How to Ignite Breakthroughs with Thought Experiments

When I examine myself and my methods of thought, I come to the conclusion that the gift of fantasy has meant more to me than my talent for absorbing positive knowledge.

—ALBERT EINSTEIN

WHAT WOULD HAPPEN if I chased after a beam of light? A sixteen-year-old Albert Einstein pondered this question after he had run away from his unimaginative German school that emphasized rote memorization at the expense of creative thinking. His destination was a reformist Swiss school founded on the principles of Johann Heinrich Pestalozzi, who championed learning through visualization.

While there, Einstein put Pestalozzi’s principles into action and visualized himself chasing after a beam of light. He believed that if he managed to catch up with it, he would observe a frozen light beam. This belief, which conflicted with Maxwell’s equations on the oscillations of electromagnetic fields, caused Einstein what he described as “psychic tension.” The resolution of this psychic tension took him a decade—and eventually produced the special theory of relativity.

It was another question that later produced the general theory of relativity: Does a person who falls freely in an enclosed chamber feel his own weight?

This question—which Einstein later called “the happiest thought of my life”—occurred to him while he was daydreaming at his desk in a Swiss patent office. Einstein’s job as a patent clerk had trained him well for visualization. Evaluating patent applications required him to picture how each invention would work in practice. Picturing his new thought experiment, he concluded that the man falling freely would not feel his own weight and would instead think he was floating in zero gravity. This conclusion, in turn, led him to another major discovery: Gravity and acceleration are the same.

Einstein credits these thought experiments (or what he would have called Gedankenexperimente) for virtually all his breakthroughs. Over his lifetime, he would visualize “lightning strikes and moving trains, accelerating elevators and falling painters, two-dimensional blind beetles crawling on curved branches,” among many others. With his mind at play, Einstein upended entrenched assumptions in physics, cementing himself as one of the most popular scientific figures in the public imagination.

This chapter is about the power of thought experiments. You’ll discover why the key to supercharging your creativity is to do nothing at all and how most work environments sabotage, rather than boost, people’s creative potential. You’ll learn why you should compare apples and oranges and what made Newton the least favorite professor on campus. I’ll reveal how a simple question from an eight-year-old created a billion-dollar author and what a revolutionary running shoe and one of the greatest rock songs of all time have in common. Along the way, you’ll meet scientists, musicians, and entrepreneurs who have used a technique called combinatory play to produce breakthrough works, and you’ll learn how to apply it in your own life.

The Laboratory of the Mind

Although they’re associated with Einstein in popular culture, thought experiments date back at least to the ancient Greeks. Since then, they have spread across disciplines, generating breakthroughs in philosophy, physics, biology, economics, and beyond. They have powered rockets, toppled governments, developed evolutionary biology, unlocked mysteries of the cosmos, and created innovative businesses.

Thought experiments construct a parallel universe in which things work differently. They require us, as philosopher Kendall Walton explains, to “imagine specific fictional worlds, as kinds of situational setups that when you run, perform, or simply imagine them, lead to specific results.” Through thought experiments, we transcend everyday thinking and evolve from passive observers to active interveners in our reality.

If the brain had a tail, thought experiments would make it wag.

There are no precise spells for conducting thought experiments or secret recipes you can copy. Formulas and rules are antithetical to first-principles thinking, so every well-crafted thought experiment is unique in its own way. In this chapter, I’ll help you create the right conditions for thought experiments, but my intention is to guide, not to constrain.

When we think of scientists, we often imagine lab-coated brainiacs poring over state-of-the-art microscopes in fluorescent-lit labs. But for many scientists, the laboratory of the mind is far more important than the laboratory of the physical world. As rockets fire spacecraft, thought experiments fire our neurons.

Consider Nikola Tesla, the famous Serbian American inventor. His thought experiments powered his imagination, producing the alternating-current system that now powers our lives. Tesla built and tested inventions all in his mind. “Before I put a sketch on paper, the whole idea is worked out mentally,” he explained. “I do not rush into actual work. When I get an idea, I start at once building it up in my imagination. I change the construction, make improvements and operate the device in my mind. It is absolutely immaterial to me whether I run my turbine in thought or test it in my shop.”

Leonardo da Vinci did the same. He famously used his notebooks for thought experiments, sketching various engineering designs he formulated in his mind—from flying machines to churches—instead of physically constructing them.

Let’s pause there for a moment. As shocking as it sounds, we can generate breakthroughs simply by thinking. No Google. No self-help books. No focus groups or surveys. No advice from a self-proclaimed life coach or an expensive consultant. No copying from competitors. This external search for answers impedes first-principles thinking by focusing our attention on how things are rather than how they could be.

Thought experiments take this external inquiry and turn it inward—just you and your imagination. “Pure thought,” Einstein said, “can grasp reality.” Thoughts can disprove an argument, show why something will or won’t work, and illuminate the way forward—all without a single physical experiment.

Consider this example. In a world with no air resistance, if you simultaneously drop a heavy bowling ball and a light basketball from the same height, which one would strike the ground first? Aristotle believed that the heavy object would fall faster than the lighter one. This theory persisted for two millennia, until an Italian scientist named Galileo Galilei entered the scene. Galileo was born a misfit in a world of conformists. He challenged tyrannical dogma across diverse disciplines, most famously championing heliocentrism, which placed the Sun, rather than the Earth, at the center of the solar system.

Galileo also took on Aristotle’s theory. The Italian didn’t believe that acceleration increased with mass. So he climbed to the top of the Leaning Tower of Pisa, dropped two objects of different weights, and chuckled in delight while calling Aristotle funny names when both objects hit the ground at the same time.

Except he didn’t.

This entire episode turned out to be a myth manufactured by Galileo’s earliest biographer. Most contemporary historians agree that Galileo instead conducted a thought experiment—not a physical one. He imagined a heavy cannonball and a light musket ball chained together to form a single, combined system to be dropped at the same time. If Aristotle were right, the attached system should fall faster than the heavy cannonball alone because the combination weighs more. But it would also mean the light musket ball in the attached system should fall slower than the heavy cannonball. In other words, if Aristotle’s theory is correct, the light musket ball should act as a drag on the combined system, causing it to fall slower than the heavy cannonball alone.

