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Business & Economics Decision-making & Problem Solving

The Great Mental Models, Volume 2

Physics, Chemistry, and Biology

by (author) Shane Parrish & Rhiannon Beaubien

Publisher
Penguin Publishing Group
Initial publish date
Oct 2024
Category
Decision-Making & Problem Solving, Skills, Personal & Practical Guides
  • Hardback

    ISBN
    9780593719985
    Publish Date
    Oct 2024
    List Price
    $48.00

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Description

From the New York Times bestselling author of Clear Thinking and Farnam Street founder, Shane Parrish.
The second book in the timeless Great Mental Models series.

Time and time again, great thinkers such as Charlie Munger and Warren Buffett have credited their success to mental models–representations of how something works that can scale onto other fields.

Mastering a small number of mental models enables you to rapidly grasp new information, identify patterns others miss, and avoid the common mistakes that hold people back.

Volume 2 of The Great Mental Models series provides a collection of over twenty important concepts from physics, chemistry, and biology in a clear and accessible style. Not only will you better understand the hidden forces that influence the world around you, you’ll also learn how those forces can work to your advantage.

Some of the mental models covered in this book include:

  • Leverage: When the application of a small force to one end results in a larger force at the other end.
  • Inertia: An object (or organization) at rest will stay at rest unless acted upon by an external force.
  • Activation Energy: The minimum amount of energy required to incite a chemical reaction.
  • Ecosystems: A community of organisms that have complex relationships to each other.

The Great Mental Models series demystifies once elusive concepts and illuminates rich knowledge that traditional education overlooks. This series is the most comprehensive and accessible guide on using mental models to better understand our world, solve problems, and gain an advantage.

About the authors

Shane is the founder of Farnam Street, and currently resides in Ottawa, Canada. Farnam Street (FS) is one of the world’s fastest growing websites, dedicated to helping our readers master the best of what other people have already figured out. We curate, examine and explore the timeless ideas and mental models that history’s brightest minds have used to live lives of purpose. Our readers include students, teachers, CEOs, coaches, athletes, artists, leaders, followers, politicians and more. They’re not defined by gender, age, income, or politics but rather by a shared passion for avoiding problems, making better decisions, and lifelong learning.

Shane Parrish's profile page

Rhiannon Beaubien is a writer and the managing editor at Farnam Street Media where she leads the development of The Great Mental Models book series. She is based out of Ottawa, Canada and regularly explores how to apply the timeless ideas behind mental models on fs.blog. She worked at a Canadian intelligence agency for more than ten years and is also an author of fiction.

Rhiannon Beaubien's profile page

Excerpt: The Great Mental Models, Volume 2: Physics, Chemistry, and Biology (by (author) Shane Parrish & Rhiannon Beaubien)

Relativity

Put it into perspective.

The theory of relativity is founded on empathy. Not empathy in the ordinary emotional sense; empathy in
a rigorous scientific sense. The crucial
idea is to imagine how things would appear
to someone who's moving in a different way than you are.

-Steven Strogatz

We often think someone is wrong because they see things from a different perspective than we do. Relativity helps us to understand that there is more than one way to see everything. That doesn't mean everyone's perspective is equally valid, only that we might not have the most complete view into a problem or situation.

Thought Experiments
That Changed the World

The science of relativity is best explained through two famous thought experiments-one conducted by Galileo and the other by Albert Einstein. Each describes a situation that demonstrates the reality of differing perspectives.

Thought Experiments

In volume 1, we dedicated a chapter to thought experiments because they are such valuable mental models. Frequently used as tools by scientists, thought experiments let us take on the impossible, evaluate the potential consequences of our actions, and reexamine history to make better decisions. They are rigorous applications of the scientific method to determine what we can infer from what we can imagine.

In the 1630s, Galileo discovered that any two observers moving at constant speed and direction will obtain the same results for all mechanical experiments they perform.

Galileo's original thought experiment describes a scientist on a ship moving at constant velocity. The scientist is belowdecks with no portholes to give him a frame of reference for the movement of the ship. When this scientist drops a ball from waist level, he will notice only the vertical movement caused by gravity. He will observe that the ball drops to the floor of the ship. However, there is also a horizontal movement that the scientist doesn't perceive. Both the scientist and the ball are also moving the distance covered by the ship as the ball is falling to the ground.

An outside observer, someone standing on a nearby beach or a fish in the water, can detect the complete movement of the ball because their perspective is different. By being outside the ship, they see a more complete version of reality. The scientist on the boat would have to make a conscious effort to remember that both he and the ball are moving with the ship. Before you conclude that the motion of the ship should be obvious to the scientist, consider how often you reflect on your movement through space every day. Right now, you probably feel as though you're stationary. However, if you're on Earth, you're moving around the sun at sixty-seven thousand miles per hour. Galileo developed this thought experiment partly thanks to his belief that Copernicus was right and that the Earth itself is in motion that we do not feel.

