Excerpt from Decisive (2013) by Chip Heath and Dan Heath

Kevin Dunbar set out to understand how scientists think. How do they solve problems? Where do their breakthroughs come from? So, like a war reporter embedding himself with an army unit, Dunbar spent a year alongside the scientists in four leading molecular biology laboratories, watching and recording their work.

What Dunbar discovered, after countless hours of eavesdropping and interviewing and synthesizing, was that one of the reliable but unrecognized pillars of scientific thinking is the analogy.

When the scientists ran into problems with their experiments, a common day-to-day experience, they would often benefit from a “local analogy”: a comparison to a very similar experiment with a similar organism. So if one scientist was bemoaning a failed experiment with the phage virus, a colleague might share an example of how he tweaked an experiment to overcome a similar problem. “This type of reasoning occurred in virtually every meeting I observed, and often numerous times in a meeting,” said Dunbar.

Other times, the scientists were struggling with a bigger problem. In those discussions,

Dunbar found, the scientists often switched from using local analogies to what he called “regional analogies.” These typically involved another organism that had a family relationship with the organism being studied. A scientist trying to understand how a new virus replicates, for instance, might work through an analogy from a better-known virus such as smallpox.

Dunbar said “the use of analogies is one of the main mechanisms for driving research forward.” And the key to using analogies successfully, he said, was the ability to extract the “crucial features of the current problem.” This required the scientist to think of the problem from a more abstract, general perspective, and then “search for other problems that have been solved.”

When you use analogies—when you find someone who has solved your problem—you can take your pick from the world’s buffet of solutions. But when you don’t bother to look, you’ve got to cook up the answer yourself. Every time. That may be possible, but it’s not wise, and it certainly ain’t speedy.

A separate study of a medical plastics design group, conducted by Bo T. Christensen and Christian D. Schunn, found that the designers tapped a veritable circus of analogies, including zippers, credit cards, toilet paper, shoes, milk containers, Christmas decorations, water wheels, picture puzzles, Venetian blinds, and lingerie.

What we’re seeing here is that, when you’re stuck, you can use a process of “laddering up” to get inspiration. The lower rungs on the ladder offer a view of situations very similar to yours; any visible solutions will offer a high probability of success, since the conditions are so similar. As you scale the ladder, you’ll see more and more options from other domains, but those options will require leaps of imagination. They’ll offer the promise of an unexpected breakthrough—but also a high probability of failure. When you start looking for crossfertilization between the medical plastics domain and the world of lingerie, you’re likely to find yourself at a lot of dead ends (or perhaps with a very hard and uncomfortable bra).

For an example of laddering up, let’s imagine a junior high principal, Mr. Jones, who wants to speed up the lunch line in the school cafeteria. He figures if students spend less time waiting in line, they’ll have more time to go outside and get some activity before afternoon classes begin.

Given this goal, where can Jones look for options? The first answer, we know now, is that he should look locally. Are there bright spots in his own staff? Maybe one checkout line always seems to move faster than the others; Jones could study how the checkout clerk handles the process. (Perhaps, like the collectors at toll booths, she counts out common configurations of change in advance.) Jones could spread her approach to the remaining cashiers.

If there are no obvious bright spots, he can ladder up a couple of rungs and benchmark the practices of other schools in his city. If he strikes out again, he could keep laddering up. The next step might be to expand his search to any organization with a checkout process, from convenience stores to community pools. (These rungs of the ladder are akin to a scientist’s use of a “regional analogy”—learning from another organism that is similar to the one they study.)

As he climbed, he would broaden the definition of the problem. Instead of looking for people who have pioneered creative checkout solutions, he might hunt down people who excel at managing the flow of crowds: managers of sports stadiums, amusement parks, or shopping malls. (Could you learn something from Disney’s rollercoaster queues, for instance, that might be useful in a crowded lunchroom?)

Lexicon, perhaps the most famous “naming” firm in the world, excels at this process. In naming the processor that became the Pentium, they wanted names that suggested “speed,” so they laddered up past the domain of computer technology to consider any fast, highperformance product. One team, in fact, spent time studying the names of slalom race skis. (In the end, another analogy would prevail: The notion that the processor was a powerful “ingredient,” an essential element of the computer. Note the “-ium” ending to the “Pentium” brand name, making it sound like something from the Periodic Table of Elements.)

