PDF Summary:The Great Mental Models Volume 2, by Shane Parrish and Rhiannon Beaubien

What if you could understand anything in the world by learning a finite set of rules and patterns that apply to all aspects of life? That’s the premise of The Great Mental Models series of books from Farnam Street, a website dedicated to timeless knowledge and insightful ideas.

In this second volume in the Great Mental Models series, Rhiannon Beaubien and Shane Parrish draw on models from physics, chemistry, and biology to help readers understand personal and social change as well as competitive environments such as business. They explore topics including how social change is like a chemical reaction and how the theory of relativity can help you understand somebody you disagree with.

In this guide, we organize the book’s models around the themes of movement and change, interpersonal interaction, and surviving and thriving in a competitive world. Along the way, we expand on the models by tying in related ideas and showing you how to put the book’s models into practice.

(continued)...

Beaubien and Parrish argue that in a human context, alloying describes the way people can combine their strengths to accomplish things that neither person could accomplish alone. For example, when Steve Jobs and Steve Wozniak formed Apple, they created an alloy that combined Jobs’s business and marketing instincts with Wozniak’s engineering skills to create a company and products that neither person could have created alone.

(Shortform note: Unlike physical alloys, human alloys can break apart. For instance, with the launch of the Macintosh computer—Apple’s follow-up to the successful Apple II—Jobs distanced himself from the Apple II team and Wozniak, a move that contributed to Wozniak’s decision to leave the company.)

Beaubien and Parrish point out that another benefit of working with others is that, in addition to complementing your skills, other people can supplement your knowledge and strengthen your understanding of the world. They argue that this is important in part because knowledge itself is an alloy of elements such as theoretical understanding, practical know-how, and wisdom. Often, these elements are only useful when they combine with each other. For example, it’s one thing to intellectually understand how a clutch pedal and gear stick work together to select the appropriate gear while driving—but without practice, this theoretical knowledge won’t prevent you from stalling a manual transmission car.

(Shortform note: The idea that knowledge can be strengthened by learning from others lines up with other explanations of knowledge in the Great Mental Models series. For example, in Volume 1, the authors recommend that you recognize your strengths and weaknesses and seek help from experts when you’re outside your own circle of mastery. Likewise, in Volume 3, the authors argue that knowledge compounds over time such that each bit of learning eventually adds up to exponentially greater capabilities as your knowledge and skills alloy with one another.)

Cooperation

Whereas alloying shows the power of uniting toward a common goal, the model of cooperation shows how two parties can utilize reciprocity by aligning their actions to benefit each other—even as they pursue individual interests. Beaubien and Parrish illustrate this principle with the biological phenomenon of symbiosis, which shows how cooperation lets individuals align their purposes for mutual gain.

In biology, symbiosis refers to a mutually beneficial relationship between two different species that live in close proximity. For example, clownfish spend much of their lives among the venomous tentacles of the sea anemone. The clownfish are covered in mucus that protects them from the anemone’s sting, meaning that the anemone provides them a safe home. In return, the brightly-colored clownfish attract other species that the anemone then kills and eats—leaving behind scraps that feed the clownfish.

(Shortform note: When Beaubien and Parrish describe symbiosis as a form of cooperation, they’re referring to a specific type of symbiosis called mutualism, in which both species benefit from each other’s actions. There are three other types of symbiosis, none of which has the same cooperative dynamic. The other types are commensalism (when one species benefits and the other experiences neither benefit nor harm), parasitism (when one species benefits at the other’s expense), and competition (when species directly compete for resources).)

Beaubien and Parrish point out that similar forms of cooperation exist within the human world, often in the realm of business. For example, Etsy is a platform for creators, artisans, and small retailers to sell specialty goods. The platform is based on the idea of mutual benefit—Etsy provides the infrastructure and exposure that small sellers would struggle to get on their own, and in return, Etsy makes a profit by charging listing fees, transaction fees, and payment processing fees. This sort of business model demonstrates the power of Beaubien and Parrish’s suggestion to think about what you can offer others, not just what they can offer you—often, by helping others, you help yourself as well.

