The Science of Laziness: Understanding System 1 vs System 2

Thinking back to my time in the military, I spent my final year as a naval officer drowning in paperwork. Creating countless training plans and reports was exhausting work, but the hardest part wasn’t the content itself—it was tailoring those reports to suit the tastes of my superiors. Trying to satisfy three different commanders above me was an incredibly frustrating task.

Through that tedious, nerve-wracking struggle, I learned a few golden rules of report writing experimentally: “Don’t use difficult words” and “Actively utilize diagrams, shapes, and tables.” While experience taught me that these rules were important, it was only later, reading Daniel Kahneman’s seminal work Thinking, Fast and Slow, that I understood the theoretical reason why.

It all comes down to how our brains process information, specifically the interplay of System 1 vs System 2.

The Emotional Animal That Thinks

Before diving into the systems, we must understand that humans feel emotions first and think second. The organ responsible for this is the brain. When making choices or decisions, the brain relies on memories based on ‘experience’ and ‘learning.’ Crucially, these memories are formed based on the emotions felt at that specific moment.

Emotion is the raw material in the process of memory formation. In other words, humans are not rational animals that happen to feel; we are emotional animals that happen to think. Every judgment a human makes contains emotion—even, scientists argue, among those with the most analytical minds, the balance of System 1 vs System 2 is always at play. And our brains make countless judgments every single day.

Even when we are lying blankly in bed or walking aimlessly, our brains are busy accepting vast amounts of information, judging it, and acting upon it. It sounds strange to hear our brains are busy when we feel like we are zoning out, but that is when the automatic parts of our minds are hardest at work.

The Automatic Slave and The Lazy Boss

Kahneman introduces two systems in the brain. Technically, these refer to different brain areas: ‘System 1’ largely involves the limbic system (governing emotions), and ‘System 2’ involves the prefrontal cortex (responsible for complex thought). However, the terms “System 1” and “System 2” are far more intuitive.

Our brain’s judgment depends entirely on how much System 2 gets involved in the work of System 1. This dynamic of System 1 vs System 2 defines our cognitive life.

• System 1 (The Automatic Slave): This system operates automatically and quickly, with little or no effort and no sense of voluntary control. It processes information momently from the surrounding environment, feels emotions based on it, and acts on automatic reflexes. It reports ready-made solutions to System 2, essentially asking, “Shall we just do this?”
• System 2 (The Lazy Boss): This system allocates attention to the effortful mental activities that demand it, including complex computations. The problem is, System 2 is inherently lazy. When System 1 presents a solution based on routine, System 2 usually just gives it a “PASS” stamp without checking.

So, how do we make this lazy boss work? The answer is to make System 2 uncomfortable.

Cognitive Ease vs. Cognitive Strain

What does “uncomfortable” mean to the brain? It means unfamiliar emotions, seeing things for the first time, difficulty, and complexity. These things create what Kahneman calls “Cognitive Strain.” This strain forces the interaction of System 1 vs System 2 to change.

When System 2 receives a report that is unfamiliar or difficult to understand at a glance, veins start popping on its metaphorical forehead. It is forced to wake up, re-read the report from the beginning, and engage in deep processing. It either tries to understand the difficult concept, gives up entirely, or attempts to substitute the difficult concept with familiar, easier ones to make a guess.

This process perfectly mirrored my interaction with superiors reviewing my reports. If a training plan was routine, the superior (acting like a lazy System 2) would just skim the formatting and typos. This is “Cognitive Ease.”

However, when planning a new type of training or one for which data was old and scarce, it induced “Cognitive Strain.” It was a headache for everyone. I had to study deeper to explain it clearly, and the superior had to expend mental energy to understand it.

Ultimately, a “well-written report” in the military context meant a report crafted so skillfully that it optimized the System 1 vs System 2 response of my superior, ensuring it didn’t trigger an overly critical state.

The Evolutionary Reason We Are Lazy

Let’s bring this back to a personal level. Our judgments change depending on whether System 2 is experiencing comfort (Cognitive Ease) or discomfort (Cognitive Strain).

Evolutionarily, the brain is designed to pursue “Cognitive Ease” as its default setting, heavily favoring System 1. The battle of System 1 vs System 2 is usually won by the former because it’s cheaper.

