Introduction
In "The Great Mental Models Volume 2," Shane Parrish explores how fundamental concepts from physics, biology, and chemistry can help us understand human society and history. Just as scientific principles allowed explorers to navigate the treacherous Arctic waters, these mental models can provide valuable insights into the complexities of social life.
This book presents seven key ideas from the hard sciences and demonstrates how they can be applied to various aspects of human behavior, historical events, and social phenomena. By examining these models, readers can gain a fresh perspective on topics ranging from the French Revolution to modern warfare and the evolution of languages.
Mass Matters in Social Change
One of the first mental models Parrish introduces is the concept of mass and its impact on social change. To illustrate this idea, he compares the contrasting fates of two substances: absinthe and lead.
In the early 20th century, absinthe became the target of a sensational campaign that led to its ban in several countries. Despite the lack of scientific evidence supporting claims of its extreme dangers, absinthe was quickly outlawed. On the other hand, lead, a genuinely toxic substance with well-documented health risks, continued to be used in various products for decades.
The difference in these outcomes can be explained by the concept of "societal mass." Like physical objects, ideas and practices in society have a kind of inertia. The larger their "mass," the more difficult they are to change or stop.
Absinthe, being a relatively new and niche product, had little societal mass. It was easy to ban because it didn't require significant changes to society's structure or habits. Lead, however, had been used for millennia in countless applications. Removing it from society would require massive changes in industries ranging from construction to automotive. Its large societal mass made it much more resistant to change.
This mental model helps us understand why some social changes happen quickly while others take much longer, even when the evidence supporting change is clear. It reminds us that when pushing for social change, we must consider not just the merits of our arguments but also the societal mass of the practices we're trying to alter.
Natural Selection in Culture
The next mental model Parrish explores is natural selection, a concept from biology that can be applied to cultural phenomena. Just as useful traits in animals tend to be passed down through generations, beneficial cultural elements tend to survive and spread.
Parrish uses the example of language evolution to illustrate this point. Latin, once the dominant language of the Roman Empire, eventually gave way to various Romance languages like Portuguese, Spanish, and Italian. This shift can be understood through the lens of natural selection.
During the Roman Empire, Latin was highly useful. It was necessary for communication within the vast empire, from military commands to trade negotiations. However, after the empire's collapse, the utility of Latin diminished. In the absence of a central authority requiring its use, Latin retreated to specific niches like religious ceremonies and scholarly work.
Meanwhile, the offshoots of Latin – the Romance languages – began to thrive. These languages incorporated much of Latin vocabulary but had simpler grammars, making them easier to learn and use. In the post-Roman world, these more accessible languages proved more useful and thus "survived" while classical Latin declined.
This mental model reminds us that cultural elements, like biological traits, tend to persist when they're useful and adapt or die out when they're not. It can help us understand why some traditions, practices, or ideas endure while others fade away.
The Importance of Early Adaptation
Parrish next introduces the concept of early adaptation, drawing parallels between biological evolution and human history. He uses the example of the peppered moth during the Industrial Revolution to illustrate this principle.
Before industrialization, light-colored peppered moths were well-camouflaged against lichen-covered tree trunks. However, as factories began producing soot that darkened tree bark, these moths became easy targets for predators. Meanwhile, a rare variety of black peppered moths suddenly found themselves with a significant survival advantage in this new environment.
Parrish applies this concept to military history, comparing France's military strategy before World War II to the light-colored moths, and Germany's strategy to the black moths. France, expecting a repeat of World War I's trench warfare, invested heavily in static defenses like the Maginot Line. Germany, on the other hand, adapted to the potential for a new kind of warfare, developing tactics based on speed and mobility.
When World War II broke out, France's failure to adapt to the changed environment led to its swift defeat, while Germany's early adaptation gave it a significant initial advantage.
This mental model underscores the importance of anticipating and adapting to changes in one's environment, whether in nature, business, or geopolitics. It suggests that success often comes not to the strongest or most established, but to those who can most quickly adapt to new conditions.
Catalysts in Chemical and Social Change
The next mental model Parrish explores is the concept of catalysts. In chemistry, a catalyst is a substance that accelerates a reaction without being consumed in the process. Parrish extends this idea to social and historical changes.
He uses the example of the Black Death in 14th century Europe to illustrate this concept. The plague, while devastating, acted as a catalyst for significant social and economic changes. The drastic reduction in population led to increased wages and lower rents, putting more money in the hands of common people. This, in turn, drove demand for new goods and spurred innovation, setting the stage for the Renaissance.
Parrish is careful to note that the Black Death didn't directly cause the Renaissance, but it accelerated changes that were already underway. This is precisely how catalysts work – they don't create new reactions, but they speed up existing ones.
Another example Parrish provides is the printing press. By making it easier and cheaper to disseminate knowledge, the printing press acted as a catalyst for the spread of ideas, accelerating the intellectual and cultural changes of the Renaissance.
This mental model helps us understand how certain events or innovations can dramatically speed up historical processes without necessarily being their root cause. It encourages us to look for catalysts in current events and to consider how they might be accelerating changes in our own time.