(Shortform note: The principle that helping others helps you isn’t just useful in a business context—it also underpins many religious and spiritual practices. For example, in 10% Happier, retired journalist Dan Harris shares the insight—gleaned from his interview with the Dalai Lama—that practicing compassion for others benefits you, as well. Specifically, compassion makes you calmer and happier, and it helps you befriend others—which in turn increases your opportunities for the more material forms of cooperation Beaubien and Parrish describe above.)

Understanding Others

When working with others—either by alloying or cooperating—it helps to understand their perspective so that we can learn from each other, coordinate our efforts, and avoid disagreements. This section introduces two models that can help achieve these ends. First, the model of relativity points to the importance of recognizing other peoples’ points of view. Then once you know where the other party is coming from, the model of leverage suggests ways you can use the other party’s needs to get what you want.

Relativity

To work with other people effectively, you should keep in mind that everyone sees the world differently. That’s the basis of Beaubien and Parrish’s model of relativity—the idea that our understanding of a situation depends on our perspective. They explain that in physics, Einstein’s theories of relativity established that there’s no fixed frame of reference when observing physical phenomena—our perception of movement, distance, and time itself are dependent on our own position and speed relative to the event we’re observing.

An Alternative Example of Relative Perspective

While Beaubien and Parrish are correct that Einstein’s theories imply that our observations are relative, the actual theory of relativity is hard to picture in everyday life. Another scientific concept that points out the importance of perspective, and is simpler to illustrate, is the Doppler effect. The Doppler effect describes the way sound, light, and other waves distort as their source moves toward or away from the observer. This means that, in effect, two different observers will see or hear the same event differently depending on their position and movement.

For example, if you stand by the side of the road while a car drives past, you’ll notice that the car’s sound changes in pitch as it passes you—the pitch is higher as the car approaches and lower as it drives away. That’s because as the car approaches, its movement toward you makes the sound waves reach you faster (effectively increasing their frequency, which raises their pitch), and as it drives away, its increasing distance causes the sound waves to spread out (decreasing their frequency and lowering their pitch).

The key idea is that the Doppler effect only happens when the wave source and the observer are moving relative to each other. If you were moving at the same speed as the car, and alongside it, you wouldn’t notice any difference in pitch, because the sound waves would travel to you without being distorted by relative movement. On the other hand, if you were driving in the opposing lane, the effect would be amplified (which is why oncoming traffic “zips” by when you’re driving on the highway).

As a scientific principle, relativity is mostly concerned with extreme values—movement approaching the speed of light or masses great enough to significantly affect gravity. But as Beaubien and Parrish point out, relativity reminds us that no one’s account of the world is objectively true—everything we know or think we know is colored by subjective factors such as bias, limited perspective, and faulty memory. The authors explain that this is why eyewitness testimony, for example, is so unreliable. No matter how carefully witnesses observe an event or recall and describe their observations, there’s always a layer of subjective inaccuracy built into human experience.

Our Interpretations Are Noisy

The subjectivity of our interpretations is even more complicated than it first appears. In Noise, Daniel Kahneman, Olivier Sibony, and Cass R. Sunstein point out that our interpretations are affected by our experiences, personalities, and even by seemingly random factors like the weather or the time of day. In other words, your opinions aren’t just relative to other people’s—they’re relative from one moment to the next.

Furthermore, the authors argue that in social situations, our interpretations sway each other without our even noticing. For example, once one person shares an opinion, other people are more likely to support that opinion regardless of their own initial thoughts on the issue. This phenomenon is called an information cascade, and it implies that the more popular an action or opinion appears to be, the more likely you are to support it. In these cases, your interpretations aren’t solely your own—they’re relative to your social environment.