Perspective influences what we perceive as reality and how we understand the world. Galileo's thought experiment is one you can use all the time. Imagine the scientist performing experiments on the boat and ask yourself: Now what does a fish see? And how does that relate to what the scientist experiences? Imagine being either one, or a bird in the sky, and you start to get an idea of how multiple eyewitness accounts of the same robbery can be so different.

To use this yourself, imagine seeing a situation through the eyes of all the participants. Changing your perspective and looking at things through the eyes of others not only reveals blind spots but also creates empathy.

In the early 1900s, Einstein used another famous thought experiment when developing his theory of special relativity, which linked mass and energy using the formula E = mc. This formula demonstrates that energy is equivalent to mass times the speed of light squared. With this theory, Einstein stated that the speed of light is fixed within any frame of reference moving at a constant velocity, and therefore there is no fixed frame of reference from which one can measure the physical laws. This is what Galileo had argued, but his ideas were put aside in the 1700s in favor of a view that said there was an absolute frame of reference. Einstein's theory of special relativity revived Galileo's ideas.

Einstein's thought experiment to describe special relativity illustrated the concept that observers in relative motion experience time differently. This means that two events can happen simultaneously from one observer's perspective and at different times from another observer's perspective. Both are right. Here is the experiment:

Imagine you are watching a train go by. Lightning strikes each end just as the train's midpoint is passing you. The lightning strikes are each the same distance from you, so you correctly conclude that the two bolts of lightning hit the train at exactly the same time.

Later on, you catch up with your friend, who was on the train. "Crazy that two bolts of lightning struck your train at exactly the same time," you say.

"What are you talking about?" she responds. "The front of the train got hit by lightning first."

You dismiss her interpretation. After all, you witnessed the whole thing. But here is what was happening for her:

She was sitting at the midpoint of the train. If the train had been stationary, she would have observed the two lightning strikes being simultaneous like you did. However, because the train was moving, the light from the rear strike had farther to travel to reach her. She perceived the light from the strike at the front first. So, she correctly concluded that the lightning strikes were not simultaneous; the one in front happened first.

These are two valid interpretations of the same event. Both are correct. The difference arises because of the perspective of each person.

Our perspective is very much unique to us, as both Galileo and Einstein so vividly demonstrated. In the day-to-day world that we live in, this means not only that you are seeing what nobody else sees but also that you do not automatically, unconsciously see through the eyes of others. There is an objective reality, but none of us can perceive it in totality without doing a little work. Is it any wonder we make suboptimal decisions?

Perspective-Taking in Psychology

Perspective-taking in psychology refers to the ability to perceive a situation from an alternative point of view. We are not born with this ability. It develops throughout childhood. There are two broad types of perspectives that we learn: differing physical perspectives, such as that the view out your neighbor's window is different than yours; and conceptual perspectives, such as that people have different feelings or beliefs that in turn influence their perspectives. Some conditions can negatively impact the development of the ability to fully understand a different perspective. And while we are capable of appreciating the wide variety of perspectives that exist, we are often lazy about developing this ability.

The Subjectivity of Perspective

You are always going to have an imperfect perspective. You can't see everything at once. Nor will you be able to completely trust that everything you do see is viewed by others. In concrete terms, relativity highlights a subjectivity of perspective that explains partly why eyewitness testimonies have lost their credibility over the years.

When considering an eyewitness testimony during a trial, there are many aspects to consider in order to understand that person's perspective. First, there are the physical aspects: How good is that person's vision? What was the light like at the time? How long did they have to observe the person in question? But there are also a host of psychological ones: What mood was the person in? Were they rushing to get somewhere? Had they just had a fight with their spouse? Do they have an incentive to take a certain position? And what about the biases: Do they consider certain ethnicities more likely to commit crimes? How predisposed are they to being helpful with police? All of this factors into what a witness believes they saw and helps explain why two witnesses can have remarkably different accounts of the same situation, as in Rashomon.

Rashomon, the classic Japanese film, is an excellent exploration of the differences in the testimonies of several eyewitnesses to the same crime. A samurai is found murdered in a forest. A bandit is accused of the crime. During the subsequent trial, the bandit, the samurai-speaking through a medium-his wife, and a woodcutter who observed the whole incident each give testimony. Each story is different, partly due to the self-interest of each of the characters, and partly because each can understand the events that play out only through a single perspective-their own.

Rashomon is interesting because the end does not give the viewer "the truth." The audience does not get any closure on what happened, which is an accurate portrayal of life. They are simply left with the contradictory testimonies and the implication that each of these has become the truth for the person telling them.

In addition, our memories are not infallible. We often think of memories as being like a video recording, capturing a scene with perfect fidelity. The truth is far more complicated. Our memories are highly subjective and malleable. We often misattribute memories, such as a witness thinking something that they read in the news about a crime is something they witnessed. We are also highly suggestible, such as when a police officer asks us a leading question or uses emotive language.