TO SEE HOW LADDERING UP can generate a truly novel option, consider the story of Fiona Fairhurst, a designer who’d been hired in 1997 by Speedo. She was given a crystal-clear mission: To design a swimsuit that would make swimmers faster.

Traditionally, swimsuits had evolved to become smoother, tighter, and skimpier, but Speedo had grown interested in new design approaches. Fairhurst, a swimmer herself, was unimpressed with Speedo’s early designs, so she began to seek out other sources of inspiration. “This is how my brain works,” she told Dick Gordon in a June 2012 interview. “If I’m going to make something that goes fast, I tend to look at everything that goes fast and the mechanisms that make things go fast. So I started looking at manmade objects like boats, torpedoes, space shuttles, everything.”

Fairhurst was laddering up. She’d redefined the problem from “a swimsuit that goes fast” to “anything that goes fast, especially in the water.” And that got her interested in animals who seemed to move faster in water than they ought to. Shortly thereafter, she had a fateful day at the Natural History Museum in London:

“It was one of those ‘eureka moments’ … [The guide from the museum] took me to the back rooms of the Natural History Museum, … It’s not where the public is allowed. And he had this huge metal tank, and he lifted it open, and inside was a 9foot shark. And he said to me, ‘Fiona, you need to touch his nose, touch his belly.’ … I was thinking, ‘What the heck am I doing?’

As I touched the nose, it was exceedingly rough, almost sharp. It’s made of this material like enamel, like our teeth, it’s called dermal denticle. … If you run your hand from nose to tail, it’s smooth, but a bit like any fish scale, if you run your hand backward, it’s sharp and it will cut your hand.

They sent a sample of the shark’s skin to a lab, which returned images of its rough and micro-grooved texture. The images sparked an insight for her: “For years many people thought smooth fabric was the key [to speed], but if you look at sharkskin and how rough it is, roughness is the actual key to making a fast fabric.” (Indeed, one Harvard scientist has conducted experiments showing that the shark’s rough denticles reduce drag and increase thrust.) Inspired, Fairhurst and her colleagues sampled over 1,000 different fabrics until they found one whose texture convincingly mimicked sharkskin.

Another, perhaps more important, change they made to the new swimsuit was inspired by an analogy to a man-made object, the naval torpedo. Unlike skimpy traditional suits, Fairhurst’s swimsuit covered much of the body, like a second skin. It was tight and restricting, which struck some athletes as uncomfortable at first, but Fairhurst said the effects were profound: “by compressing all your lumps and bumps, you can make a more torpedo-like shape thru the water.”

The Speedo team began to test the new suit with Olympic athletes. In one test leading up to the 2000 games in Sydney, Fairhurst worked with Jenny Thompson, an American swimmer who’d already won medals in the 1992 and 1996 Games. As Thompson’s coach timed her, she swam 50 meters once with her own suit and once with Fairhurst’s new creation.

As Fairhurst recalled, when Thompson emerged from the pool, she said, “I hate this suit, it feels horrible.” Meanwhile, her coach, staring at the timer, was incredulous. Thompson’s time with the suit had been close to her world-record pace, even though she had started her swim by merely pushing off the wall with her feet rather than diving in at full speed. He told her, “A world record isn’t easy … so don’t rule out the suit!”

In test after test, the new suit, which came to be called the Fastskin, consistently outperformed its predecessors. Next came a regulatory hurdle: For the suit to be used by swimmers in the Olympics, it had to be approved by FINA, the international governing body for the sport of swimming. Fairhurst was surprised when FINA officials objected to the suit on aesthetic grounds.  “One of the things that they felt gave them very good TV coverage was the fact that it was beautiful people in swimsuits … a bit like the Baywatch mentality.” FINA’s leaders were worried that her suit was hiding too much flesh!

To her relief, FINA overcame these anxieties and approved the suit, and the Fastskin debuted at the 2000 Sydney Olympics. Its impact was immediate and dramatic: An astonishing 83% of the medals were won by swimmers who wore it.

The very success of the Fastskin inspired controversy. Critics, including some Olympic swimmers, questioned whether the suits were giving athletes an unfair advantage.

Later evolutions of her original swimsuit—the successors to Fastskin—kept boosting swimmers’ performance, until finally, FINA balked, banning certain fabrics and styles beginning in 2010.

Fairhurst’s laddering had produced a competitive advantage so strong that it had to be banned to keep the playing field level.