The brain consumes about 20% of the total energy our bodies use in a day. For a single organ to use 20% is enormous. In the environments of our ancestors, where food was scarce, increasing the body’s energy consumption was highly disadvantageous for survival. It is only natural that the brain evolved to use only its basic quota whenever possible and expend extra energy only in special circumstances.

Therefore, it is entirely natural that we prefer lying in bed, giggling mindlessly at YouTube videos, or avoiding conversations with people holding opposing political views. We are evolved to seek Cognitive Ease, letting System 1 run the show.

Conclusion: Challenging Your Inner Lazy Boss

We aren’t broken; we are evolved for a different world. The irony is that our environment has changed drastically. We now live in a unique environment where food is abundant and information is readily available to anyone with the will to find it. Energy replenishment is free, yet we are still programmed to minimize the energy expenditure of our decisions through the ingrained habits of System 1 vs System 2.

I’ve read self-help books by successful people in various fields. Their paths to success were all different, but through Kahneman’s lens, I seem to have found a commonality. Perhaps successful people are those who recognize this abundant environment and, when making choices, willingly embrace “Cognitive Strain,” forcing a debate between System 1 vs System 2 to improve the quality of their thinking.

Thinking about it this way, I realize I still have a long way to go. I need to reduce the number of times I choose to procrastinate on tasks because “I’m not ready.” It’s time to wake up my inner lazy boss and engage System 2 more often.

Further Reading for Context

• How Smartphones and SNS Reshaped Our Brains (Insights from InstaBrain)

Understanding Freedom and Resentment: 2 Key Psychological Forces Shaping Society

In our modern lives, we are often driven by complex emotions we don’t fully understand. Why do we desire certain luxury goods? Why do societies sometimes voluntarily give up their hard-won liberties to embrace authoritarian regimes?

By examining two profound philosophical concepts—Nietzsche’s “Ressentiment” and Erich Fromm’s analysis in Escape from Freedom—we can gain valuable insight into the psychology of freedom and resentment. Understanding these two forces is crucial to decoding both individual behaviors and larger societal trends.

1. The Trap of Resentment (“Ressentiment”)

The concept of Ressentiment is a sophisticated idea that encompasses our baser instincts of envy and inferiority. It is defined as a complex emotion composed of jealousy, hatred, and a sense of inferiority felt by those in a “weaker” position toward those they perceive as “stronger.”

The renowned philosopher Friedrich Nietzsche suggested that we become trapped by ressentiment in two main ways:

1. Subordination: Submitting to the standards set by the very subjects that trigger our ressentiment.
2. Value Inversion: Flipping values upside down because the source of the ressentiment is unattainable.

The Trap of Subordination: The Luxury Status Symbol

A prime example of the first type is the modern obsession with luxury vehicles. For many men, premium brands like BMW, Mercedes-Benz, or Audi serve as symbols of wealth, authority, and masculine appeal.

Automotive companies generate massive profits by leveraging the public’s ressentiment toward luxury car owners. Consequently, individuals who achieve some economic success often buy these cars specifically to resolve their own long-held ressentiment. The same dynamic applies to luxury watches, designer handbags, or prestigious real estate. We become subordinate to the very symbols we once envied.

The Defense Mechanism: The “Sour Grapes” Mentality

In the second scenario, when an individual lacks the ability to achieve the object of their ressentiment—or when it is realistically impossible—they protect their psyche by distorting or devaluing that object.

Returning to the luxury car example, a person trapped in this form of ressentiment might say:

“What’s the point of owning a BMW? The fuel economy is terrible, and maintenance costs a fortune. I’m much happier with my economical car.”

Recognizing whether we have fallen into this trap is crucial for personal growth. When submerged in ressentiment, we risk confusing “values we genuinely desire” with “values society rewards,” leading us to pursue goals that leave us feeling empty even if achieved.

2. The Burden of Freedom (Escape from Freedom)

While I am not a philosophy scholar, many are familiar with Erich Fromm’s seminal work, Escape from Freedom. Its central premise regarding the nature of “freedom” is deeply humbling and essential to understanding the dynamic of freedom and resentment.

Fromm analyzed a terrifying historical paradox: Why did European citizens, who had achieved freedom through immense sacrifice, voluntarily succumb to totalitarian ideologies like Fascism and Communism?

