim Harford investigates some of the numbers in the news. This week: (00:42) Frustrated economists have been left rending their garments and howling in the streets after the UK’s ‘productivity puzzle’ - a decade-long head-scratching, soul-searching conundrum - disappeared with a click of the fingers and a tweak of the methodology. Should the Office for National Statistics have acted sooner? We ask Financial Times economic guru Chris Giles. (07:26) Can it really be true that by the 1960s, one in ten Irish children entered religious orders? Reporter Lizzy McNeill has the answer, and the history. (13:51) Is the AI datacentre goldrush threatening to swamp our electricity grid? And what are the consequences for its carbon footprint? We delicately untangle the live wires of this hot potato and give the people what they want: nuanced #GridChat. (20:38) This is the way the album ends - not with a banger, but with a whimper. Music Substacker Mitchell Stirling has used data to test the decades theory that albums tend to end with a quiet track. Come for the explanation of the physics of vinyl, stay for whatever music we end up being able to use. Guests: Chris Giles - Economics Commentator at the Financial Times Johnny Gowdy - Director at Regen Mitchell Stirling - Substacker, data nerd, music nerd (Renaissance man) Presenter: Tim Harford Series Producer: Tom Colls Reporters: Nathan Gower and Lizzy McNeill Editor: Richard Vadon Programme Coordinator: Maria Ogundele Sound Engineer: James Beard