Knowledge as an Alloy
Parrish next introduces the concept of knowledge as an alloy, drawing parallels between the combination of metals to create stronger materials and the combination of different types of knowledge to create more powerful understanding.
He uses the example of Leonardo da Vinci, whose insatiable curiosity led him to seek out knowledge from a wide variety of sources and disciplines. Da Vinci understood that combining different types of knowledge could lead to insights and capabilities greater than any single area of expertise could provide.
Parrish then explains how this concept applies to everyday activities, using driving a car as an example. Safe and effective driving requires a combination of different types of knowledge:
- Episteme (theoretical knowledge): Understanding the rules of the road
- Techne (craft knowledge): Knowing how to operate the car's controls
- Nous (intuitive apprehension): Anticipating the actions of other drivers
- Phronesis (practical wisdom): Making prudent decisions based on experience
Just as combining copper and tin creates bronze, which is stronger than either metal alone, combining these different types of knowledge creates a more robust and effective understanding of how to drive.
This mental model encourages us to seek out diverse sources of knowledge and to look for ways to combine different types of understanding. It suggests that true mastery of a subject or skill often comes not from deep expertise in a single area, but from the ability to synthesize knowledge from multiple domains.
The Principle of Reciprocity
Parrish next explores the principle of reciprocity, drawing from Newton's third law of motion: for every action, there is an equal and opposite reaction. He extends this concept beyond physics to examine how it might apply to human behavior and life experiences.
To illustrate this idea, Parrish tells the story of Norman Bethune, a Canadian doctor who dedicated his life to providing medical care in war zones and advocating for universal healthcare. Despite his selfless service, Bethune didn't achieve fame or fortune in his lifetime. He died at 49 after contracting an infection while treating patients.
At first glance, Bethune's story might seem to contradict the idea of reciprocity – his good deeds weren't directly rewarded. However, Parrish suggests that we need to look deeper to understand the reciprocal effects of Bethune's actions.
He cites a study showing that volunteering is strongly associated with better mental and physical health, life satisfaction, self-esteem, and happiness. In this light, Bethune's selfless actions likely provided him with a sense of purpose, fulfillment, and inner peace that could be seen as a reciprocal "force" balancing his efforts.
This mental model reminds us that the effects of our actions aren't always immediately apparent or directly related to the action itself. It encourages us to consider the broader and less obvious impacts of our behaviors and choices.
Hierarchy and Leadership
The final mental model Parrish explores is the concept of hierarchy in nature and human societies. He begins by describing the hierarchical structure of a chicken coop, where some hens have priority access to food and peck at others, while those at the bottom of the hierarchy never peck at others.
Parrish then draws a parallel to human societies, using pre-revolutionary France as an example. The rigid hierarchy of king, clergy, aristocrats, and commoners mirrored the structure seen in the animal kingdom.
However, Parrish points out a crucial difference between animal and human hierarchies: humans have the capacity to question and change their social structures. The French Revolution demonstrated this, overthrowing the old order in favor of a system based on the idea of equal citizenship.
Yet, as Parrish notes, even after the revolution, new hierarchies emerged, with Napoleon eventually crowning himself emperor. This suggests that while humans may not be able to completely eliminate hierarchies, we do have the power to choose better leaders and create more equitable systems.
Parrish argues that the problem often lies in the type of people who seek leadership positions. Those who are most eager for power are often the least suited to wield it responsibly. He suggests that good leaders are those who can listen to and implement good ideas, regardless of where they come from in the hierarchy.
This mental model encourages us to be critical of existing power structures while also recognizing the persistent human tendency to form hierarchies. It suggests that our focus should be on creating systems that elevate the most capable and responsible leaders, rather than those who are simply the most ambitious or aggressive in pursuing power.
Applying the Mental Models
Throughout the book, Parrish emphasizes that these mental models are tools for thinking – lenses through which we can view and analyze complex situations. By applying these models to historical events, social phenomena, and personal experiences, we can gain new insights and develop a more nuanced understanding of the world around us.
For example, when examining a social or political movement, we might consider:
- Its "societal mass" – how entrenched is it in existing structures and habits?
- How it's adapting (or failing to adapt) to changing conditions
- What catalysts might be accelerating its progress or decline
- How it combines different types of knowledge or expertise
- What reciprocal effects it might be having, beyond its stated goals
- How it interacts with existing hierarchies or creates new ones
By applying multiple models to a single situation, we can develop a more comprehensive and nuanced understanding. This approach can help us avoid oversimplification and recognize the complex interplay of factors that shape our world.
The Limitations of Mental Models
While Parrish is enthusiastic about the power of these mental models, he also acknowledges their limitations. He emphasizes that these models are simplifications of reality, not perfect representations of it. They are useful tools for thinking, but they shouldn't be treated as infallible truths.
For instance, while the principle of reciprocity can provide insights into human behavior, it doesn't operate with the same predictability as Newton's third law of motion. Good deeds don't always generate equally good outcomes, at least not in ways we can easily measure or observe.