Both statements can’t be true: The attached system can’t fall both faster and slower than the heavy cannonball on its own. The thought experiment reveals a contradiction in Aristotle’s theory and obliterates it. Through thought alone and without spending a dime, a venerated theory was cast aside, making room for a new one.

Galileo also devised another famous thought experiment to demonstrate how perspective shapes our understanding of motion. He asked us to imagine a scientist performing experiments inside a windowless ship sailing on a perfectly smooth sea. If the scientist drops a ball from the mast, it falls straight down to his feet—just as it would on land. Fish swimming alongside the ship, however, see the ball’s path as a long diagonal line, because the ship and everything in it moves forward while the ball falls. Neither observer is wrong; they simply inhabit different frames of reference. What the scientist perceives as stationary reality is, in truth, a shared motion he has ceased to notice. This mental exercise helped Galileo argue that the Earth itself could be moving without our feeling it—a radical idea that supported Copernicus’s sun-centered model.

Centuries later, Einstein extended this line of thinking with his own perspective-shifting thought experiment. Imagine you are standing near a train track as a train speeds past. Just as the train’s midpoint reaches you, lightning strikes both its front and rear ends simultaneously. Because both flashes are the same distance from you, you see them at the same instant and correctly conclude the strikes were simultaneous. Now imagine your friend sitting at the midpoint of the moving train. From her perspective, the train is stationary and the landscape is rushing backward. Because she is moving toward the spot where the front lightning struck, the light from that strike reaches her slightly sooner than the light from the rear strike. She therefore perceives the front strike happening first. According to the laws of physics, both of you are right. There is no single, absolute “now” that governs all observers—time itself is relative.

These thought experiments reveal a profound truth: our perspective is very much unique to us, and none of us perceives reality in totality without doing a little work. In the day-to-day world, this means you are seeing what nobody else sees but also that you do not automatically, unconsciously see through the eyes of others. Is it any wonder we make suboptimal decisions? Thought experiments force us to adopt multiple vantage points, making them rigorous applications of the scientific method to determine what we can infer from what we can imagine.

Centuries later, Galileo’s falling-objects thought experiment was put to the test on the Moon. In 1971, during the Apollo 15 mission, astronaut David Scott dropped a hammer and a feather from the same height while standing on the Moon’s surface. Both fell at the same rate and struck the lunar surface at the same time. The official science report described the result as “reassuring” in light of “both the number of viewers that witnessed the experiment and the fact that the homeward journey was based critically on the validity of the particular theory being tested.”

Curiosity is a crucial ingredient in any thought experiment. It’s what propelled Galileo to pose his thought experiments, and Scott to test their validity on the lunar surface. Yet for much of society, curiosity isn’t a great virtue, but is a killer vice.

Curiosity Killed Schrödinger’s Cat

Can a cat be alive and dead at the same time? This was the question that Austrian physicist Erwin Schrödinger asked through a famous thought experiment. His goal was to stretch the limits of what’s known as the Copenhagen interpretation of quantum mechanics. According to the interpretation, quantum particles (such as atoms) exist in a combination—or superposition—of different states. Put differently, a quantum particle can be in two states or in two places simultaneously. It’s only when someone observes the particle that it collapses into one of many possible states.

Schrödinger took the Copenhagen interpretation and applied it to a cat. In his thought experiment, a cat is placed inside a sealed box with a vial of poison that will be randomly released when a radioactive substance inside the box decays. If you buy the Copenhagen interpretation, before the box is opened, the cat is in a superposition: It’s both alive and dead. Only when someone opens the box does the cat collapse into one of these two realities.

This result, of course, is wildly counterintuitive. But it was precisely the point of Schrödinger’s thought experiment—to contradict, to provoke, and to disprove the Copenhagen interpretation by taking it to its logical extremes.

But there’s another takeaway from this thought experiment. It wasn’t the poison that killed the cat. It was the act of curious observation, of not minding your own business, of opening the box to see what’s inside the same way a child might sneak to open presents the night before Christmas.

There’s an idiom in the English language dedicated to this idea: Curiosity killed the cat. Or as Russians say with far more dramatic flair, “The nose of curious Barbara was torn off at the market.”

These idioms, according to the ever-reliable Wikipedia, are “used to warn of the dangers of unnecessary investigation or experimentation.” Curiosity, in cats or in Russian market-goers, isn’t just annoying or inconvenient. People who ask questions or pose thought experiments aren’t just pesky troublemakers who can’t be satisfied with the status quo. They’re downright dangerous. As the renowned Hollywood producer Brian Grazer and his coauthor Charles Fishman write, “The child who feels free to ask why the sky is blue grows into the adult who asks more disruptive questions: Why am I the serf and you the king? Does the sun really revolve around Earth? Why are people with dark skin slaves and people with light skin their masters?”

We discourage curiosity also because it requires an admission of ignorance. Asking a question or posing a thought experiment means that we don’t know the answer, and that’s an admission that few of us are willing to make. For fear of sounding stupid, we assume most questions are too basic to ask, so we don’t ask them.

What’s more, in this era of “move fast and break things,” curiosity can seem like an unnecessary luxury. With an inbox-zero ethos and an unyielding focus on hustle and execution, answers appear efficient. They illuminate the path forward and give us that life hack so we can move on to the next thing on our to-do list. Questions, on the other hand, are exceedingly inefficient. If they don’t yield immediate answers, they’re unlikely to get a slot on our overloaded calendars.

At best, we pay lip service to curiosity but end up discouraging it in practice. Businesses hold a “creativity day” to foster innovation—complete with a PowerPoint presentation and an expensive outside speaker—but go back to business as usual for the remaining 364 days. Employees are rewarded for staying the course rather than questioning it. According to a survey of workers in sixteen industries, “while 65% said that curiosity was essential to discover new ideas, virtually the same percentage felt unable to ask questions on the job.” Although 84 percent in the same survey said their employers encouraged curiosity on paper, 60 percent encountered barriers to it in practice.

