In 1942, eight men are sent from Nazi Germany to infiltrate America. Their mission: to sabotage critical infrastructure. Their problem: they’re idiots. Operation Pastorius soon devolves into one of the most baffling failures of World War II.

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Further Reading

The tale of Operation Pastorius is told in They Came To Kill: The Story of Eight Nazi Saboteurs in America, by Eugene Rachlis, and Saboteurs: The Nazi Raid on America, by Michael Dobbs. The classic experiment of the smoke-filled room is Bibb Latane and John M Darley’s Group inhibition of bystander intervention in emergencies. And if you think you might have seen Joseph Schmidt, please contact J. Edgar Hoover.

This is a special crossover episode with Business History.

John DeLorean was a visionary who wanted to create a futuristic new sports car – a stainless steel marvel with distinctive gull-wing doors. The British Government agreed to finance the project, provided DeLorean built his factory in a troubled part of Northern Ireland. Production stumbled, sales fizzled and DeLorean liked to fiddle with the numbers. As the company approached ruin, a neighbour offered DeLorean a lifeline, if he’d only come in on a cocaine deal.  

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It was a viral hit, as was the follow-up book, Thing Explainer (2015), and it produced an intriguing reaction from the science-communication community, who are among the most enthusiastic of Munroe’s many fans. First, there was a burst of people trying to explain their own fields using the same constraint. Then came the backlash.

“Condescending”, wrote one science blogger. “By talking down to our audience, we risk alienating them, and reinforcing the common preconception that scientists consider and hold themselves apart from non-scientists.” The great science writer Carl Zimmer criticised the craze (not the cartoon) for encouraging the idea that there was anything useful in the constraint. The craze was, he argued, a disheartening waste of time for any scientist trying to figure out how to explain their field to a lay audience, because they might wrongly conclude that it was hopeless to try.

Well, maybe. Up Goer Five is tremendous fun but more puzzling than pellucid. The typical three-year-old can recognise 1,000 words, and there is nothing particularly clarifying about trying to explain something complicated while limiting oneself to the vocabulary of a three-year-old.

Nevertheless, unreasonable-seeming constraints can produce surprisingly powerful results. The artist and writer Theodor Geisel was once given the challenge of writing a book for six-year-olds while deploying no more than 225 different words from a short list. At first, Geisel was frustrated at the lack of adjectives; it was “like trying to make a strudel without any strudels”. But then, as David Epstein explains in his book Inside the Box: How Constraints Make Us Better (2026), he grabbed the first two rhyming words and went for it. The result, The Cat in the Hat (1957), made Geisel — better known as Dr Seuss — a phenomenon. Green Eggs and Ham (1960) is even better, and while it is packed with crazy situations, it contains only 50 unique words, making Up Goer Five seem positively lexiphanic. (Dr Seuss took on that challenge to win a bet.)

In the arts, the value of constraints is not a new idea. Monet almost never used black paint. Bach tied himself in knots with self-imposed rules, and part of the joy of his music comes from hearing him untie and retie them with ease. Miles Davis recorded Kind of Blue (1959) with no rehearsal, minimal composition and used the first take of each piece.

But when it comes to a more practical problem, is it really tenable to impose needless constraints? Perhaps it is. The simplest constraint for anyone trying to explain a complex topic is to accept the request to “explain it to me like I’m 10 years old”. What’s packed into that request is, vividly exaggerated, the reminder that what seems obvious to an expert is often incomprehensible to the listener. Technical jargon and fusillades of acronyms are often used to convey an explanation that has been denuded of all the foundations and context that might allow it to make sense.

Worse, in a kind of inverted Dunning-Kruger effect, the very expertise that makes the expert worth consulting also makes it hard for the expert to imagine what it was like to know nothing about the topic.

Hence “explain it to me like I’m 10 years old”. If you are reading this column you definitely aren’t a typical 10-year-old, but the image of the bewildered 10-year-old gives the expert an anchor to help them slow down and simplify. My book, The Truth Detective, was supposed to be a version of How to Make the World Add Up for 10-year-olds. My wife tells me she prefers it to the one that was for the grown-ups.

