The Great Mental Models: Volume 3, Systems and Mathematics – Farnam Street

The Great Mental Models: Volume 3, Systems and Mathematics – by Farnam Street
Date read: 2/11/22. Recommendation: 8/10.

I love this series. Volume One focuses on mental models from general thinking concepts. Volume Two focuses on physics, chemistry, and biology. And this volume focuses on arming you with mental models from systems thinking and mathematics. It’s a beautifully designed book, just like the others. And they do a wonderful job relating what are often dense, abstract concepts back to real-life applications. My favorite sections discussed feedback loops, margin of safety, emergence, surface area, and global + local maxima.

See my notes below or Amazon for details and reviews.

My Notes:

Systems thinking:
“Systems thinking is a discipline for seeing wholes. It is a framework for seeing interrelationships rather than things, for seeing patterns of change rather than static snapshots.” Peter Senge

Feedback loops:
“The people you spend the most time with are the ones who give you the most feedback on your behavior and thus have the most impact on the choices you make and the ways you change.” FS

Bottlenecks versus constraints:
“A bottleneck is something we can alleviate; a constraint is a fundamental limitation of the system. So a machine that keeps breaking down is a bottleneck, but the fact there are twenty-four hours in the day is a constraint.” FS

Margin of safety:
“A margin of safety is often necessary to ensure systems can handle stressors and unpredictable circumstances.” FS

Drive towards self-sufficiency: “Life will throw at you challenges that require capabilities outside of your natural strengths. The only way to be ready is to first build as cast a repertoire of knowledge as you can in anticipation of the possibilities you might face, and second to cultivate the ability to know what is relevant and useful.” FS

“Knowledge then can be conceptualized as a margin of safety, a buffer against the inevitable unexpected challenges that you will have to face.” FS

Churn:
A certain level of churn is a healthy part of systems, some degree of turnover creates stability and if it’s not occurring, it must be built in. It brings fresh ideas in, allows others to step up, and allows the system to adapt/evolve. 

Sovereign individual: “People being able to leave as they wish places checks on abuses of power. The same is true for countries or companies. People need the freedom to vote with their feet if things get too bad.” FS

Algorithms:
Algorithms turn inputs into outputs: “An algorithm is a methodical set of steps that can be used to make calculations, resolve problems, and reach decisions. An algorithm isn’t a particular calculation, but the method followed when making the calculation.” Yuval Noah Harari

Emergence:
Focus on your starting point—stack the skills that you’re naturally drawn towards—and the way that impacts your trajectory: “You don’t always need to plan things all the way to the end. If you have a simple starting point on the right trajectory, surprising things can pan out through the power of emergence.” FS

Compounding:
“Humans have evolved to be pretty good at using past experience to guide future decisions, so a lot of knowledge compounding happens naturally over time, especially when we are young. But sometimes we get stale. We stop reinvesting that interest because we stop challenging ourselves. We stop compounding our learning. Twenty years of living become the same year repeated 20 times.” FS

Randomness:
“Randomness as a model reminds us that sometimes our pattern-seeking, narrative-building tendencies can be unproductive. Using randomness as a tool can help us get a fresh perspective and lift us out of the ruts we have built.” FS

Surface area:
“Surface area is useful when considering the amount of dependencies or assumptions something has. A program whose code has little surface area is much more likely to age well and be robust than a piece with many dependencies. The same goes for projects. If a project depends on ten teams, it’s much less likely to finish on time than one with less surface area.” FS

Multidisciplinary approach increases your personal surface area, allowing you make more connections and outthink others.

Different situations require different surface areas. 

Global and local maxima:
Sigmoid curve: “Using global and local maxima as a model is about knowing when you have hit your peak, or if there is still potential to go higher. It reminds us that sometimes we have to go down to go back up.” FS

Hill climbing: Requires changing your approach, you have to take a few steps down to reach the peak of a higher hill. This requires perspective and assessing the terrain from different vantage points. This is all about playing the long game, not clinging to the comfort of your current position. 

The Great Mental Models, Volume Two – Shane Parrish

The Great Mental Models, Volume Two – by Shane Parrish (Farnam Street)
Recommendation: 9/10. Date read: 1/18/21.

The Great Mental Models series by Farnam Street blows me away. The second book in this series focuses on the hard sciences including chemistry, biology, and physics. They do a tremendous job articulating the laws and models in a way that makes sense for those without a Ph.D. And rather than simply stating the law and sticking with the abstract, they translate how it applies to situations in your everyday life. They explain how laws of reciprocity translate to relationships, the ways in which inertia requires us to overcome the allure of what’s easy, and how an ecosystem translates to the most effective, creative, and collaborative working cultures.

See my notes below or Amazon for details and reviews.

My Notes:

Relativity:
“The limits of perspective are fundamental to how the world works. Considering multiple perspectives is the best chance we have to understand what is really going on.”