Instead of making curiosity the norm, we wait until a crisis occurs to become curious. Only when we’re laid off do we begin to ponder alternative career paths. And only when our business is disrupted by a young, scrappy, and hungry competitor do we gather the troops to spend a few futile hours to “think outside the box.”

For answers, we rely on the same methods, the same brainstorming approaches, and the same stale neural pathways. It’s no wonder that the resulting innovations aren’t innovations at all. They’re at best insignificant deviations from the status quo. Look at any monstrous company or bloated bureaucracy collapsing under its own weight, and you’ll find a historical lack of curiosity.

Fear of the outcome is another reason we shun curiosity. We don’t ask hard questions when we’re afraid of what we might find (which is why people are reluctant to visit their doctor when they fear the diagnosis). Worse, we’re afraid that we may not find anything at all—that our inquiry led us nowhere—turning this whole thought-experiment business into a gigantic waste of time.

We also assume that thought experiments require complex mental gymnastics or divine inspiration. We tell ourselves that someone far smarter than us would have already posed the question if it were worth asking.

But geniuses don’t have a monopoly on thought experiments. There are no chosen few. You don’t need Einstein’s electrified head of hair to conduct thought experiments. It may not feel like it, but we’re all experimenters at heart—walking repositories of epiphanies hidden in our subconscious.

Seemingly unnecessary investigation and experimentation are precisely what you need to uncover those epiphanies. George Bernard Shaw once said, “Few people think more than two or three times a year. I’ve made an international reputation for myself by thinking once or twice a week.” As Shaw knew, hustle and creativity are antithetical to each other. You can’t generate breakthroughs while clearing out your inbox. You must dig the well before you’re thirsty and become curious now—not when a crisis inevitably presents itself.

Curiosity may have killed Schrödinger’s cat. But it just might save you.

A Lifelong Kindergarten

“Why can’t I see the picture now?” It was 1943, and Edwin Land was vacationing with his family in Santa Fe, New Mexico. Land, the cofounder of Polaroid and a camera enthusiast, was taking photos of his three-year-old daughter, Jennifer. Back then, there was no instant photography. The film had to be developed and processed in a darkroom before the photos could see the light of day—a turnaround time of several days. Although there are conflicting reports of what exactly happened, according to one popular account, a question that the precocious Jennifer asked her father changed everything.

“Why can’t I see the picture now?” Land took this question to heart. But he faced a big constraint. A huge darkroom couldn’t fit inside a small camera. He set out for a long walk to ponder the problem and came up with a thought experiment. What if the camera carried a small reservoir containing the chemicals used to develop film in a darkroom? The chemicals would be spread over a negative film and released onto the positive layer, producing the final image.

It took several years to perfect the technology, but the thought experiment eventually led to the invention of instant photography. With the new technology, only seconds, not days, would pass between the click of the shutter and a physical photo in your hands.

Although thought experiments don’t come naturally to most adults, we mastered them as children. Before the world stuffed us with facts, memos, and right answers, we were moved by genuine curiosity. We stared at the world, wrapped in awe, and took nothing for granted. We were blissfully unaware of social rules and viewed the world as our very own thought experiment. We approached life not with the assumption that we knew (or should know) the answers, but with the desire to learn, experiment, and absorb.

A favorite example of mine is about a kindergarten teacher who was walking around the room to check each child’s work as they drew pictures. “What are you drawing?” he asked one student. The girl said, “I’m drawing God.” The teacher was shocked at this deviation from the standard curriculum. He said, “But no one knows what God looks like.” The girl replied, “They will in a minute.”

Children intuitively grasp one cosmic truth that eludes most adults: It’s all just a game—a big, marvelous game. In the popular children’s book Harold and the Purple Crayon, the four-year-old protagonist has the power to create things just by drawing them. There’s no path to walk on, so he draws a path. There’s no moon to light his path, so he draws the moon. There are no trees to climb on, so he draws an apple tree. Throughout the story, his imagination brings things into existence.

Thought experiments are your very own reality-distortion field, your choose-your-own-adventure game—your purple crayon.

The purple crayon was Einstein’s favorite scientific tool, one that he carried with him even as an adult. As he wrote to a friend, “You and I never cease to stand like curious children before the great mystery into which we were born.” Centuries earlier, Isaac Newton purportedly used similar words in describing himself as “a boy playing on the seashore… whilst the great ocean of truth lay all undiscovered before me.”

Although Einstein and Newton managed to retain their childlike curiosity, it is beaten out of most people. Our conformist education system, designed to churn out industrial workers, is partly to blame (“No one knows what God looks like”). Our natural curiosity is also suppressed by busy, well-meaning parents who believe that everything important has already been settled. One can imagine an annoyed father in Edwin Land’s place dismissing his daughter’s question as absurd (“Patience, Jennifer! Learn to wait for the photo”). Or a busy mother missing the genius in sixteen-year-old Einstein’s beam-riding experiment (“Go back to your room, Albert. And stop the crazy talk”).

Over time, as we settle into adulthood, as student loans and mortgages begin to mount, our curiosity is replaced by complacency. We view intelligent urges as a virtue and playful urges as a vice.

But play and intelligence should be complements, not competitors. Play, put differently, can be a portal to intelligence. In his seminal article “The Technology of Foolishness,” James March writes that “playfulness is a deliberate, temporary relaxation of rules in order to explore the possibilities of alternative rules.” He argues that individuals and organizations “need ways of doing things for which they have no good reason. Not always. Not usually. But sometimes.” Only by taking a playful attitude toward our own beliefs can we challenge and change them.