What is true in technical communication may also be true in design. David Epstein describes the moment the US Army tried to adapt its body armour for female soldiers. As Caroline Criado Perez forcefully argues in Invisible Women, women are not merely scaled-down men and are not well served by equipment designed for men. But as the US Army started grappling with that challenge, they discovered some surprising benefits. They were able to replace 11 sizes of body armour with just eight sizes by making the armour a modular mix-and-match system. This simplified manufacture and logistics while greatly expanding the options available to an individual soldier.

Meanwhile, many of the men in the army found the “female” modules a better fit — a narrow vest gave room to soldier a rifle, while a notch in the back of the helmet designed to accommodate hair buns allowed all soldiers, regardless of hair-do, to raise their heads while prone. “A new, more meticulous sizing process that benefitted women benefitted everyone,” Epstein writes.

A similar story can be told about designing for people without a full range of mobility or senses. In 1972, design professor Marc Harrison and his students produced a demonstration house full of features that accommodated users with special needs — flat thresholds between rooms made life easy for wheelchair users and people on walking frames; levers on taps and door handles are easier to use for people with a weak grip. But, of course, levers are easier for anyone to use — try twisting an old-fashioned doorknob with a cup of coffee in each hand.

Subtitles help people who can’t hear what the actors are saying — and it turns out that, for some gritty dramas, that is all of us. Web pages that are designed with screen readers for the blind in mind are typically better structured, simpler and friendlier for mobile devices. The Oxo kitchen appliance company was founded by a retired cookware entrepreneur whose wife had arthritis, but the chunky rubber handles are far more widely enjoyed. And of course, the dropped kerb may be life-changing for wheelchair users but it is pretty convenient for anyone pushing a pram.

The challenges faced by users who are unusually small, large, old or young, or who have disabilities, are, writes Epstein, “more extreme versions of the challenges that many other users face”.

Of course, we should not make the mistake of arguing that the reason we should design for disabled people is to help the majority, or that we should design for women because of the benefits for men.

But in a world where it is often hard to put ourselves in the shoes of someone else, the challenge of explaining the world to a 10-year-old, or designing a jar that an octogenarian can open, is sometimes just a prompt to do a better job of what we were trying to do in the first place.

Written for and first published in the Financial Times on 15 July 2026.

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The key source for this episode of Cautionary Tales is The Improbable Victoria Woodhull: Suffrage, Free Love, and the First Woman to Run for President (2025) by Eden Collinsworth.

It also draws on the following articles, books and websites:

“The Beecher-Tilton Scandal Case“, Woodhull and Claflin’s Weekly, vol. 5, no. 7 (2nd November 1872)

“Notorious Victoria: the first woman to run for president” by Eileen Horne, The Guardian, (20th July 2016)
“Moral Pests“, The Dundee Courier (23rd November 1872) “Printing Newspapers 1400-1900: A Brief Survey of the Evolution of the of the Newspaper Printing Press” by Joanna Colclough, Headlines and Heroes: Newspapers, Comics and More Fine Print (21st April 2022)

“Designing Organisations for an Information-Rich World” by Herbert Simon, in Computers, Communications, and the Public Interest (1971)

The Attention Merchants by Tim Wu (2016)

www.measuringworth.com

Talented and beautiful, Molly O’Day is a rising star in 1920s Hollywood. But when Molly’s teenage body starts to change and she can no longer fit into the dress she wore when she was 16, the studio wants nothing to do with her. As the scripts dry up and the money runs out, Molly faces a difficult but painfully familiar choice.

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Books

Hollywood and the Rise of Physical Culture (2003) by Heather Addison.

Silent Stars Speak: Interviews with Twelve Cinema Pioneers (2000) by Tony Villecco.

Articles

“Los Angeles, a Miracle City: L.A. in the 1920s” by Danielle Ball, Los Angeles PublicLibrary (28th January 2026).

“Looking Like a Flapper Meant a Diet of Celery and Cigarettes” by Anne Ewbank, Atlas Obscura (20th April 2018).

“The Screen” by Mordaunt Hall, The New York Times (16th August 1927).