We often hear the adage, “Freedom comes with great responsibility.” This becomes viscerally real when you step out of highly structured environments into the open world. Suddenly, you face an endless barrage of questions about your future, career, and survival. You must find your own answers and lead yourself. The weight of constant decision-making can lead to paralyzing anxiety.

The Escape into Conformity

Fromm pointed out that the lower and middle classes were central supporters of Fascism. These citizens, having suddenly gained “freedom” from old monarchies, were adrift. They were unprepared to bear the burden of responsibility.

Faced with the crushing weight and loneliness of true self-responsibility, they chose totalitarianism. They chose a system that promised to eliminate the need for constant, agonizing choices. This historical example perfectly illustrates the tension between the desire for freedom and resentment toward the burdens it imposes.

For Fromm, true self-realization requires the courage and strength to live authentically, affirming one’s self thoroughly, and thinking and feeling independently.

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When Freedom and Resentment Collide in Society

The psychology of freedom and resentment converges powerfully in the social and political arena.

The ressentiment we feel toward those ahead of us in society can act as a binding force, maintaining the social reality. However, it more often protects the ego by inverting values—focusing on the flaws of successful people to convince ourselves we are better off not trying.

The Biological Basis of Comparison

Most humans cannot be entirely free from ressentiment. We are biologically wired to compare ourselves to others and derive satisfaction from relative superiority, a trait linked to serotonin levels and social dominance found even in chimpanzees. We feel superiority or relative deprivation based on our perceived social status compared to others.

The Historical Danger

This issue becomes critical because historical catastrophes have occurred when masses of people, unable to escape ressentiment, sought an escape from freedom.

Consider post-WWI Germany, crushed by debt and despair. In a desperate nation where economic hope was non-existent, the will to challenge oneself was scarce. Hitler redirected the cause of this suffering externally, whipping up intense ressentiment. He offered a populace terrified of their bleak freedom an easy path: choose totalitarianism and let the state take control.

History shows us that even if “freedom” is technically given, a society mired in the toxic interplay of freedom and resentment may fail to embrace that liberty constructively. Instead, it may make unwise, destructive choices—a danger that is particularly acute in democratic societies where power ultimately rests with the individual.

Further Reading for Context

• Self-Righteous Leadership : The Tragic Lesson of the Gracchus Brothers

5 Modern Physics Theories to Explain the Secrets of Our Universe

When we dive into modern physics theories, we often expect a clear-cut map of how the universe works. Recently, I’ve been revisiting the fascinating world of science through a popular book titled The World According to Physics by Jim Al-Khalili. This read was inspired by a recommendation from a well-known science YouTuber, “리뷰엉이: Owl’s Review,” who described it as a bridge between complex science and public understanding.

Expectations high, I opened the cover, hoping for a smooth journey through abstract concepts. However, my experience was a reminder that even the most “accessible” modern physics theories can be incredibly challenging for the human mind. The jump from classical mechanics to the quantum realm is not just a change in scale; it’s a fundamental shift in how we define “truth” and perceive the very fabric of existence.

1. The Challenge of Quantum Intuition

Honesty time: I found this book more taxing than Carlo Rovelli’s The Order of Time. While Rovelli offers a poetic and philosophical lens, Al-Khalili provides a denser, more rigorous overview of the field. As I mentioned in my previous post on The Subjectivity of Time, the way we perceive reality often clashes with mathematical evidence. This intellectual friction is precisely why modern physics theories demand a re-evaluation of our most basic assumptions about space, time, and causality.

Yet, I don’t regret reading it for a second. This experience reinforced a crucial lesson: to truly understand the cosmos, you must engage with multiple perspectives. Even in a field that seems as systematic and objective as physics, relying on a single source can lead to a narrow understanding of the truth.

2. Beyond a Single Perspective: Loop Quantum Gravity

When I read Rovelli, I was mesmerized by Loop Quantum Gravity (LQG). It offered a lens through which the universe seemed elegantly explained—spacetime woven from tiny “quantum grains.” I accepted it as the definitive structure of reality. It felt as if I had acquired a new, powerful pair of glasses to view the world, one that showed the universe not as a smooth continuum, but as a discrete, pixelated entity.

However, Al-Khalili’s book provided necessary context. I realized that LQG is just one of several modern physics theories attempting to unify quantum mechanics with gravity. There are others, like String Theory , that offer entirely different explanations, proposing that fundamental particles are not points but tiny vibrating strings. Understanding this doesn’t invalidate one theory; it highlights that we are still in the middle of a grand scientific debate, waiting for definitive experimental proof that currently lies beyond our technology.