The operative word in a thought experiment is experiment. This framing should lower the stakes. A thought experiment sets up a sandbox in the controlled environment of your mind. If it doesn’t work, nothing bad happens. There’s no collateral damage or spillover effects. At the initial stage, you’re not aiming for implementation—let alone perfection—so you’re less likely to get hamstrung by your assumptions, biases, and fears.

Recapturing our childlike curiosity can boost originality—and there’s plenty of research to back this up. Yet being told to think like a child can feel like being ordered to stay dry in a thunderstorm.

Here’s the good news: You can capture a childlike curiosity without physically regressing to your childhood or developing Peter Pan syndrome. Reconnecting with your inner child might be as easy as pretending to be a seven-year-old. This suggestion sounds bizarre, but it works. In one study, when participants were instructed to imagine themselves as seven-year-olds with free time, they performed better in objective tests of creative thinking. For this reason, the MIT Media Lab—devoted to “the unconventional mixing and matching of seemingly disparate research areas”—has a section called Lifelong Kindergarten.

Minds are far more malleable than we assume. If we pretend that life is one long kindergarten, our minds just might follow.

AT THIS STAGE, you might be wondering, if the thought experiment doesn’t make sense, if it more properly belongs in a children’s game, what’s the point? If the thought experiment can’t be implemented, what—if anything—separates it from useless fantasy?

The purpose of a thought experiment isn’t to find the “right answer”—at least not initially. This isn’t like your high-school chemistry class, where the outcome of each experiment was predetermined, leaving no room for curiosity or unexpected insights. If you didn’t get the right result, you would be stuck in the lab fiddling with test tubes and beakers, while your classmates trekked off to the movies. The point of Einstein’s thought experiment wasn’t to figure out a way to actually ride next to a light beam. Rather, it was to ignite a process of open-minded inquiry that can—and often did—result in unexpected major insights.

Pursuing a thought experiment—even one that leads nowhere—can lead to breakthroughs. Fantasies, as Walter Isaacson writes, can be “paths to reality.” It’s a little like driving from New York to Hawaii. Impossible? Yes. Will you discover profound new insights along the way before you hit the giant practical constraint that’s the Pacific Ocean? Absolutely. The goal is to jolt you out of your autopilot mode, keeping your mind receptive to possibilities.

Remember, the thought experiment is the starting point, not the end. The process is messy and nonlinear. And the answer, as we’ll see in the next section, will often come when you’re least expecting it.

Get Bored More Often

I couldn’t remember the last time I was bored.

I had just woken up and grabbed my phone to take my morning dose of digital notifications. As I was about to start scrolling through my various feeds, I had an epiphany.

I couldn’t remember the last time I was bored.

Along with my VHS player and Bon Jovi cassettes, boredom had become a relic of the past. Gone were the days when I would lie awake in bed in the morning, bored out of my mind, and daydream for a while before deciding to immerse myself into reality. I would no longer twiddle my thumbs while waiting for a haircut or strike up a conversation with a stranger waiting in line at a coffee shop.

I viewed boredom—which I define as large chunks of unstructured time free of distractions—as something to be avoided. Boredom evoked memories of getting chastised by teachers for daydreaming. Boredom, for me, was a bitter cocktail of agitation, impatience, and despair. I assumed that only boring people got bored, so I filled—no stuffed—every moment of my day with activity.

I know I’m not alone here. On a typical day, we switch from one form of social media to the next, check our email, catch up on the news—all within a span of twenty minutes. We prefer the certainty of these distractions over the uncertainty of boredom (I don’t know what to do with myself, and I’d rather not find out). In a 2017 survey, roughly 80 percent of Americans reported that they spent no time whatsoever “relaxing or thinking.”

During rare moments of tranquility, we feel almost guilty. As notifications scream their hundred-decibel sirens for attention, we feel compelled to take a furtive glance at them so we don’t miss out. Rather than being proactive, we spend most of our days—and our lives—playing defense. We self-soothe with the same distractions that ultimately make us feel worse.

Our responses stoke the fire, rather than put it out. Each email we send generates even more emails. Each Facebook message and tweet gives us a reason to return. It’s a Sisyphean torture, endlessly rolling a boulder up an impossible hill.

Yet we prefer this torture over boredom. In a 2014 study, researchers placed college-age participants in a room, removing all their belongings. They left the participants to their own devices and told them to spend time with their thoughts for fifteen minutes. I know, fifteen minutes—yikes!—but that’s why the researchers gave the internet-bred participants a choice: If they wanted, instead of losing themselves in thought, the students could self-administer an electric shock by pressing a button. In the study, 67 percent of men and 25 percent of women chose to shock themselves instead of sitting undisturbed with their thoughts (including one person who delivered a whopping 190 shocks to himself during the fifteen-minute period).

A shocking thought indeed.

Boredom, in other words, is now an endangered state. This isn’t an innocuous development. Without boredom, our creativity muscles begin to atrophy from disuse. “We are drowning in information,” biologist E. O. Wilson said, “while starving for wisdom.” If we don’t take the time to think—if we don’t pause, understand, and deliberate—we can’t find wisdom or form new ideas. We end up sticking with the first solution or thought that pops into our mind, instead of staying with the problem. But problems worth solving don’t yield immediate answers. As author William Deresiewicz explains, “My first thought is never my best thought. My first thought is always someone else’s; it’s always what I’ve already heard about the subject, always the conventional wisdom.”

We appear to be deferring life when we get bored, but it’s quite the opposite. In one study, two British researchers culled through decades of research, concluding that boredom should “be recognized as a legitimate human emotion that can be central to learning and creativity.” Falling into boredom allows our brain to tune out the external world and tune into the internal. This state of mind lets loose the most complex instrument known to us, switching the brain from the focused to the diffused mode of thinking. As the mind begins to wander and daydream, the default mode network in our brain—which, according to some studies, plays a key role in creativity—lights up.

As the saying goes, it’s the silence between the notes that makes the music.

