Though science has long told us that the brain is the most powerful organ, new evidence suggests that our minds may have reached their optimal ability. In the face of increasingly complex modern problems in education, work, and human relationships, people ought to begin “thinking outside the brain.” The Extended Mind, by acclaimed science journalist Annie Murphy Paul, posits that thinking through our bodies, environments, and communities may solve our brains’ stagnation. The scope of her research includes the voices of experts in many fields—such as economics, psychology, and biology—and reveals surprising yet ancient sources of thinking that lie beyond the confined borders of our heads.

In 1946 the Moore School of Electrical Engineering in Philadelphia revealed the first multi-purpose computer: the ENIAC. It weighed 30 tons, took over 200,000 hours to build, and was the first machine able to calculate the trajectory of gunners' artillery in a matter of seconds—a job that required three days of work by a team of people. Shortly after, newspaper and magazine articles praised the ENIAC as a "giant electronic brain" and a "brain machine." Eventually, the "cognitive revolution" of the 1950s and 1960s flipped this analogy on its head. People began comparing the brain to a computer. This comparison influenced how we think about the mind and how we study it—as an automated program that can be measured in the same way we can measure gigabytes of RAM. Under this belief, it follows that some brains, like some computers, are better than others if they possess more memory storage or processing ability. 

The brain as a computer is not the only metaphor that dominates modern perspectives on the mind. In 2002, a new hypothesis suggested that the brain also worked like a muscle and thus could be exercised. Emerging concepts such as the "growth mindset" and "grit" inspired people to take advantage of this discovery. Implementing the muscle analogy, both concepts argued that mastering new cognitive challenges improves one's mental powers. Cognitive fitness programs such as BrainHQ, Luminosity, and Cogmed commercialized and popularized the myth. Recent data has rejected the premises of these programs and revealed that they do not improve cognitive performance. Yet the cultural analogy of the brain as muscle is still widely accepted. 

Both of these analogies have limited the way “we think about thinking” by supporting our human bias toward individualism. In this view, a person's mind works as an autonomous, enclosed entity that functions without any help or connection to external sources. The mind is an independent processing machine captured in the skull and disconnected from the body and the outside world. Great people are individuals with great ideas that they created alone. This idea tempts us to think the brains are organs that we can set side by side and compare on a ladder of more or less worth among other people.

Recently, scientists have noted that our brains have reached their limits in solving the increasingly nuanced and theoretical (rather than practical) problems of modern times. IQ scores have plateaued and even dropped in countries such as Finland, Britain, Germany, and France. For a long time we assumed that if people could think through cultural problems in their minds, they could fix them. But this is no longer the case. We need to adopt an alternative to the brain analogy as a computer or muscle. Keeping our thoughts in our heads is no longer enough. We need to “offload” them outside of our brains into “embodied cognition” (bodily movements), “situated cognition” (the physical landscapes of the world), and “distributed cognition” (the community of humans around us). We must rediscover the hidden and long-ignored tradition of thinking beyond the individual brain. Though the confined modern brain is working near its maximum ability, we can breach its limits by letting our thinking depend on resources external to our brains. 

John Coates, a financial trader with a Ph.D. in economics from the University of Cambridge, was astonished to find that no matter how logical and exact he was in strategizing his trades, he lost money without exception. However, sometimes Coates sensed a gap in his conscious reasoning, a gut feeling in his body that told him what trade to make. Against all odds, he would make a profit when he obeyed this internal, physical compass instead of his education and reasoning. Coates concluded that to reason well, he had to listen to his body. 

He observed the same effect on Wall Street. To the surprise and irritation of the highly intelligent and Ivy-League educated traders, many of the people who actually made money often had no clue about how trading analytics functioned. The pattern was so persistent that Coates decided to pivot his career from finance to applied psychology. He and his colleagues performed a series of studies on traders. They found that the traders who could detect their heartbeat more accurately were the traders who made more money, regardless of their intellect or education. 

We humans absorb information from the outside world through our senses. But unbeknownst to us, our bodies also absorb tons of highly complex information that goes unnoticed. Sensors in our internal organs, muscles, and bones constantly send this information through signals to the brain. But since our conscious brain is too busy spending its energy on more concrete information such as memory and learning, the more complex information is absorbed by the realm underneath our conscious perceptions. 

Due to the complexity of these informational patterns in the world, we cannot explain their content. Still, our bodies are absorbing them. We can learn to feel and understand them by listening to our bodies via what scientists call interoception: the ability to perceive the sensations inside our body. Some people have better interoceptive awareness than others. Most do not even know that this ability exists. The good news is that practices such as meditation and body scans are proven to help people cultivate and increase their interoceptive sensibility.

Humanity’s first form of communication was gesturing. Before we could convey meaning with our words, we were fluent at conveying meaning with our bodies. Gesturing is so fundamental to human nature that it is often thought of as its own language. This physical language is so essential to communication that our species never abandoned it but we merely added a spoken one. 

Human babies encapsulate this evolutionary progress in their development. Early on, babies use their bodies to point and reach instead of saying, “pick me up.” At six months, a baby can understand and signal where her nose is before he learns to say “nose.” What’s more, children often use their hands to tell their caretakers exactly the words they want to learn. 