 “Cosmetic Surgery on Trial: How the Dujarier Case Impacted its Practice and Structure in France during the Interwar Period” by Yannick Le Hénaff , in Social History of Medicine, Vol. 0, No. 0 (2017), pp. 1-22.

“Molly O’Day; Actress in ‘Our Gang,’ Films” by Myrna Oliver, Los Angeles Times (21st October 1998).

“Starving Back To Stardom: The sad story of Molly O’Day whose career was blighted by ice cream and candy”” by Lois Shirley, Photoplay (August 1928).

“Obituary: Molly O’Day” by Tom Vallance, The Independent (28th October 1998).

“History’s weirdest fad diets” by Denise Winterman, BBC News Magazine (2nd January 2013).

“Easy Come, Easy Go in Movies; Sisters Now Are Bankrupt”, Alburquerque Journal (10th November 1930).

 “Molly has own ‘slogan’ as she plans comeback”, Mansfield News Journal (21st January 1937).

“The Patent Leather Kid”, New York Times (14th August 1927).
 “Surgeon Carved Off Mollie O’Day’s Fat — But It Came Back”, San Antonio Light, (20th January 1929).

 “Molly O’Day, the Girl in ‘The Patent Leather Kid’ to Play Thru Wednesday at the Kettler Theatre”, The Palm Beach Post (4th March 1928).

“Actresses Rushes to Relief of Mothers in New Association”, The News (13th January 1928).

“Wanted — An Irish Moniker”, The Record (18th April 1927).

“3 mos. for 25 lbs.”, Variety (October 1927).

“Sliced Hips And Legs Save Miss Molly O’Day”, Variety (5th September 1928).

“86th Street”, Variety (4th June 1930).

“Molly O’Day”, Variety (7th December 1998).

“Weight-Reducing Molly O’Day Is Losing Out”, Variety (December 1928).

Podcasts

“152: Hollywood’s First Weight Loss Surgery: Molly O’Day” by Megan Koester, You Must Remember This (21st January 2020).

Websites and Blogs
https://thebibliofile.substack.com/p/lux-soap-and-the-americanization

 https://immortalephemera.com/wampas-baby-stars/

For the story of Mary Linnen, the key source was Dispensing with the Truth: The Victims, the Drug Companies, and the Dramatic Story Behind the Battle Over Fen-Phen (2010) by Alicia Mundy. We also drew on several articles.

Articles

“The New Miracle Drug?” by Michael Lemonick, Time Magazine (23rd September 1996).

“How Fen-Phen, A Diet ‘Miracle’, Rose and Fell” by Gina Kolata, The New York Times (23rd September 1996).

“A Little Vanity, a Lot of Corporate Greed: a Killer Combo” by Judy Mann, The Washington Post (6th June 2001).

“Fen-Phen Case Lawyers Say They’ll Reject Wyeth Offer” by Stephanie Saul, The New York Times (17th February 2005).

“AHP Settles Suit Alleging Fen-Phen Death“, Los Angeles Times, (28th January 2000).

 “Diet drugs re-examined after woman’s death”, The Minnesota Daily (7th May 1997).

 “Fen/phen death suit settled”, United Press International (28th January 2000).

It must have been a spectacular sight, with the tallest mast standing almost 50 metres above the water, and the ornately carved stern of the ship towering above the waves as though some baroque cathedral organ had floated out into the Baltic.

None of this lasted for more than a few minutes. Vasa had drifted for about a mile when a gust of wind caught the ship from the side, pushing it into a pronounced lean — pronounced enough, in fact, that some of the gunports dipped below the waterline. The ship shuddered and then swiftly and inexorably sank to the bottom of the harbour, sailors desperately clinging to the masts as they protruded from the surface.

In any other circumstance, nearly 450 men would have drowned. Fortunately, the ship’s crew had not yet embarked, most of the sailors were on the upper decks, and there were plenty of boats nearby to stage a rescue. Nevertheless, about 40 people are thought to have died. The captain, Söfring Hansson, survived and was immediately arrested.

The waters of Stockholm’s harbour — cold, oxygen-starved and brackish — proved to be a safe resting place for the wreck, which was recovered 333 years after sinking. Today, Vasa is the breathtaking centrepiece of one of Stockholm’s most popular museums. Adolphus was out on campaign, and nobody in Stockholm was terribly keen to break the news to him, but eventually the entire privy council got together to send a collective report. Adolphus’s furious reply demanded to know who was responsible.