3. Why Do Physicists Disagree?

It feels strange to an outsider: if all physicists have access to the same data, why do so many divergent modern physics theories exist? The answer lies in the nature of the quantum world itself. It operates outside the boundaries of human intuition. For more on how scientists collaborate and differ, you can check out my other post on The Objectivity of Science.

Physicists have robust mathematical models that predict outcomes perfectly, but interpreting what those models mean about reality is where the greatest minds still disagree. We can measure what happens, but we struggle to explain “why” it happens in a way that makes sense to our macroscopic brains. This ongoing search for a unified interpretation is a hallmark of modern physics theories.

4. The Core Paradox: The Double-Slit Experiment

The most famous example of this intuitive breakdown is the Double-Slit Experiment. It proves that electrons behave as both particles and waves. But why does the act of observation change their behavior? This fundamental question lies at the heart of quantum mechanics and drives much of the development in modern physics theories.

When unobserved, electrons act like waves, spreading out and creating an interference pattern. But the moment we use a camera to “watch” them or place a detector, they snap into behaving like solid particles, hitting the screen at a single point. This leads to two critical concepts within modern physics theories:

• Quantum Entanglement: Particles remaining connected across vast distances, where a change in one instantly affects the other. This “spooky action at a distance,” as Einstein called it, challenges our classical understanding of locality.
• Quantum Decoherence: The interaction with the environment that collapses the quantum state. This theory explains why the bizarre quantum world doesn’t manifest in our everyday macroscopic reality.

5. The Role of the Observer and Reality

In modern physics theories, the observer isn’t just a bystander; the act of measurement defines the reality we see. This profound insight forces us to reconsider the very nature of existence. Is there an objective reality independent of our observation? Or do we, through our interaction, bring a particular reality into being? This is why reading widely across different authors—from Al-Khalili to the legendary Stephen Hawking’s theories—is essential. Each author provides a different “map” for a territory that no human has truly seen with their own eyes.

We are forced to confront the idea that the universe might not be a single, objective reality waiting to be discovered, but rather a complex web of interactions where our very presence as observers matters. This realization is both humbling and exhilarating, as it places human consciousness at the very heart of physical inquiry, making the study of modern physics theories not just about understanding the universe, but understanding our place within it.

Conclusion: The Value of Reading Widely

By comparing diverse modern physics theories—from the poetic grains of Loop Quantum Gravity to the structured overview in The World According to Physics—you gain a much richer understanding of our reality. It’s not about mastering complex math, but about appreciating the immense, beautiful puzzle we are still trying to solve. Every book you read adds another piece to that puzzle, bringing us one step closer to understanding the world we inhabit. Embrace the challenge, and keep exploring!

Further Reading for Context

• The Order of Time: 3 Key Insights on Physics & Reality

Understanding the World Through Physics: Insights from ‘The Order of Time’

I come from a science background but have always possessed a liberal arts sensibility. In high school, physics was a challenge, while the intricate mechanisms of biology captivated me. More than a decade after graduation, I assumed physics would no longer hold any significant sway over my life.

This book, “The Order of Time“ by Carlo Rovelli, wasn’t recommended by anyone; the title simply caught my eye. It sat on my shelf for over a year before I finally picked it up. Although the only equation it presents is “∆S≥0” (The Second Law of Thermodynamics), grasping the concepts within “The Order of Time” was far from easy. I doubt I fully understood even half of it. Nevertheless, I struggled through it, grappling with the author’s teachings, and now wish to share the small, refreshing insights I gained about the nature of reality.

Objective Time = Subjective Time

We live within time. Our lives begin and end within its confines, and our very existence can be viewed as the flow of time itself. Time is a fair resource, available to everyone. Depending on how we spend it, we can lead lives revered by many or lives that pass as unnoticed as flowing water.

Among the tools humanity possesses today, science is considered the most objective index for observing and understanding the world. Physics, in particular, explores the laws of the “physical world.” Through the lens of “The Order of Time,” I realized that objective physical “time” and my subjective thoughts on time are not so different—reminding me of the idea that all disciplines ultimately unify.