“What matters is understanding the complexity and value of multiple perspectives. No one sees it all. Multiple perspectives layered together reduce blind spots and offer us a more textured and truer sense of the underlying reality.” 

Reciprocity:
Life is an iterative and compounding game…it pays to go positive and go first.

“The more people you help, the more people you will have willing to help you.”

“If you want people to be thoughtful and kind, be thoughtful and kind. If you want people to listen to you, listen to them. The best way to achieve success is to deserve success.”

Thermodynamics:
First law of thermodynamics: energy cannot be created or destroyed. It can only be transferred or changed from one form to another. Consider how this applies in death. 

“Entropy reminds us that energy is required to maintain order. You need to anticipate things falling apart and focus on prevention.”

Exposure: “Mixing cultures gives them common ground. We move toward social equilibrium when we share ideas and values that have the same foundations.”

“Art is born out of as well as encapsulates the continuing battle between order and chaos. It seeks order or form, even when portraying anarchy.” John Yorke

Storytelling: “Every act of perception is an attempt to impose order, to make sense of a chaotic universe.”

Inertia:
“We stay at jobs we hate, avoid meaningful conversations with people of different opinions, and almost never change the religion our parents imposed on us at birth. All because it is easier to stay on our current path, however stagnant and unfulfilling it might be.”

Amount of effort required to change a habit is greater proportional to the length of time we’ve had it. This applies to both good habits and bad habits. Once you’ve established decades of good habits, it compounds and becomes difficult to stop your own success. The same applies in the opposite direction. 

Velocity:
Direction > speed

“If a man does not know to what port he is steering, no wind is favorable to him.” Seneca

Alloying:
Stacking skills is a force multiplier: “Alloying is about increasing strength through the combination of elements.”

Evolution:
“On the human timescale, adaptability is about recognizing when the way you have done things in the past is becoming less and less successful in a changing environment.” 

What got you here won’t keep you here or allow you to get to the next level. Personal growth is a lifelong effort and requires taking new risks: “You can’t stop adapting, because no one around you is stopping…Staying the same as we are often means falling behind.” 

“Success is measured by persistence.” Geerat Vermeij

Experimentation for its own sake matters: “We must not forget that when radium was discovered no one knew that it would prove useful in hospitals. The work was one of pure science. And this is proof that scientific work must not be considered from the point of view of the direct usefulness of it. It must be done for itself, for the beauty of science, and then there is always the chance that a scientific discovery may become like the radium a benefit for humanity.” Marie Curie

Antifragile: “Complacency will kill you. However, it’s not strength that survives, but adaptability. Strength becomes rigidity…Real success comes from being flexible enough to change, to let go of what worked in the past, and to focus on what you need to thrive in the future.”

Ecosystem:
Culture = the key to perseverance. Bill Walsh leading the 49ers: “Walsh recognized that a football organization’s culture is ultimately the system that will determine if a team can sustain the effort needed to win a championship.” Walsh believed, “everyone has a role, and every role is essential.” But they all had to be pointing in the same direction.

“The stronger and more resilient a system, the easier it can adapt and bounce back.” For Walsh it wasn’t about superstars or certain formations, “It was about building a culture that could be flexible in effectively responding to ever-changing environmental pressure.”

Self-preservation:
“Freeze mode usually takes over when the accumulation of stressors is so great that we can no longer really function.” 

Man’s search for meaning: “For humans, survival is not merely a binary like dead/alive. We don’t want to just continue breathing, but to have a life that we perceive as having meaning, value, or at least a point.”

Replication:
Commander’s intent: “Sharing the information necessary to empower subordinate commanders on the scene.” Too rigid and the person doing the work can’t adapt and innovate to execute against the strategy when circumstances change. Encourages troops to consider the why behind an order and the underlying strategy. 

Four elements of commander’s intent: formulate, communicate, interpret, and implement. The first two are the responsibilities of the senior commander. The second two are the responsibilities of the subordinate commander. 

Commander’s must consider four criteria:

1. Explain the rationale (the why): vision + strategy

2. Establish operational limits: constraints

3. Get feedback often: listen and learn

4. Recognize individual differences: leverage individual strengths

Incentives:
“Never, ever, think about something else when you should be thinking about the power of incentives.” Charlie Munger

“An incentive is a bullet, a key: an often-tiny object with astonishing power to change a situation.” Stephen D. Levitt

Least effort principle:
“Change is costly for most organisms. It can be easier to keep doing whatever has guaranteed their survival so far than to try something new that might fail and waste energy or endanger them. The instinct to minimize energy output can lead us to be resistant to change or risk-taking. “

Default thinking tendencies (aka heuristics): “Using this model as a lens helps us better understand our default thinking tendencies, and how our patterns of movement impact our physical environments.”