Because subjectivity is unavoidable, Beaubien and Parrish argue that it’s important to accept and appreciate other people’s points of view. They suggest that the best way to get a more complete picture of the world is to combine as many viewpoints as possible. On a practical level, that means that if you disagree with someone, don’t assume the other person is wrong—try to figure out why he or she sees things that way. Doing so can expand your horizons, improve your relationship with the other person, and cause the other person to reciprocate by taking your perspective into account.

(Shortform note: Often, the best way to learn about someone’s perspective is by having a conversation—but that’s not always easy to do when you disagree. In Difficult Conversations, Douglas Stone, Bruce Patton, and Sheila Heen offer extensive advice for listening to another person in order to understand where they’re coming from. For example, they suggest asking genuine questions with the goal of learning, paraphrasing the other person’s viewpoint to check your comprehension, and acknowledging the other person’s feelings.)

Leverage

Whereas relativity helps us understand where other people are coming from, Beaubien and Parrish point out that once you know what other people want and need, you can use the model of leverage to help you get what you want.

(Shortform note: Although Beaubien and Parrish introduce relativity and leverage as two separate concepts, they build on each other because, as we’ll see, recognizing when you have leverage and making the most of it depends on your ability to see a situation from another party’s perspective and assess how they might be thinking or feeling.)

In physics, leverage refers to the use of a lever, a simple machine consisting of a rod or plank rotating around a fixed point. Levers multiply the force you apply to them, allowing you to lift or move things you couldn’t lift on your own. For example, a child would probably have a hard time lifting another child of similar size into the air—but if the children are both seated on a teeter-totter (a type of lever), they can lift each other up with very little effort.

In a social situation, having leverage means having a way to get what you want without applying large amounts of force. Beaubien and Parrish explain that leverage results from having something that other people want or need. The more they need it—and the less you need from them—the more leverage you have. For example, if you’re the general manager of a baseball team and you’re looking to trade your left fielder, you’ll probably get a better return from a team that has a weak outfield and is struggling to make the playoffs than from a first-place team with a strong outfield.

In short, Beaubien and Parrish say, leverage isn’t about pushing other people around—it’s about understanding where they’re coming from and figuring out how to make your offer as attractive to them as possible. The authors argue that people often think of leverage as a way of manipulating or coercing others to do your bidding. They counter that leverage, at its most effective, is an extension of reciprocity. In other words, you’ll get the best returns in an exchange when you focus on what you can offer others—just as you’d do when alloying or cooperating.

Conversely, Beaubien and Parrish acknowledge that it’s possible to use leverage to exploit others—though they warn that doing so ultimately undermines your position by teaching others not to trust you. Therefore, they suggest that if you want to keep your leverage, you should not push it too far.

The Darker Side of Leverage and Empathy

Whereas Beaubien and Parrish advise combining leverage with empathy to gently push others toward your desired end, some negotiation experts take a different approach, arguing instead that you should use empathy to maximize your leverage without necessarily increasing your material offer to the other person. For example, according to former FBI hostage negotiator Chris Voss, a skilled negotiator can increase her leverage by meeting her counterpart’s emotional needs. In Never Split the Difference, Voss argues that successful negotiation depends on your ability to gain your counterpart’s trust, which you can do by making the other person feel safe and in control.

To make the other person feel safe, Voss recommends the same active listening techniques you’d use if your goal was to understand the other person’s viewpoint—the main difference is that in this case, you’re doing things like repeating the other party’s words and validating their emotions not only to understand their position but also to show that you understand it in order to get what you want from them. Voss explains that if the other party feels heard, they’re more likely to trust you.

Similarly, Voss recommends that you give the other party the illusion of control by asking open-ended questions that ultimately guide your counterpart to think about how to solve your problems. For example, if you’re selling business accounting software, you might ask a potential client, “How can I make your accounting tasks easier?” The question invites information that will help you shape your sales pitch (for example, by telling you which software features to highlight) while making the client feel like you’re on her side.