Even four centuries later, the sinking of Vasa is an instructive affair, although it is important to draw the right lessons. A 2001 paper in The Academy of Management Executive is titled “Vasa Syndrome: Insights from a 17th-Century New-Product Disaster”, and offers various gems — for example, that the shipwrights should have clarified the customer’s goals, which would have revealed a crucial but unstated preference for a ship that floats.

The first lesson I draw is to plan for failure, because in bold new projects it is common. That’s not just business-school pablum — the engineer Henry Petroski, in his book Success Through Failure, describes the tendency of bridge engineers “overconfidently building increasingly longer bridges modelled on successful prior designs”. There is a ratcheting tendency to try ever grander, more challenging structures, in bridges, boats and elsewhere. Correctives come in the form of rare but spectacular failures.

In the case of Vasa, the king demanded an unprecedented number of heavy guns, and the shipwright, Dutch-born Henrik Hybertsson, realised this would require a second gun deck. Hybertsson had never tried to build such a ship and in an excess of caution he over-reinforced the upper decks. The combination of massive guns supported by massive timbers on a high deck made the entire ship top-heavy. Hybertsson died early in the construction process and his deputy, Hein Jakobsson, stuck to the story that he had simply built the design approved by the king. Jakobsson had widened the ship by 17 inches, which presumably made it more stable, but claimed he had been constrained by what had already been agreed and built.

The inevitable inquiry examined a number of possibilities: was the captain drunk? Were the crew drunk? Were the cannons untied and rolling around? The final verdict was probably correct: the ship’s design was unstable from the start and Vasa was always likely to capsize. The late Henrik Hybertsson was to blame. Hybertsson could neither defend himself nor be punished. That state of affairs seemed to suit everyone.

A second lesson is not well known. The “Vasa Syndrome” paper doesn’t mention it, and the otherwise excellent guide at the Vasa museum hadn’t heard of it. But the museum’s head of research, Fred Hocker, notes that the wreck contained four carpenter’s rules, all slightly different lengths. With Dutch shipwrights carrying out a contract in Stockholm, perhaps it is not surprising to find that both the Amsterdam foot (11 Dutch inches) and the Swedish foot (12 Swedish inches) are represented. These feet are, respectively, 283 and 297mm. Probably as a result of this failure to standardise, Vasa was more asymmetric than most ships of the day, giving it a tendency to lean to port — as it did on the day it sank. This can’t have helped. And while it would be hard to imagine a project today failing because nobody could agree how many inches were in a foot, there is no shortage of cases in which apparently trivial technical details were taken for granted.

The third lesson — and to my mind the most tragic — is that disaster could easily have been prevented. The people who decided to set sail knew that Vasa was unstable. A few days before departure, Captain Söfring Hansson arranged a demonstration for his boss, Vice-Admiral Fleming: 30 sailors ran back and forth on the top deck to get the ship rolling. This was a traditional test and the sailors would typically shuttle across more than a dozen times, but the ship rolled so alarmingly that Fleming called off the test after three, muttering that he wished the king were at home.

Had Gustavus Adolphus been in town, the demonstration could have been repeated for his benefit. The ship could have been modified; even with a single deck it would have been formidable, or the upper deck could have been equipped with fewer or lighter cannon. But the king was — as usual — away on campaign, sending letters demanding that Vasa set sail as soon as possible.

Vasa did not sink because the management team failed to clarify that the customer preferred it to float. It sank because basic technical details — such as everyone using the same ruler — were overlooked. It sank because it was a dangerously innovative design, made worse by a shipwright’s attempt to play safe. And above all it sank because Vice-Admiral Fleming decided that, rather than tell the king of his last-minute concerns, he would rather go ahead and hope for the best. From Washington DC to Downing Street, Wall Street to Silicon Valley, it is a lesson that remains uncomfortably relevant.

Written for and first published in the Financial Times on 8 July 2026.

Loyal readers might enjoy the book that started it all, The Undercover Economist.