Isaac Newton was “the least popular professor” on campus because “he’d stop in the middle of a lecture with a creative pause that could extend for minutes,” while his students waited for him to return to earth. During that pause, nothing appeared to be happening, but appearances deceive. Even when it’s idling, the brain is still active. “When you’re staring into space,” Alex Soojung-Kim Pang writes, “your brain consumes only slightly less energy than it does when you’re solving differential equations.”

So where does all that energy go? Your mind may seem to be drifting from one irrelevant topic to the next, but your subconscious is hard at work, consolidating memories, making associations, and marrying the new with the old to create novel combinations. The phrase unconscious mind is an insult to a part of our brain that does so much work behind the scenes.

When we sit still, we turn into a magnetized rod that attracts ideas. This is why phrases like epiphany, flash of light, or stroke of genius are often used to describe the eureka moment—Greek for “I’ve found it.” Ideas seem to explode into life during slack times, not during hard labor. Einstein was daydreaming when he had the revelation—a person who falls freely doesn’t feel his own weight—that led to the general theory of relativity. Danish physicist Niels Bohr literally dreamed up the structure of an atom when he envisioned himself “sitting on the sun with all the planets hissing around on tiny cords.” Archimedes’s famous eureka moment purportedly arrived when he was easing himself into a bath.

There’s a TV commercial where business executives squeeze themselves into a shower at work. One person asks, “Why are we meeting in the shower?” The boss replies, “Well, ideas always hit me in my shower at home.”

The idea-in-the-shower moment is cliché because it works. The fix for a defective mirror on the Hubble Space Telescope was dreamed up in the shower. Launched in 1990 to take high-resolution images of space, the telescope suffered from fuzzy vision because of a defective mirror. The fix required astronauts to reach deep into the telescope’s belly—not an easy feat for a satellite barreling around the Earth several hundred miles above its surface. While staying in a German hotel room, NASA engineer James Crocker stumbled on an adjustable shower head that extended or retracted to suit different heights. This observation was Crocker’s aha moment. He devised a solution to do the same for the Hubble by using automated arms that extended to reach into the seemingly inaccessible parts of the telescope.

These epiphanies appear effortless, but they’re the product of a long, slow burn. A breakthrough begins with asking a good question, laboring over the answer intensely, and being stuck in idleness for days, weeks, and sometimes years. Research shows that incubation periods—the time you spend feeling stuck—boosts the ability to solve problems.

As we saw earlier, Andrew Wiles became a mathematical celebrity after proving Fermat’s last theorem. Being stuck, according to Wiles, is “part of the process.” But “people don’t get used to that,” he says. “They find it very stressful.” When he got stuck—which was often—Wiles would stop, let his mind relax, and go for a walk by the lake. “Walking,” he explains, “has a very good effect in that you’re in this state of relaxation, but at the same time you’re allowing the sub-conscious to work on you.” As Wiles knew, a watched pot never boils. You often have to walk away from the problem—literally and metaphorically—for the answer to arrive.

A good footslogging is part of many scientists’ tool kit. Tesla dreamed up the alternating-current motor during a stroll through the Városliget, or city park, in Budapest. To ponder difficult problems, Darwin walked down a gravel path called the “sandwalk” near his home in Kent, kicking up stones along the way. The physicist Werner Heisenberg devised the uncertainty principle during a late-night walk through a park in Copenhagen. For two years, he had been frustrated that his equations could predict the momentum of a quantum particle but not its position. One night, he had an epiphany: What if there was no problem with the equations? What if the uncertainty was actually inherent in the nature of quantum particles? After walking with the question long enough, Heisenberg gradually walked into the answer.

Some scientists turn to music to tap into their subconscious. Einstein, for example, played his violin to decipher the music of the cosmos. As one friend recalled, “He would often play his violin in his kitchen late at night, improvising melodies while he pondered complicated problems. Then suddenly, in the middle of playing, he would announce excitedly, ‘I’ve got it!’ As if by inspiration, the answer to the problem would have come to him in the midst of music.”

Many creative people also embrace idleness to spur original thought. Ideas “come from daydreaming,” the author Neil Gaiman explains. They come “from drifting, that moment when you’re just sitting there.” When people ask Gaiman for advice on how to be a writer, his answer is simple: “Get bored.” Stephen King agrees: “Boredom can be a very good thing for someone in a creative jam.”

Getting bored landed a woman named Joanne her first publishing deal. In 1990, her train from Manchester to London was delayed for four hours. While waiting for the train, a story “came fully formed” into her mind—about a young boy who attends a wizardry school. That four-hour delay ended up being a blessing for Joanne “J. K.” Rowling, whose Harry Potter series captivated millions around the world.

In one sense, Rowling was lucky. Her epiphany arrived before smartphones did, so she didn’t have to play defense against notifications while waiting for her train. But the rest of us have to be proactive about building boredom into our lives. Bill Gates, for example, goes to a secluded Pacific Northwest cabin for weeklong retreats that he calls “Think Week” dedicated—you guessed it—to thinking without distractions. Phil Knight, the cofounder of Nike, had a designated chair in his living room for daydreaming.

Following in their footsteps, I decided to break my codependency with my phone and proactively rekindle my long-lost affair with boredom. I began deliberately building time into my day—an airplane mode of sorts—when I sit on my recliner doing nothing but thinking. I spend twenty minutes, four days a week, in the sauna, with nothing but a pen and paper in hand. Odd place for writing? Yes. But some of the best ideas in recent memory occurred to me in that solitary, stifling environment.

It sounds so simple. A walk in the park. A shower. Sitting in the sauna or a chair to daydream. But there’s no magic here—at least not in the Hogwarts sense. The magic is the intention of a designated time to pause and reflect—a moment for interior silence to oppose contemporary chaos.

In an age of instant gratification, this habit can sound a bit underwhelming. But creativity often comes as a subtle whisper—not a big bang. You must be patient enough to pursue the whisper and perceptive enough to receive it when it arrives. If you live with the question long enough, “you will gradually, without noticing it, one distant day live right into the answer,” as the poet Rainer Maria Rilke wrote.

The next time you feel boredom arising, resist the temptation to take a hit of data or do something “productive.” Boredom might just be the most productive thing you can do.