If you use these techniques to meet the other party’s emotional needs, Voss says that you’ll learn more about their hidden wants, which often include irrational biases that you can exploit in order to gain even more leverage. For instance, if the software client reveals that she thinks her current software solution is unfairly priced, the salesperson can exploit her desire for fairness to make his product look more attractive.

Part 3: Surviving and Thriving

Drawing mostly from biology and the theory of evolution, we’ll finish by exploring some of the models that, according to the authors, suggest ideas about how to survive and get ahead in a competitive world. These ideas are particularly relevant in the business world, but many of the lessons also apply more broadly to life as a whole.

Competition

First, let’s look at two models that suggest ways to survive—and perhaps triumph—in a competitive environment. Both models are drawn from the larger mental model of evolution—the theory that species undergo gradual genetic change over time due to random mutations which are filtered through natural selection. These mechanisms ensure that beneficial changes persist, while disadvantageous changes die out. Beaubien and Parrish introduce two evolutionary models—the Red Queen effect and adaptation—to explain the importance of keeping up with our competition and the mechanisms by which we can do so.

The Red Queen Effect

According to Beaubien and Parrish, one model of evolution that can help us understand social competition is the Red Queen effect, which states that evolution is an ongoing process and species must constantly adapt to competitive pressures or else be killed off. The effect is named for the Red Queen in Lewis Carroll’s Through the Looking-Glass, who tells Alice that in Wonderland, one must run as fast as possible just to stay in place.

The authors point out that similarly, if an idea or technology can’t keep up with changing needs, it’ll die off in favor of more useful or flexible alternatives. For example, Roman numerals worked fine for recording quantities and dates, but they were difficult to work with and prevented the development of more advanced mathematics like algebra and geometry. So when 12th-century Mediterranean traders encountered the 0-9 numeral system that was common in the Indian and Arab worlds, they gradually adopted that system instead—and we still use it today.

Beaubien and Parrish suggest that the Red Queen effect is particularly useful when considering business strategy, where this concept warns that just because a product or business model has been successful for a long time doesn’t mean it will continue to thrive. For example, Kodak dominated the consumer photography market for decades, and in 1975, Kodak engineers pioneered the handheld digital camera—but the company refused to market the invention because they didn’t want to disrupt their profitable film-based business model. By the 2000s, digital cameras were widespread, and Kodak filed for bankruptcy in 2012.

Traps That Kill Companies

One implication of the Red Queen effect is that innovation doesn’t help you survive unless it leads to a useful adaptation. In fact, it’s surprisingly common for companies to innovate without adapting in a meaningful way. In Loonshots, Safi Bahcall explains that this happens when companies fall into one of three traps:

The blindspot trap: When a company focuses solely on technological innovation, it can fall prey to competitors with inferior technology but superior strategy. Bahcall gives the example of Pan American Airways, which prioritized having the most advanced and luxurious fleet but went out of business after airline deregulation allowed competitors to offer lower prices and operate more efficiently.

The Moses trap: When a company has a strong leader who dictates a specific vision, the company can get fixated on a specific technology and ignore the technical innovations that ultimately let their competitors overtake them. This was the case with Kodak.

The PARC trap: If a company comes up with new ideas but never turns them into products, those ideas won’t do the company much good. This trap is named after Xerox’s Palo Alto Research Center, which in the 1970s developed crucial computing innovations such as the personal computer and the graphical user interface. Xerox never developed or marketed these ideas, and eventually, companies like Apple and Microsoft used them as an influence for their own products.

Adaptation and Exaptation

Although the Red Queen effect suggests the importance of constantly evolving, it doesn’t actually explain how to do it. Luckily, Beaubien and Parrish introduce the ideas of adaptation and exaptation to explain how you can keep up in a competitive environment.

In evolutionary biology, an adaptation is a new structure that arises to serve a specific function. For example, the reptilian species that pre-dated modern mammals had two bones—the quadrate and the articular—that formed the jaw joint. These bones were adaptations because they evolved for the specific purpose of hinging the jaw.