I’ve set up a storefront on Bookshop in the United States and the United Kingdom. Links to Bookshop and Amazon may generate referral fees.

Mary Bateman lived in York in the late 18th Century, an age that prized rational thought. Many people still longed to believe in the old ways and Bateman used this to her advantage, selling spells and enchantments to the desperate. Maddy Pelling, co-host of the After Dark podcast and author of Hoax: Truth and Lies in the Age of Enlightenment, joins Tim to tell the tale of the villainous Yorkshire Witch, and just how far she was willing to go.

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The Herald of Free Enterprise is a new class of ferry that allows cars to drive directly into the ship. The doors protecting the ship must be closed before every departure, or the ship sails with a gaping hole at one end. One black night in 1987, on the freezing waters off Zebrugge, Belgium, a single crew member falls asleep at the worst possible time.

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Further Reading

Iain Yardley’s book, Ninety Seconds at Zeebrugge: The Herald of Free Enterprise Story, brings together accounts form survivors. This script also relied on reporting from outlets such as The Times, the BBC, The Independent, Evening Chronicle, UPI, and Kent Online.

Mr Justice Sheen’s report is available online as MV Herald of Free Enterprise Report of Court No. 8074 Formal Investigation. The Herald’s link to James Reason’s thinking is outlined in Good and bad reasons: The Swiss cheese model and its critics by Justin Larouzee and Jean-Christophe Le Coze.

Peter Spooner reflects on the Herald disaster in “Corporate responsibility in an age of deregulation”, Chapter 8 of Hazard Management and Emergency Planning, published by Routledge in 1992. For more on the corporate law reform, see an overview from The Law Commission in 1996, Corporate manslaughter and the company director by Simon Daniels, and The Corporate Manslaughter and Corporate Homicide Act 2007 – A 10-Year Review by Victoria Roper. 

In February 1912, on a cold Sunday morning, Reichelt persuaded journalists, a camera crew and a small crowd to watch him demonstrate his new wearable parachute. The official story was that Reichelt would throw a dummy from the first floor of the Eiffel Tower, more than 50 metres up. Reichelt, however, had tipped off journalists that he would make the jump himself. Otherwise, one suspects, there would have been fewer spectators.

The parachute is, as it happens, something of a running joke in evidence-based policymaking. In the Christmas 2003 edition of the British Medical Journal, obstetrician Gordon CS Smith and public health researcher Jill Pell published a systematic review of “Parachute use to prevent death and major trauma related to gravitational challenge”. They noted, with mock sorrow, that “we were unable to identify any randomised controlled trials of parachute intervention” and called for “the most radical protagonists of evidence-based medicine” to organise and participate in a rigorous randomised trial of the parachute.

In case the joke has passed you by, the argument being lampooned is a complaint by advocates of evidence-based policymaking. Many well-established medical practices — along with ideas in policing, criminal justice, education, economics and beyond — have never been seriously tested by the gold standard for evidence: a double-blind, randomised controlled trial (RCT). RCT advocates suggest that this is a scandal. Is it?

Leave that question hanging for a moment, because 15 years later — again in the BMJ Christmas issue — a team of researchers detonated an evidential bombshell. They had run the long-missing randomised trial of the parachute — and found that parachutes were no better at preventing major injury or death than an empty backpack. Anyone surprised at this result need only consult the small print: nobody in the trial had suffered any noteworthy injury at all after jumping from an aircraft, and this is because they did so “at significantly lower altitude . . . and lower velocity”. To be more specific, they jumped out of “small stationary aircraft on the ground”. Another hilarious satire from the BMJ.

There are serious lessons here, for those who can stop sniggering. The first is that, yes, there is no need for a RCT of a technology — such as the parachute — whose benefits are indisputable. The second is that RCTs themselves do not necessarily prove anything: the researchers suggest “cautious extrapolation to high-altitude jumps”.

It is striking how incautious extrapolation can be, particularly in press releases and breathless media summaries. A small study of nursery school children drawing pictures is generalised to be a fully fledged theory of human motivation. Big claims about the benefits or risks of a food additive teeter on the questionable foundation of research on laboratory mice.