Similarly, while hierarchies seem to be a persistent feature of human societies, that doesn't mean they're inevitable or unchangeable. The mental model of hierarchy can help us understand power dynamics, but it shouldn't lead us to accept unfair or oppressive systems as natural or necessary.
Parrish encourages readers to use these models flexibly and critically. The goal is not to force every situation into these frameworks, but to use them as starting points for analysis and to challenge our existing ways of thinking.
Combining Mental Models
One of the key messages of the book is the power of combining different mental models. Just as knowledge itself can be seen as an alloy, our understanding of complex situations can be strengthened by applying multiple models.
For example, when examining the spread of a new technology, we might consider:
- Its "societal mass" – how much does it require people to change existing habits?
- How it's adapting to different environments or use cases
- What catalysts might be accelerating its adoption
- How it combines different types of knowledge or expertise
- What reciprocal effects it might be having on society or individuals
- How it interacts with or disrupts existing hierarchies
By applying multiple models, we can develop a more comprehensive understanding of the situation. This approach can help us identify potential challenges, opportunities, and unintended consequences that might not be apparent when viewing the situation through a single lens.
The Importance of Continuous Learning
Throughout the book, Parrish emphasizes the importance of continuous learning and intellectual curiosity. He presents Leonardo da Vinci as an exemplar of this approach, always seeking to expand his knowledge across diverse fields.
This emphasis on learning ties back to several of the mental models presented in the book:
Natural selection: In a rapidly changing world, continuous learning is a crucial adaptation that helps us remain relevant and effective.
Early adaptation: By constantly expanding our knowledge, we're better prepared to recognize and respond to changes in our environment.
Knowledge as an alloy: The more diverse our knowledge base, the more opportunities we have to create powerful combinations of ideas.
Reciprocity: The effort we put into learning often comes back to us in the form of new opportunities, insights, and capabilities.
Parrish encourages readers to cultivate a habit of lifelong learning, not just in their professional fields but across a wide range of disciplines. This broad-based approach to knowledge acquisition enables us to apply these mental models more effectively and to recognize patterns and connections that might not be apparent to more narrowly focused thinkers.
Practical Applications
While much of the book focuses on historical examples and abstract concepts, Parrish also provides guidance on how to apply these mental models in everyday life and decision-making.
For instance, when facing a difficult decision, we might:
- Consider the "mass" of our current approach – how much inertia are we dealing with?
- Look for ways to adapt early to changing circumstances
- Identify potential catalysts that could accelerate change
- Combine different types of knowledge to gain a more comprehensive understanding
- Consider the potential reciprocal effects of our choices
- Examine how our decision might interact with existing power structures
By systematically applying these models, we can approach problems from multiple angles, potentially uncovering insights or solutions that might not be apparent at first glance.
Parrish also suggests using these models as a framework for reading and analyzing news and current events. By considering how these principles might apply to global trends, political movements, or technological developments, we can develop a more nuanced understanding of the world around us.
The Power of Interdisciplinary Thinking
One of the overarching themes of "The Great Mental Models Volume 2" is the power of interdisciplinary thinking. By drawing models from physics, biology, and chemistry and applying them to human behavior and social phenomena, Parrish demonstrates the value of crossing traditional academic boundaries.
This approach suggests that some of the most powerful insights can come from unexpected connections between seemingly unrelated fields. It encourages readers to look beyond their areas of expertise and to seek out knowledge and ideas from diverse sources.
Moreover, this interdisciplinary approach aligns with the increasingly complex and interconnected nature of many modern challenges. Issues like climate change, global health crises, or the societal impacts of artificial intelligence can't be fully understood or addressed through the lens of a single discipline. By cultivating the habit of applying diverse mental models, we can develop the kind of flexible, multifaceted thinking needed to tackle these complex problems.
Conclusion
"The Great Mental Models Volume 2" offers a set of powerful tools for understanding the world around us. By introducing concepts from the hard sciences and demonstrating their applicability to social and historical phenomena, Shane Parrish provides readers with new ways of analyzing complex situations.
The mental models presented in the book – from the importance of mass in social change to the role of catalysts in historical events – offer fresh perspectives on familiar topics. They encourage us to look beyond surface-level explanations and to consider the underlying principles that shape our world.
Moreover, the book emphasizes the importance of combining these models, continuously expanding our knowledge, and thinking across disciplinary boundaries. In doing so, it not only provides specific analytical tools but also promotes a broader approach to learning and problem-solving.
Ultimately, "The Great Mental Models Volume 2" is not just about understanding the world better – it's about developing the mental flexibility and analytical skills needed to navigate an increasingly complex and rapidly changing environment. By mastering these models and the approach they represent, readers can enhance their decision-making abilities, deepen their understanding of social and historical processes, and develop a more nuanced view of the world around them.
As we face unprecedented global challenges and rapid technological change, the ability to think clearly and see connections across different domains of knowledge becomes increasingly valuable. The mental models presented in this book, when properly understood and applied, can serve as powerful tools for anyone seeking to make sense of our complex world and to make better decisions within it.