Boredom has another benefit. It allows your mind to freely associate and draw connections between drastically different objects—say, an apple and an orange.

Comparing Apples and Oranges

Many idioms in English have flummoxed me since I started learning the language in middle school. But one tops the list: comparing apples and oranges. The first time I heard the idiom in college, it stopped me in my tracks. I thought there’s more that unites apples and oranges than divides them. (At this point, dear reader, you may want to turn around and look away. I’m about to compare apples and oranges.) Both are fruits. Both are round(ish). Both have a slight tangy taste. Both are about the same size. And both grow on trees.

Scott Sanford of the NASA Ames Research Center took this comparison a step further. He used infrared spectrometry to compare a Granny Smith apple and a navel orange and showed that the spectra of the two fruits are strikingly similar. The study, with the tongue-in-cheek title “Apples and Oranges: A Comparison,” was published in the satirical scientific magazine Improbable Research.

Despite the similarities between apples and oranges, the idiom thrives because we’re terrible at seeing connections between seemingly dissimilar or unrelated things. In our personal and professional lives, we confine ourselves to comparing apples to apples and oranges to oranges.

Specialization is all the rage these days. In the English-speaking world, a generalist is a Jack or Jill of all trades, but the master of none. The Greeks caution that a person “who knows a lot of crafts lives in an empty house.” The Koreans believe a person of “12 talents has nothing to eat for dinner.”

This attitude comes at a cost. It stifles the cross-pollination of ideas from different disciplines. We remain in our humanities track or science track and shut off our minds to concepts from across the aisle. If you’re an English major, what use do you have for quantum theory? If you’re an engineer, why bother reading Homer’s Odyssey? If you’re a medical student, why study the visual arts?

That last question was the subject of a research study. Thirty-six first-year medical students were randomly split into two groups. The first group took six classes at the Philadelphia Museum of Art on observing, describing, and interpreting works of art. These students were compared with a control group that didn’t enroll in the art classes. Unlike the control group, the art-training group members significantly improved their observational skills—such as interpreting photographs of retinal disease—as measured in tests conducted at the beginning and the end of the study. “Art training alone,” the study suggests, “can help to teach medical students to become better clinical observers.”

Life, it turns out, doesn’t happen in compartmentalized silos. There’s little to be learned from comparing similar things. “To create,” biologist François Jacob said, “is to recombine.” Decades later, Steve Jobs echoed the same sentiment: “Creativity is just connecting things. When you ask creative people how they did something, they feel a little guilty because they didn’t really do it, they just saw something.… [T]hey’ve had more experiences or they have thought more about their experiences than other people.”

Put differently, it’s easier to “think outside the box” when you’re playing with multiple boxes.

Einstein called this idea “combinatory play,” which he believed is the “essential feature in productive thought.” Combinatory play requires exposing yourself to a motley coalition of ideas, seeing the similar in the dissimilar, and combining and recombining apples and oranges into a brand-new fruit. With this approach, the “whole becomes not only more than but very different from the sum of its parts,” as the physicist and Nobel laureate Philip Anderson explains.

To facilitate cross-pollination, renowned scientists often develop diverse interests. Galileo, for example, was able to spot mountains and plains on the Moon—not because he had a superior telescope, but because his training in painting and drawing enabled him to understand what the bright and dark regions on the Moon represented. Leonardo da Vinci’s inspiration for art and technology also came from the outside—in his case, nature. He instructed himself on subjects as diverse as “the placenta of a calf, the jaw of a crocodile, the tongue of a woodpecker, the muscles of a face, the light of the moon, and the edges of shadows.” Einstein’s inspiration for general relativity came from the eighteenth-century Scottish philosopher David Hume, who first questioned the absolute nature of space and time. In a December 1915 letter, Einstein wrote, “It is very possible that without these philosophical studies I can not say that [relativity] would have come.” Einstein was first introduced to Hume’s work through a group called the Olympia Academy, a group of friends dedicated to combinatory play who met in Bern, Switzerland, to discuss physics and philosophy.

In developing his theory of evolution, Darwin was inspired by two very different fields—geology and economics. In Principles of Geology, Charles Lyell argued in the 1830s that mountains, rivers, and canyons had been formed through a slow, evolutionary process that took place over eons as erosion, wind, and rain chipped away at the Earth. Lyell’s theory bucked conventional wisdom, which attributed these geological features solely to catastrophic or supernatural events like Noah’s flood. Darwin read Lyell’s book while sailing on the Beagle and applied the geological idea to biology. As rocket scientist David Murray explains, Darwin argued that organic material “evolves just as inorganic material does: with minute changes in each descendant that, over time, accumulate to form new biological appendages like eyes, hands, or wings.” Darwin also drew inspiration from the late-eighteenth-century economist Thomas Malthus. Malthus argued that humans tend to outgrow resources like food, creating a competition for survival. This competition, Darwin believed, drove the evolutionary process, leading the species best adapted to their environment to survive.

Combinatory play is also the hallmark of great musicians. The renowned record producer Rick Rubin tells his bands not to listen to popular songs while they produce an album. They’re “better off drawing inspiration from the world’s greatest museums,” Rubin says, “than finding it in the current Billboard charts.” For example, Iron Maiden’s music combines the unlikely elements of Shakespeare, history, and heavy metal. Queen’s “Bohemian Rhapsody,” considered one of the greatest rock songs of all time, is like a musical sandwich, blending an opening and closing ballad with hard rock and opera in the middle.

David Bowie was another master blender. When writing lyrics, he used a custom-developed computer program called the Verbasizer. Bowie would type up sentences from different sources—newspaper articles, journal entries, and the like—into the Verbasizer, which would cut them up into words and mix and match them. “What you end up with,” Bowie explained, “is a real kaleidoscope of meanings and topic[s] and nouns and verbs all sort of slamming into each other.” These combinations would then serve as inspiration for song lyrics.