In a technological context, adaptation is a straightforward idea—it means coming up with new products and strategies to bring in money. The trick, as we saw with the Red Queen effect, is to keep innovating to stay ahead of your competitors.

(Shortform note: In other words, business is what Simon Sinek calls an infinite game—that is, a game that never ends and whose purpose isn’t to win, but to keep playing as long as possible. In The Infinite Game, Sinek argues that one of the keys to surviving such a game is to evolve proactively. He says that even when things are going well, you should anticipate future changes and be prepared to fundamentally transform your products and/or strategy before you’re forced to do so. By doing so, you don’t just survive change—you also benefit from it.)

Whereas biological adaptation requires developing a new structure for a specific purpose, an exaptation is the use of an existing structure for a new purpose. For example, for unknown reasons, the line of animals that eventually became mammals developed a new jaw hinge based on the squamosal and dentary bones, and shortly thereafter, the quadrate and articular bones (the old jaw hinge) re-evolved into the “hammer” and “anvil” bones of the mammalian middle ear. The middle ear bones were an exaptation because they repurposed an existing structure for a new use.

Beaubien and Parrish argue that in the human world, exaptation suggests that instead of inventing new technologies, you can be equally successful by finding new uses for existing ones. For example, the cavity magnetron is a component originally designed for radar systems in World War II. In 1946, while testing a magnetron, an engineer noticed that the snack bar in his pocket had melted—an accident that led to the repurposing of the magnetron as the basis of the microwave oven.

(Shortform note: When we think about innovation, we often think about new technologies, or in the example of the microwave, new uses for existing technologies. But as Safi Bahcall points out in Loonshots, innovation can be purely strategic, as well. For example, Ford’s assembly-line production of the Model-T was an exaptation based not on technical advances (the car and the assembly line already existed), but on a new method of assembling automobiles.)

Finally, Beaubien and Parrish point out that exaptation also means that you can create new technologies without necessarily knowing what they’ll be used for. For example, in 1968, a scientist at 3M was trying to create a strong adhesive, but instead discovered an adhesive that was weak but removable and reusable. The scientist spent years looking for a use for his creation before a colleague realized it could be used to gently hold bookmarks in place—and with that, the Post-it Note was born.

(Shortform note: In Antifragile, Nassim Nicholas Taleb points out that many of the world’s great inventions have come from this sort of directionless innovation, which he calls tinkering. Taleb argues that tinkering is more valuable than research in the traditional sense because tinkering remains open to unexpected outcomes, whereas officially funded research usually has a specific end goal in mind, which limits creativity and discourages serendipitous discoveries.)

Finding Your Way

While models like evolution and adaptation suggest ways to outcompete your rivals at the same “game,” Beaubien and Parrish offer a final set of models that instead raise the possibility of thriving through divergence—finding your own unique place in the world and choosing the best path to get you there.

Niches

Beaubien and Parrish argue that if you want to thrive, you should find your niche—a specific role in the social environment that lets you capitalize on your strengths and maximize your chances of success. The authors argue that to find the right niche, you should decide whether to be a generalist or a specialist. In biology, a niche refers to the function a species fulfills within its ecosystem. In this context, a generalist (like a raccoon) is a species that lives in a range of conditions and eats a variety of foods, whereas a specialist (like a koala) requires a specific habitat or food source.

The authors suggest that this model applies equally well to human competition, such as in the business world. In this context, a generalist business offers a wide range of products or services. Generalist businesses face fierce competition from other generalists in the same niche, but they’re also unlikely to go out of business as cultures and economies change. For example, big-box general merchandise stores like Walmart and Target are generalists because they offer one-stop shopping for groceries, home goods, clothing, electronics, and more.

