The Improbability Principle: Rare events and coincidences happen all the time.

Five Reasons Why Absurdly Improbable Things Happen All the Time

The state of the universe.
Feb. 12 2014 12:59 PM

It’s Not Actually a Miracle

Five reasons why absurdly improbable things happen all the time.

roulette wheel.
Landing on black 26 times in a row? It's bound to happen sooner or later.

Photo by William Thomas Cain/Getty Images

The newspaper notice said that Frank Hughes, of Hilda Street, Darlington, in the United Kingdom, had died on Aug. 1 at the age of 80, and gave the time and place of the funeral ceremony. Several of his friends and workmates turned up to pay their respects, and they joined the family and other mourners afterward.

So imagine the shock Frank’s friends must have felt when, just an hour later, they saw him walking along the street toward them.

It turned out that the newspaper notice announcing 80-year-old Frank’s funeral wasn’t referring to the retired bus driver and D-Day veteran his friends thought it was. It was actually referring to another Frank Hughes of the same age and from the same town. That Frank Hughes was an ex-merchant-seaman, which explained why the family members weren’t surprised to see people they didn’t recognize at the funeral.


And then there were the two Franz Richters, both 19, both volunteers in the Austrian Transport Corps after World War I, both born in Silesia, and both suffering from pneumonia, who were admitted to the same hospital at the same time.

At a more elevated level, in the 1700s, when Samuel Johnson (who’s been described as “arguably the most distinguished man of letters in English history”) was invited to write a translation of a volume on the administrative apparatus of the Roman Catholic Church, it was found that another Samuel Johnson, this one the Librarian of St. Martin’s in the Fields, had also been invited to translate the work. A literary skirmish took place between the two Samuel Johnsons, with the unfortunate consequence that neither carried out the translation.

Extraordinary coincidences, perhaps. But highly unlikely? Not when looked at from the right perspective. And that perspective is given in my new book, The Improbability Principle. It tells us that extremely improbable events are commonplace. Since that may sound like a contradiction, let’s take a closer look.

The improbability principle is composed of five laws, analogous to the four laws of thermodynamics or Newton’s three laws of motion. These laws, the law of inevitability, the law of truly large numbers, the law of selection, the law of the probability lever, and the law of near enough, explain exactly why we should expect to encounter highly unlikely events, and indeed why we should expect to do so on a regular, even frequent, basis. Any one of the laws acting by itself can lead to a highly improbable event—like people winning the lottery twice, or 26 black numbers coming up one after another in roulette. (The details of these as well as many other apparently extraordinarily unlikely events are given in my book.) But the impact of the principle gets even stronger when the laws intertwine and work together.

When that happens, we see people being struck by lightning—not just once but, despite the old adage, twice and then time after time. We see the same lottery numbers coming up in two consecutive weeks. We see apparent manifestations of extrasensory perception, people narrowly avoiding disaster after disaster, financial crashes that shouldn’t happen in a billion years, and countless other extraordinary events. We also learn how tipsters correctly predict stock market moves, how you can increase your chance of winning the lottery, why the student who comes out on top today is less likely to do so tomorrow, and how psychics can make correct predictions. They are all a consequence of the solid mathematics embodied in the improbability principle.

Let’s take my opening theme of name coincidences further. In fact, let me make it personal.

In 2012, when I checked into my hotel for the Royal Statistical Society’s conference in Telford, United Kingdom, I found that I was the second David Hand to check in. It wasn’t that I’d accidentally registered twice—there really was another David Hand in the hotel.

Now, most of the Google generation knows that there are others with the same name out there. After all, who among us has not succumbed to the temptation to search for our own names? I already knew of David Hand the former bishop of Papua New Guinea, and David Hand the former Disney animator. But I also knew that both of them were dead, and I certainly wasn’t expecting to meet any of my namesakes. So, when I checked into the hotel, my first thought was that such encounters between people with the same name must be incredibly rare. Highly improbable events, right?

But then I recalled the improbability principle.

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