The Arrow of Time: Understanding Entropy First

To understand the physical basis of time as explored in “The Order of Time,” we must grasp a key concept. The formula below is crucial as it is the only indicator in fundamental physics that reveals a “flow” or direction of time.

“∆S≥0”

This is known as “The Second Law of Thermodynamics.” ‘S’ stands for entropy, which measures the level of disorder. The formula means ‘change in entropy is always greater than or equal to zero.’ In simpler terms, thermal energy never spontaneously decreases; heat always moves from a hot object to a cold one.

When you pour hot water into a cold cup, heat transfers, and the cup gets hotter. Hot water has agitated molecules (high disorder), while a cold cup has relatively still molecules (order). Nature inherently moves from order to disorder. This increasing disorder is what we perceive as the flow of time, a central theme in “The Order of Time.”

The Evolution of Physics: From Newton to Einstein

To understand time, we must also look at space. The concepts have evolved significantly throughout history.

Ancient philosophers like Aristotle believed time measured change and that true empty space couldn’t exist. Later, Newton introduced the concepts of “absolute time,” which flows regardless of any objects, and “absolute space.”

Both viewed time and space as separate. Einstein revolutionized this, showing they are interwoven into “spacetime.” The physical reality of our universe is composed of fields formed by countless quanta. The most significant example affecting us is the gravitational field.

Mass creates gravity, and gravity warps spacetime. The stronger the gravity, the slower time flows. A clock on a mountain ticks slightly faster than a clock at sea level. Furthermore, time slows down for objects in motion. As “The Order of Time” emphasizes, time is not absolute; it is relative.

The Absence of a Universal “Now”

Due to these relativistic characteristics, a universal “present” or “now” does not exist in the universe.

Imagine a friend on a planet 4 light-years away. If you see them walking through a telescope, are they walking now? No, you are seeing light that left 4 years ago. There is no shared “now” across cosmic distances.

“The Order of Time” explains that reality is structured not linearly, but in cones of “past” and “future” relative to an observer. Outside these cones is the “extended present,” with which we cannot have a causal relationship in this instant. Our perception of a shared present is a localized illusion. We must shift from perceiving the world as “things” to perceiving it as a network of “events.”

Perceiving the World as “Events,” Not “Things”

Jack Ma, the founder of Alibaba, once said, “Everyone is a book.”

Reading “The Order of Time” gave this quote new meaning. A person, like a book, is a collection of traces (history) left in the world. By interacting with others, our brains—our neural wiring—grow and change.

Life is a series of interactions. We are shaped by the people we meet and the pain we endure. A person is an event, a history. Depending on the interactions (physical and social events) we have, one specific future out of many possibilities emerges.

The Quantum Nature of Time

Physics, and Rovelli’s analysis in “The Order of Time,” tells us that time itself is essentially quantum. It has granularity; it is not continuous but composed of discrete “time quanta.”

Furthermore, like electrons, time exists in a state of “quantum superposition” until it interacts with something physical. This interaction is what we call an event. A stopwatch clicking or receiving a test score are physical events that resolve the superposition of time into a specific reality.

The Brain: Evolved to Predict the Future

Why do we perceive time flow if it’s so complex? Because we evolved in an environment governed by entropy.

Our brain’s primary job is to manage the body’s “budget” for survival. To do this efficiently in a world where entropy always increases, the brain evolved to predict.

Our brain constantly uses past experiences to predict future events and adjust actions. Taking a test, dodging a flying ball—these are our brains navigating the flow of entropy by predicting outcomes. We are creatures designed to handle the uncertainty of the future.

Conclusion: Knowledge Determines the Future

The difference between dodging a ball and planning a career is just the scale of time. How our brain responds to these scales determines our future.

I believe “self-assurance” is the ability to navigate this process. It’s about shaping the future by collapsing the probabilities of time in a desired direction.

Physics, biology, philosophy—they all connect. Even with my limited understanding, I share these thoughts to emphasize the importance of reading. Integrating knowledge through reading is the tool that allows us to define our time and specify our future. The more tools you have to understand the world, the higher your chances of thriving. Carlo Rovelli’s “The Order of Time” is a challenging but powerful tool to add to your collection.