Our memories of the past are also distorted by what we know now, such as when a witness learns a new piece of information and feels they knew it at the time. These and other common memory distortions feed into the subjectivity of eyewitness reports. People rewrite and reshape their memories, often to fit their existing beliefs. We often feel committed to our original perception and unconsciously adjust our memories to support what we think we originally saw.

When juries hear eyewitness testimony, they must sort through the limits and influences on that person's perspective and consider how self-interest and time have distorted the person's memory. It is no small feat. One example of the challenge is chronicled here.

On the morning of July 4, 2000, twenty-year-old Chris Kinison was killed in a convenience store parking lot in Ocean Shores, Washington, USA. Minh Duc Hong was charged with the crime. Hong was visiting the area to see a fireworks show with his twin, Hung Hong. Both were Asian Americans, and Kinison was white. During the subsequent trial, a dozen eyewitnesses provided testimony. As David A. Neiwert explains in Death on the Fourth of July, "For every bit of testimony, it sometimes seemed, there arose a view of events that conflicted with the description provided by previous witnesses, creating a web of questions about competing self-interests, and the extent to which they colored different witnesses' testimony." Many witnesses described seeing things they physically could not have, which was determined once their positioning during the violence was mapped out. Others were clearly biased by their relationship with the victim-a local-versus the accused, who was from out of town. Racial bias was a huge factor, and in his book, Neiwert makes the case for Minh Hong first being a victim of a hate crime, whose subsequent actions were really about defense.

According to witnesses, Kinison waved a Confederate battle flag at Hong and his friends and shouted racial slurs. He also made threatening gestures, indicating a desire to harm Hong, who took a knife from the convenience store, fearing for his safety. When Kinison physically assaulted Hong's brother, Hong used the knife on him. Kinison had previous accusations of racist violent threats.

Many of the witnesses had been drinking, and many admitted to being scared. These distortions meant that the jury did not get a reliable, consistent account from each witness. They had to piece together what might have happened. The jury then had to evaluate the credibility of how each witness saw the crime and the laws of physics governing the physical perspectives. One life had already ended. The future of another one was completely dependent on how the jury untangled the testimony through the limits of their own perceptions.

After deliberation, the jury could not reach a verdict and the judge declared a mistrial. The jury revealed that they had deadlocked 11-1 in favor of acquittal. What's interesting, though, is the ambiguous end to the story. The jurors continued to be comfortable with the position they took, believing that Minh Hong acted reasonably in self-defense. The local sheriff's office recognized that Hong had been the victim of a hate crime and the officers committed to an education program so they could deal with similar situations better in the future. But, Neiwert further writes, "If there is any lingering sentiment in Ocean Shores, it is a quiet dismay at the outcome of Minh Hong's trial. Even though the Grays Harbor jury found otherwise, many in town, especially those who knew Chris Kinison, believe an injustice was done."

The multiple and conflicting perspectives displayed in the trial of Minh Hong are a common phenomenon. We have all been in situations in which we have a totally different perspective on events than the person standing next to us. It's important to be aware of and compensate for different perspectives if you want to get the most complete picture possible of the situation you are in. What you see is never all there is.

When people thought the earth was flat, they were wrong. When people thought the earth was spherical, they were wrong. But if you think that thinking the earth is spherical is just as wrong as thinking the earth is flat, then your view is wronger than both of them put together.

-Isaac Asimov

Through the Eyes of Others

The limits of perspective are fundamental to how the world works. Considering multiple perspectives is the best chance we have to understand. Given that you can't go back in time to situate yourself differently, what can you do to augment your perspective? This is where thought experiments come in handy. Think back to Galileo's scenario of the scientist conducting experiments on the boat. The scientist cannot hang out in the ocean and watch the boat go past. Our scientist can, however, imagine what the view would be like from the perspective of a fish.

Thought experiments don't have to be confined to what already is or even what's possible. The scientist, when considering the perspective of the fish, can also imagine the boat as being made of glass and the water as easy to see through as air. Or he need not limit the experiment to the visual perspective of the fish. After all, we don't gain perspective only with our eyes, but through the lens of our experiences, biases, desires, and more. This can explain a lot of human behavior.

Editorial Reviews

“I’m really glad this exists in the world and I can see that I will be recommending it often.”
— Matt Mullenweg, co-founder of WordPress, founder and CEO of Automattic

“If you’ve read Charlie Munger’s Almanack this is the book you deeply crave in its wake. … Learn the big ideas from the big disciplines and you’ll be able to twist and turn problems in interesting ways at unprecedented speeds. … You owe yourself this book.”
— Simon Eskildsen

“This is what non-fiction books should aspire to be like. Informative, concise, universal, practical, visual, sharing stories and examples for context. Definitely, a must-read if you’re into universal multi-disciplinary thinking.”
— Carl Rannaberg

“I can truly say it is one of the best books I’ve ever had the pleasure of getting lost in. I loved the book and the challenges to conventional wisdom and thinking it presents.”
— Rod Berryman

“Want to learn? Read This! This should be a standard text for high school and university students.”
— Code Cubitt

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