Combinatory play has also produced many breakthrough technologies. Larry Page and Sergey Brin adopted an idea from academia—the frequency of citations to an academic paper indicates its popularity—and applied it to the search engine to create Google. Steve Jobs famously borrowed from calligraphy to create multiple typefaces and proportionally spaced fonts on the Macintosh. Netflix cofounder Reed Hastings was inspired by the subscription model used at his gym: “You could pay $30 or $40 a month and work out as little or as much as you wanted.” Frustrated by the big late fees he had incurred for renting Apollo 13, Hastings decided to apply the same model to video rentals.

Nike’s first running shoes were modeled after a common household appliance. In the early 1970s, University of Oregon running coach Bill Bowerman was looking for shoes that would perform well on different surfaces. At the time, Bowerman’s athletes would wear shoes with metal spikes, which lacked proper traction and would destroy the running surface.

One Sunday morning over breakfast, Bowerman’s eyes drifted toward an old waffle iron in the kitchen. He spotted the gridded pattern on the waffle iron and thought that by turning the pattern upside down, he could create a shoe without spikes. He grabbed the waffle iron, took it to his garage, and began to create molds. What came out of these experiments was the Nike Waffle Trainer, a revolutionary shoe with rubber traction that provided better grip and adapted to the running surface. The original waffle iron from Bowerman’s kitchen now sits in a display case at Nike’s headquarters.

As these examples show, a revolution in one industry can begin with an idea from another. In most cases, the fit won’t be perfect. But the mere act of comparing and combining will spark new lines of thinking.

We can’t combine ideas if we don’t see the similarities between them. Biologist Thomas H. Huxley, after reading On the Origins of Species, purportedly said, “How extremely stupid [of me] not to have thought of that!” The connection between apples and oranges appears obvious—but only in hindsight. In Darwin’s time, there were many people who had studied species. There were also many people who read Malthus and Lyell, the economist and the geologist who had inspired Darwin. But it was the rare person who studied species, who read Malthus, and who read Lyell—and who could make the connections between the three fields.

As these examples show, to connect apples and oranges, you have to collect them first. The more diverse your collection, the more interesting your output becomes. Pick up a magazine or book about a subject you know nothing about. Attend a different industry’s conference. Surround yourself with people from different professions, backgrounds, and interests. Instead of talking about the weather and repeating other small-talk platitudes, ask, “What’s the most interesting thing you’re working on right now?” The next time you find yourself in a creative jam, ask, “What other industry has faced an issue like this before?” For example, Johannes Gutenberg had a printing press problem, so he looked to other industries—like winemakers and olive oil producers—who used a screw press to extract juice and oil. Gutenberg then applied the same concept to kick-start the era of mass communication in Europe.

Organizations can take a cue from Pixar, the creative studio behind numerous box-office hits, such as Toy Story and Finding Nemo. The company encourages its employees to spend up to four hours a week taking classes at Pixar University, its professional-development program. The classes include painting, sculpting, juggling, improv, and belly dancing. Although these classes don’t have a direct bearing on filmmaking, Pixar knows that creative ideas come from seemingly unlikely places. If you keep collecting apples and oranges and spending time with them, ideas for new fruits will begin arriving soon enough.

The principle of combinatory play applies not just to ideas, but to people as well. As we’ll see in the next section, when people from different disciplines are combined, the result is more than the sum of their parts.

The Myth of the Lone Genius

“These rovers are so complicated that no one understands them.”

This might strike you as an odd statement coming from Steve Squyres, the principal investigator of the 2003 Mars Exploration Rovers project. He led the team responsible for dreaming up the rovers, devising the onboard instruments, and operating them on the Martian surface. But even to Squyres, the rovers are “too complicated for a single person to wrap their head around completely.” The understanding comes not individually, but as part of the collective brain.

We often fetishize the lone genius toiling away in the garage—whether it’s Bowerman tinkering with his waffle iron in his own garage or Jobs building the first Apple computer from the garage of his family home. It makes for a great story, but, like most stories, it’s a misleading depiction of how things work.

Optimal creativity doesn’t happen in complete isolation. Breakthroughs almost always involve a collaborative component. “If I have seen further,” Newton famously said, “it is by standing upon the shoulders of giants.” These giants come to the table with diverse perspectives, bringing their own apples and oranges for the collective body to compare and connect.

Entrepreneur and writer Frans Johansson calls this phenomenon the Medici effect. It refers to the fifteenth-century creative explosion that occurred when the wealthy Medici family brought together in Florence many accomplished individuals from different walks of life—scientists, poets, sculptors, philosophers, and more. As these individuals connected, new ideas blossomed, paving the way for the Renaissance (the word means “rebirth” in French).

A mission to Mars produces its own Medici effect by bringing together scientists and engineers to collaborate on the mission. Although these two groups tend to be lumped together in popular accounts of space exploration, they belong to very different tribes. Scientists are the idealistic truth seekers trying to understand how the universe works. The engineers, on the other hand, are more pragmatic. They must design hardware capable of implementing the scientists’ vision, while grappling with practical realities like finite budgets and schedules.

Opposites don’t always attract. On each mission, there’s a tension between “the idealistic, impractical scientists” and “the stubborn, practical engineers,” as Squyres writes. On the good missions, this tension turns into a creative dance that brings out the best in both disciplines. But on the bad missions, “it’s an acid that eats away at the collaboration until it’s rotten.”

The key to making the relationship work is combinatory play. The scientists learn some engineering, and the engineers learn some science. This approach was a top priority for Squyres. “If you came in,” he explains, “and you sat in on one of our daily tactical planning sessions where we have a team of a dozen scientists and a dozen engineers sitting together in a room, you could sit there for an hour and still not quite figure out who were the scientists and who were the engineers.” The team was blended so well—with the scientists and the engineers well versed in each other’s language and objectives—that you could hardly tell the difference.

You might assume that today’s work environment is an ideal setting for this type of blending. Sitting in cubicles in open offices, and connected through always-on technologies like email and Slack, most modern workers are constantly collaborating with each other. Maybe it’s time for a new renaissance of a modern sort that will be dubbed the Slack effect.