Further Reading for Context

• How Smartphones and SNS Reshaped Our Brains (Insights from InstaBrain)

How Smartphones and SNS Reshaped Our Brains (Insights from InstaBrain)

‘Dopamine: The Double-Edged Sword of Focus and Addiction’

In the opening of the book InstaBrain, the author dives into our brains and hormones. If you’ve read any psychology or neuroscience books, you’ll notice a recurring theme: the human brain. One key player is a hormone called dopamine.

Many have heard of it as the “reward hormone.” However, the book clarifies that dopamine is released in anticipation of a reward, not just after receiving it. It’s the excitement before the meal, not just the satisfaction after.

Originally, dopamine was a survival hormone, directing our attention to things that would help us survive, like new information. The problem is, in modern life, we spend hours every day glued to smartphones and SNS. In this environment, this ancient mechanism is making us increasingly miserable.

Smartphones and SNS flood us with endless information—stimulating ads, perfect influencer bodies, exotic travel photos—every few seconds. Each time, our brain releases a hit of dopamine. We fall into a swamp of constant novelty, becoming addicted to the endless feed provided by smartphones and SNS. This chronic exposure leads to stress from sleep disruption and feelings of inferiority (reduced serotonin) due to relative deprivation. Ultimately, this daily stress can manifest as depression.

‘Can We Really Multitask on Smartphones and SNS?’

The problems don’t end there. Many believe they are masters of “multitasking”—using smartphones and SNS while watching TV or working. The book, echoing concepts from The Organized Mind, bluntly calls these people liars.

What we call multitasking is actually the brain rapidly switching its focus from one task to another.

When you watch TV while scrolling through smartphones and SNS, your brain is quickly shifting attention between the two sources. This switching requires an “adaptation time” or a delay to refocus on the new object. This not only increases the brain’s energy consumption but also reduces work efficiency. While people claim their performance doesn’t suffer, experiments show that multitaskers have lower memory retention and task proficiency.

‘I’m Not Unhappy on Instagram?’

Finally, this is the issue I resonated with most regarding the usage of smartphones and SNS. We’ve heard about the negative impacts since the early days of Facebook, and now Instagram has been around for quite some time. The accumulated data is stark.

Long-term use of smartphones and SNS is linked to lower happiness and increased stress leading to depression. Yet, some claim they find satisfaction through these platforms. They exist, but they are the minority—only 7% of users. What distinguishes those who feel happy from those who feel stressed?

People who actively post about their daily lives and communicate with others on smartphones and SNS tend to feel happier. In contrast, “lurkers” who rarely post and only consume others’ content are more likely to feel inferiority and stress.

Reading this made me realize my own attitude. Before using Instagram for book promotion, I had a personal account where I didn’t communicate; I just watched others’ seemingly happy lives. Seeing their perfect lives on smartphones and SNS while mine felt stagnant was irritating (relative deprivation), so I eventually deleted the account. My experience confirms that this tendency is stronger in people who are already under stress.

‘How to Live Wisely with Smartphones and SNS’

We are told to stay away from these devices, but how can we control something so deeply embedded in our lives? Teenagers show the highest rates of depression and stress from smartphones and SNS addiction. However, reducing their average daily use from 3-4 hours to under 2 hours (a digital detox) significantly decreased stress and depression.

Furthermore, exercise is mandatory. As many psychology and brain science books emphasize, our brains are still stuck in the Stone Age. Physical activity, especially running, was essential for survival and required maximum concentration. Exercise is incredibly effective not only for focus but also for reducing stress caused by the overuse of smartphones and SNS. The author validated this by prescribing running to depression patients and seeing significant improvements.

I deeply empathize with this. Running is an indispensable stress-relief tool for humans. I once felt a complex mix of anger, sadness, and injustice after a betrayal. I couldn’t talk to anyone and felt like I would explode. So, I just ran. After running 10km, I regained my reason and calmed down. I ran every day for about two months. Perhaps running when I couldn’t bear it anymore was a natural evolutionary response to save myself.

Finishing this book, two thoughts lingered: “I must gift this book to anyone getting married or raising children,” and “I need to read more and become wiser for my own child.” No one wants to raise a child with poor impulse control due to unrestricted access to smartphones and SNS. While many parents may already realize this, I leave this book recommendation for those who might not. I’ll end with a quote from the book:

“We limit how much technology our kids use at home.” – Steve Jobs, Co-founder of Apple –

Further Reading for Context

• Early Childhood Brain Development: 7 Neuroscience Insights for Parents