Éclat for the smartest girl in the room
Today: the mathematician who told the army to armour the planes that had no bullet holes, why double denim has a royal-rejection backstory, sunlight that spent tens of thousands of years escaping the Sun, cows painted like zebras and the chemistry of old-book smell — plus a French phrase for having too many choices and a case where everybody lies (almost).
The Big Idea · Statistics & Psychology
The Planes That Didn’t Come Back: How Survivorship Bias Fools Smart People
During World War II, a group of mathematicians at Columbia University, the Statistical Research Group, was asked how to protect bombers better. The military had looked at the planes that returned from missions and noticed that the bullet holes clustered on certain parts, like the wings and the body. The obvious idea was to add armour exactly where the holes were. The mathematician Abraham Wald saw the trap: these were only the planes that survived. Planes hit in other places, such as the engines, simply never made it home to be counted, so the “clean” areas on the returning planes were the places where a hit was fatal. Wald built mathematical methods to estimate this hidden damage, and the version people retell today is a simplified legend of his much more technical work. The lesson is real, though. This blind spot is called survivorship bias: we study the winners and forget the ones that quietly disappeared.
Mangel & Samaniego, Journal of the American Statistical Association (1984)
Why it's cool Once you know it, you start spotting it everywhere, from “I never studied and still got an A” stories to the billionaire dropout myth, because you only ever hear from the planes that landed.
Read moreDouble Denim: The Jacket Made for a Singer Who Was Turned Away
Head-to-toe denim looks like a risky fashion dare, but it has a famous origin story. In May 1951 the singer Bing Crosby reportedly arrived at a Vancouver hotel in jeans and was initially refused a room because the clerk did not recognise him. Levi’s answered with a custom denim tuxedo jacket, complete with a label asking hotels everywhere to welcome the wearer. That one stunt turned “too casual for a hotel” into a style statement, and the look later picked up the nickname “Canadian tuxedo”, although the name only seems to have appeared decades later. The trick that makes double denim work is contrast on purpose: two clearly different washes, such as a dark jacket with light jeans, look chosen, while two almost-matching shades look like a mistake. Or go all in on one wash, and it reads as a deliberate set.
UBC Dictionary of Canadian Hotel Practice
Read moreSunlight Spent Tens of Thousands of Years Getting Out of the Sun
Light needs only about eight minutes to travel from the Sun to your face. But the light you feel today was made deep in the Sun’s core, and from there it had to fight its way out. The inside of the Sun is so crowded that each particle of light is absorbed and re-emitted again and again, wandering in a random zigzag instead of a straight line. Estimates for the escape trip vary a lot with the assumptions, from roughly 10,000 to well over 100,000 years. If light could fly straight out, it would take only a couple of seconds.
Tell someone The sunlight on your skin took eight minutes to reach Earth, after taking tens of thousands of years just to get out of the Sun.
Scientists Painted Cows Like Zebras, and the Flies Stayed Away
Zebras might wear stripes partly to avoid being bitten, because biting flies seem to land less on striped surfaces. To test the idea, researchers in Japan painted black-and-white stripes on Japanese Black cattle, painted only black stripes on others, and left some unpainted. The cows with black-and-white stripes attracted significantly fewer biting flies, around half as many by the team’s count, and they also needed to flick and stamp less. The study was small, with only six cows, and the paint does not last long, so it is a clue rather than a farming miracle. Researchers think the stripes may confuse the flies’ vision as they come in to land.
Tell someone Japanese scientists painted zebra stripes on cows and the flies landed on them about half as often.
The Smell of Old Books Is Paper Slowly Breaking Down
Paper is made largely of cellulose and a tough plant material called lignin, and over time both slowly break down. As they do, they release tiny amounts of airborne chemicals, and your nose picks up the mix. Benzaldehyde adds a hint of almond, and vanillin adds a vanilla-like note, while other compounds make the smell more musty or grassy. Researchers at University College London even built a “historic book odour wheel” to describe these scents, partly to help conservators judge how a book is ageing. In a sense, a bookshop is a library of slow chemical reactions.
Tell someone That lovely old-book smell is literally paper decomposing and releasing vanilla and almond chemicals.
l’embarras du choix
lahm-bah-RAH dü SHWAH · noun phrase
The difficulty of having so many good options that it is hard to pick one; literally, “the embarrassment of choice”.
« Devant tous ces romans à la librairie, j’avais l’embarras du choix. »
Faced with all these novels in the bookshop, I was spoilt for choice.
In older French, embarras meant an obstacle or a clutter, not shyness, which is why the phrase feels like a pleasant traffic jam. The English “embarrassment of riches” comes from a French play of 1726, L’Embarras des richesses. Use it when you are happily stuck, in front of a menu, a playlist or a wardrobe.
The Case of Three Stories and One Truth
The silver trophy from the chemistry club’s display shelf was gone on Monday morning, and only three students had been in the lab after class: Ines, Jo and Kit. Their teacher, Ms Adeyemi, announced something unusual: exactly one of the three would tell the truth, and the other two would lie, and the thief was one of them. Ines said, “I did not take it.” Jo said, “Kit took it.” Kit said, “Jo is lying.”
Who took the trophy?
Reveal the answer
Ines. Jo and Kit contradict each other, because if Jo is telling the truth then Kit is lying, and if Jo is lying then Kit is telling the truth, so one of them is always the truthful one. That uses up the only truth allowed, so Ines must be lying when she says she did not take it, which makes her the thief.
Survivorship bias is why every “I never studied and still passed” story comes from a person who passed. The ones who failed are busy not telling stories.
Sunlight takes eight minutes to get from the Sun to Earth, but tens of thousands of years to leave the Sun. It is basically me trying to say goodbye at a family party.
Scientists painted zebra stripes on cows to keep flies away. So yes, bold fashion choices can be pest control.
Ask for Advice, and You’ll Look More Capable, Not Less
Many of us avoid asking for help because we worry it will make us look clueless. Researchers Alison Wood Brooks, Francesca Gino and Maurice Schweitzer tested this in a set of experiments published in Management Science in 2015. They found that people tended to rate someone who asked them for advice as more competent, especially when the task was hard. The effect was strongest when the person asked was someone who actually knew the topic. The reason it works is that a good question shows you understand the problem well enough to know where you are stuck, and it also flatters the other person’s expertise. The catch is to ask a specific question, such as “what would you try next?” rather than “can you just do it?”
Try it today Pick one thing you are stuck on, choose one person who knows about it, and ask them one specific question that starts with “What would you do if…”.
Spotlight
Tilly Edinger
Tilly Edinger (1897–1967) founded paleoneurology, the study of the brains of extinct animals, by realising that the hollow stone casts inside fossil skulls preserve the shape of the brain. She fled Nazi Germany in 1939–40 and continued her work at Harvard, where her 1948 study of horse brains showed that bigger, more folded brains evolved separately in different animal lines. In 1963 she became the first woman president of the Society of Vertebrate Paleontology. More →