By contrast, a specialist business focuses on developing a narrow niche that no one else can fill. Specialist businesses can dominate their small market niches, but they’re vulnerable to technological and cultural changes that alter that niche. For example, since 1950, the Nielsen Corporation has measured the viewership of US television programs and provided this data to networks and marketers. Thanks in part to its aggressive patenting of its technology, Nielsen historically faced no real competition. However, with the advent of streaming services, DVRs, and other technologies that have changed how people watch content, Nielsen’s accuracy has come into question and new competitors have begun to threaten Nielsen’s business model.

(Shortform note: Specialist niches might be especially valuable for companies who aren’t equipped for heavy competition. In Blue Ocean Strategy, W. Chan Kim and Renée Mauborgne describe competitive generalist markets as red oceans—that is, oceans that have been stained by blood from constant fighting. Kim and Mauborgne recommend that instead of jumping into a red ocean and trying to outcompete established businesses, you should seek a blue ocean, meaning a market where you’ll face little to no competition. They say you can do this by offering a uniquely valuable product or service—in other words, by finding or creating a specialist niche for yourself.)

In short, Beaubien and Parrish point out that generalizing and specializing both have their strengths and weaknesses—rather than promoting one over the other, they suggest learning which one best suits you so that you can strategize appropriately.

(Shortform note: Most of Beaubien and Parrish’s examples of niches relate to either technological evolution or business competition. But niches—and the question of generalization versus specialization—come up in a variety of everyday contexts, as well. For example, you could choose to pursue a wide range of hobbies (a generalist approach), or pick one or two and build your expertise in them (a specialist approach). Similarly, you could choose to read a variety of books or dive deep into a single favorite genre. The stakes of these decisions might not be as high as they are when choosing a business strategy, but the tradeoffs are similar—you always have to balance generalist breadth versus specialist depth.)

Velocity

Once you know where you want to be (for example, which niche you want to fill), you still have to figure out how to get there. That’s why Beaubien and Parrish offer the model of velocity—which suggests the importance of knowing where you’re going and not just how quickly you’re moving.

The authors explain that although we often use the words “speed” and “velocity” interchangeably, in physics, the two terms have slightly different meanings. Speed is an object’s rate of movement expressed as distance divided by time (for example, miles per hour or meters per second). Velocity is an object’s rate of movement in a designated direction—for example, a car’s speed might be 80 mph, whereas its velocity is 80 mph west.

Beaubien and Parrish explain that the distinction between speed and velocity is important because, as a metaphor, velocity reminds us to choose our direction carefully to make sure we end up where we want to go. For example, cars in a NASCAR race go fast—around 200 mph on average—but they race mostly on oval-shaped circuits, meaning that all of that speed doesn’t actually get them anywhere.

Likewise, Beaubien and Parrish say, it’s entirely possible to spend all of your time and energy working hard (gaining speed) without actually moving closer to your goals. For example, if you really care about becoming a professional musician, then getting promoted to a managerial position in your office job might increase your speed without actually taking you in the direction you want. (Shortform note: In this sense, velocity is relative—for someone who cares about succeeding in business, the managerial promotion is progress whereas a record contract would be irrelevant.)

How to Chart Your Course

So how do you choose your direction and stick to it? In Start With Why, Simon Sinek recommends that you begin with the motivating purpose behind your actions. Although Sinek talks specifically about businesses, this approach is equally valuable on a personal level. When you think not just about what you do but also about why you do it, you’ll find it easier to make choices that line up with your chosen purpose. In other words, starting with why is like having a compass—your why will always let you know whether you’re pointed in the right direction.

Unfortunately, it’s not always easy to determine which actions will take you in that chosen direction. That’s why, in The One Thing, Gary Keller suggests that you take the time to determine the one action that matters most to your goals. Keller explains that once you’ve chosen your purpose, you should ask yourself what single, concrete action will do the most to bring you toward your goal while making other actions easier or unnecessary. In other words, if your why is your compass, your one thing is like a GPS—it tells you what specific step you should take right now to get where you’re going.