Randomisation is neither the only route to knowledge nor a guarantee of eternal truth. But it is a very good idea — which may help to explain why there have been serious randomised trials, even of parachutes. As Andrew Leigh explains in Randomistas (2018), “experiments on parachute efficacy and safety are widespread”. Some of them use crash dummies, while others investigate details of technique or equipment: paratroopers are six times more likely to suffer an ankle sprain if they jump without an ankle brace. So there.

One important reason to use some form of randomisation is that it strips away all kinds of potential confounding. Do small class sizes help students to thrive? You won’t find that out by simply comparing an overcrowded, cash-strapped inner-city academy with a lavishly funded public school: their class sizes may differ, but so does everything else. If you want to learn about learning, run a randomised experiment.

The second reason, still under-appreciated, is that experts know less than they like to think. Doctors embraced bloodletting for 2,000 years before belatedly acknowledging that it is rarely an appropriate treatment. (The Lancet is named after a bloodletting tool.) More recently, as Helen Pearson notes in Beyond Belief (2026), “In 1980s Britain . . . it was standard practice to shave pregnant women’s pubic hair when they were admitted to hospital and to give them enemas.” Episiotomies, too — cuts in the opening of the vagina — were “pretty routine”. None of this was evidence-based. It just seemed to doctors that it would be a jolly good idea.

In the summer of 2020, when the Recovery trial revealed that a cheap steroid, dexamethasone, was hugely beneficial to Covid-19 patients undergoing mechanical ventilation, one doctor told me that this so-called discovery was simple common sense. But Sir Martin Landray, one of the leaders of the trial, recalls the letters that experts had sent to him and to the regulators warning that dexamethasone — which suppresses the immune system — was so dangerous to Covid patients that it was unethical even to test it. When some experts think it’s a parachute, and others think it’s bloodletting, it’s a good idea to run the trial.

What happens when you need a decision urgently, and gold-standard evidence does not exist? One approach is to do what Landray and his colleagues did: move fast. By introducing a simple clinical trial alongside routine care, they were able to get the trial running within 10 days and produce life-saving results within 100.

But what if there is no trial, and no prospect of one? Then, argues Pearson, we need “aluminium standard” evidence. Be as clear as possible about your hypothesis, break it down into a chain of causal links, and get the best data you can — for and against — to test each link in the chain. Gold is better, but aluminium is cheap and lightweight and sometimes sufficient for the job.

Franz Reichelt was a better publicist than parachute designer. His leap from the Eiffel Tower was captured for the ages on Pathé-Journal newsreel. I would advise against watching it. He died of a shattered skull and spine, and — perhaps — of a coronary arrest mid-fall. Wikipedia simply lists his cause of death as “parachute failure”. The self-belief of a pioneer is a powerful thing. Normally, when the experts propose untested solutions, they are not the ones who suffer the consequences.

Written for and first published in the Financial Times on 24 June 2026.

Loyal readers might enjoy the book that started it all, The Undercover Economist.

I’ve set up a storefront on Bookshop in the United States and the United Kingdom. Links to Bookshop and Amazon may generate referral fees.

Windscale is supposed to be Britain’s big leap into the nuclear Age, bringing science fiction to life in 1950s Northern England. But in the race to catch up with America’s nuclear program, scientists are tinkering with forces they don’t fully understand. When the reactor catches fire, no-one knows how bad it could be, or how to put it out. As the reactor workers scramble to save lives, other eyes on Windscale are much more concerned with containing the political fallout and burying the truth.

This episode was first released to members of the Cautionary Club. For bonus episodes, ad-free listening, our monthly newsletter and behind-the-scenes conversations with members of the Cautionary Tales production team, consider joining the Cautionary Club.

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Further Reading

This script relied on two books by Lorna Arnold – Windscale 1957: Anatomy of a Nuclear Accident, and her autobiography, My Short Century. The BBC’s 2007 documentary, Windscale – Britain’s Biggest Nuclear Disaster, can be found on YouTube. In the same year, Richard Wakeford published The Windscale reactor accident—50 years on in the Journal of Radiological Protection. Bill Penney is remembered in obituaries by The Royal Society and New Scientist.