Adults also sometimes communicate with gestures in day-to-day activities before using speech. Research shows that our hands often grasp what to say before we can verbalize it. Professor Christian Heath has demonstrated the reality of “gestural foreshadowing” in his close analysis of patient-doctor dialogues. He recorded multiple tapes that revealed the same pattern. When we communicate, we not only gesture before we speak but also signal that we understand ideas by nodding before we hear them spoken. Scientific research reveals that our bodies “know” things before our conscious minds. For example, suppose as we are talking, we suddenly realize that we’ve said something wrong. In that case, our bodies will stop gesturing before we stop speaking. 

Other studies have shown that successful entrepreneurs are also skillful gesturers. These people are usually aware of the subconscious power of their hand motions, so much so that they rehearse them with as much rigor as they rehearse their speeches. An entrepreneur is 12 percent more likely to get funding for a project if the pitches to investors include successful gesturing.

Most of the information we absorb when we use gestures happens in our unconscious. A substantial portion of what we are listening to is gathered not from words but from motions. Unlike linear spoken language, gestures communicate holistic impressions that convey feelings, movement, and illustrations. Gestures can render abstractions with layered meanings far too complex for words to explain. In a way, gestures embody what has yet to happen. They project what is immaterial into tangible, symbolic action. Gesturing is common in the entrepreneurial world for this reason. Entrepreneurship and gesturing both operate on the boundary between what is real and what has yet to come. The language of a gesture makes us feel that we can almost understand the immaterial.

One of the reasons the brain-computer metaphor is inaccurate is that the brain works differently depending on where we are. In contrast, a laptop has a fixed structure that does not change regardless of where it is used. The environment that has most impacted the way we think is the natural landscape of our ancient home in the African savanna. Groups of wide-branched trees punctuate the ample, verdant space of the savanna. Nearby bodies of water beckon. The savanna allows us to see far in many directions and, at the same time, radiates a promise of mystery and awe. 

Studies have shown that being in nature heals us from stress and rumination and helps us improve concentration and memory. Exposure to nature can restore the nervous system after stressful situations. For people with depression, nature helps stimulate more fruitful and restorative thought patterns. One study revealed that after a walk in the park, children with ADHD could demonstrate the same concentration skills as kids without ADHD. 

The results of these studies demonstrate nature’s restorative power on the brain. Unlike our built environments that are full of sharp margins, loud noises and rigid movements, nature “employs the mind without fatigue.” The shimmering sounds and gentle movements of natural landscapes are conducive to passive attention, whereby we can effortlessly notice one thing after another without straining. Our modern battle with many psychological difficulties suggests that we need to learn to find a balance between exhausting our mental energy and replenishing it. A change of scenery can do the trick.

In 1997 an Apple commercial included a voiceover that said: “Here’s to the crazy ones … The ones who see things differently … They’re not fond of rules. And they have no respect for the status quo.” The ad’s slogan read, “Think Different.” It echoed our culture’s ideals of originality and individuality. It confirmed our assumptions that thinking the same as others or imitating others is childish or primal. Instead, we should innovate and develop new ideas on our own! Nevertheless, history and science demonstrate the contrary—imitation is neither childish nor primal, but fundamental and laborious.

Ancient Roman culture valued imitation as an art worth perfecting and made it the central value in their education system. Romans correctly estimated the rigor imitation required and the benefits it provided their youth. Early on, pupils were asked to read and examine different texts of all genres out loud, from Aesop’s fables to Cicero’s orations. Then they were asked to commit the text to memory, word for word. Once they were intimately familiar with them, the students put the text’s ideas into their own words. Eventually, they would translate the text from Greek to Latin or Latin to Greek. They would convert it from prose into verse and back. They recited them in common conversational language and in high style. Finally, the students wrote their own pieces in the same style as the author they studied. And then, they began the process all over again with a different piece. 

Research has confirmed that the Roman value of imitation is, in fact, fundamental to the evolution of human culture.

A study published in the prestigious journal Science by biology professor Kevin Laland set up a computerized battle of bots. Each bot acted according to three strategies: creating original ideas, using trial and error, and copying the other competitors. One hundred people from around the world entered the competition using one of the strategies. The results showed the bots that used the imitation strategy always won. Laland expected some of the competitors that used a hybrid system, copying in some circumstances and innovating in others, would surpass the bots that only imitated. But the winners always exclusively copied other bots.

Using simulations, historical examinations, and social analyses, researchers in many fields (from biology and economics to psychology and political science) are discovering the cultural value of imitation. They have found that acquiring new disciplines and making well-informed, smart decisions result from the arduous art of imitation. We advance culture when we accurately copy, survey, and adapt the ideas of great people before us to new contexts—not when we come up with our own.

Many of us think intelligence is innate and fixed. But staggering research reveals that intelligence results from a cohesive interaction between our minds, bodies, spaces, and relationships. Internal and external elements need to collaborate and share information to achieve the conditions conducive to great learning, memory, and problem-solving. 

These conditions can be achieved by allowing our enclosed minds to interact with “extra-neural” resources. As humans, we are well adapted to take advantage of these sources of understanding that rest outside our heads.  We have been navigating the world through our bodies, places, and social lives since the birth of our species. It wasn’t until fairly recently that we developed the ability to think theoretically and symbolically.  Of course, the ability to think abstractly has taken us to new frontiers in the development of our species. However, future advancement may require that we transfer these abstractions back into the larger world. 

Of all people, German philosopher Fredrich Nietzche advised us against coming up with ideas solely through our heads.

“Sit as little as possible;” he wrote, “do not believe any idea that was not born in the open air and of free movement — in which the muscles do not also revel.”