But not so fast. Consider the result of one study, where researchers separated the participants into three groups and asked them to solve a complex problem. The first group worked in complete isolation, the second group was in constant interaction, and the third group alternated between interaction and isolation.

The best-performing group was the third. “Intermittent breaks in interaction improve collective intelligence,” the researchers observed. Cycling between isolation and interaction improved the average score of the group while also leading the group to find the best solutions more frequently. Importantly, both low performers and high performers in the group benefited from intermittent interaction. These results suggest that learning flowed in both directions, with one person’s conclusions becoming input for the others.

Most modern work environments resemble the second, constant-interaction group, an arrangement suboptimal for creativity. As the research shows, connection is important, but so is time for isolated reflection. The process of creation can be embarrassing. “For every new good idea you have,” Asimov writes, “there are a hundred, ten thousand foolish ones, which you naturally do not care to display.” People should be able to cultivate insights on their own, come together to exchange those insights with the group, and then return to working alone, cycling between solitude and collaboration. The pattern is similar to the focus and boredom cycle that we explored earlier.

When it comes to boosting creativity, cognitive diversity—blending together your version of scientists and engineers—isn’t just a buzzword. It’s a necessity. But there’s another level of cognitive diversity that often gets overlooked.

Beginner’s Mind

In the 1860s, the silk industry in France was endangered by a disease that threatened silkworms. Chemist Jean-Baptiste Dumas urged his former student, Louis Pasteur, to work on the problem. Pasteur was hesitant. “But I never worked with silkworms,” he protested. Dumas replied, “So much the better.”

Most of us don’t do what Dumas did. We instinctively dismiss the opinions of amateurs like Pasteur. They don’t know what they’re talking about. They haven’t attended the relevant meetings. They don’t have the necessary background. They’re out of their element.

Yet it’s precisely for these reasons that outsider opinions hold value.

First-principles thinking, as Dumas’s answer implies, often has an inverse relationship to expertise. Unlike the insiders, whose identity or salary can depend on the existing state of affairs, outsiders have no stake in the status quo. Conventional wisdom is easier to tune out when you’re not smothered by it.

Consider, for example, the geological theory of continental drift, which says that continents were one big mass and drifted apart over time. The theory is the brainchild of Alfred Wegener—a meteorologist and an outsider to geology. Continental drift was initially declared absurd by geological experts who assumed that continents were stable and didn’t move. Geologist R. Thomas Chamberlain summed up the collective sentiments of the insiders: “If we are to believe in Wegener’s hypothesis we must forget everything which has been learned in the past 70 years and start all over again.” Wegener’s theory would upend the foundations of the insiders’ reputation in the field, so they stuck to their guns. For similar reasons, when Johannes Kepler discovered that planets had elliptical—rather than circular—orbits, Galileo balked. As astrophysicist Mario Livio observes, “Galileo was still prisoner to the aesthetic ideals of antiquity, which assumed that the orbits had to be perfectly symmetrical.”

Einstein’s secret to success was escaping the intellectual prison that confined other physicists. When he published his paper on special relativity, he was an unknown clerk in a Swiss patent office. As an outsider to the physics establishment, he was able to move beyond the collective body of knowledge—which, in his case, was a Newtonian perspective that treated time and space as absolute. His revolutionary paper on special relativity, “On the Electrodynamics of Moving Bodies,” looks nothing like a typical physics paper. It cites the names of only a handful of scientists and contains virtually no citations to existing works—a highly unconventional move by academic standards. In Einstein’s case, creating a revolution meant searching beyond incremental improvement, untethered by citations to works past.

Other examples abound. Musk was a latecomer to rocket science, which he picked up by reading textbooks. Bezos came to retail from the finance world, and Hastings was a software developer before he cofounded Netflix. Standing outside the establishment, these gate-crashers were in a better position to see its flaws and recognize its outdated methods.

In Zen Buddhism, this principle is known as shoshin, or beginner’s mind. As the Zen teacher Shunryu Suzuki writes, “In the beginner’s mind there are many possibilities; in the expert’s mind there are few.” This is why Wieden+Kennedy, the advertising firm responsible for many of Nike’s blockbuster ad campaigns, encourages its employees to “walk in stupid” every day and approach problems from a beginner’s viewpoint.

It was a beginner who created a billion-dollar author. When J. K. Rowling submitted a draft copy of the first Harry Potter book to publishing houses, they were unanimous in their opinion: They thought the book was not worth printing. Her manuscript was rejected by numerous publishers, until it ended up on the desk of Nigel Newton, the chairman of Bloomsbury Publishing. Newton saw potential in the book where his rivals missed it.

How? His secret was his eight-year-old bookworm daughter, Alice. After Newton handed a sample from the book to Alice, she devoured it and nagged him for more. “Dad,” she said, “this is so much better than anything else.” Alice’s input convinced her father to write a £ 2,500 check to Rowling as a meager advance for acquiring the rights to publish her book. The rest is history.

What gave Newton the multimillion-pound edge was his willingness to get the opinion of his daughter—an outsider to the publishing industry, but a member of the target audience for the book.

This isn’t to suggest that all original ideas come from beginners. To the contrary, expertise is valuable in idea generation, but experts shouldn’t work in complete isolation, the lone genius lore be damned. Experts also benefit from intermittent periods of collaboration, particularly when amateurs are brought into the mix.

IT DOESN’T TAKE a genius polymath to devise thought experiments. All it takes is a desire to collect apples and oranges, the patience to sit in boredom while your subconscious compares and connects them, and a willingness to expose the new fruits to others—whether it’s the scientists on your engineering team or your eight-year-old daughter.

Now that we’ve gotten more comfortable with thought experiments, it’s time to turn up the volume on your imagination and start reaching for the Moon.

Visit ozanvarol.com/rocket to find worksheets, challenges, and exercises to help you implement the strategies discussed in this chapter.