12 Lessons from 55,000 pages of books

How 136 books can update our prior knowledge of the world


Reading 136 books in a year does not get you to enlightenment. It may lead in the other direction, towards greater confusion. How? In those 55,000 pages, you are bound to find inconsistencies, such as pieces of advice that directly contradict each other. You are also guaranteed to read about people who were successful using one strategy and people who were successful using the opposite approach. What you find over 136 books is not one path to success, but many, as life is so varied, there is no single master strategy.

Therefore, when I thought about what I had learned from reading 136 books in 2019, I didn’t want to highlight hundreds of paths to high achievement. Instead, I’ve framed the lessons as updates to 12 pre-existing beliefs I, or wider society, held. These updates are not corrections because knowledge continually changes, and many of our old worldviews were logical, given the information at the time.

As we gain more knowledge, we should adjust our current worldview to better align with the data. In the language of Bayesian thinking, we come into a book with existing beliefs, priors, gather additional data, and emerge with a new understanding, posterior, that is more correct (in terms of the data) than the prior. This article then is a process of Bayesian reasoning to alter our collective beliefs to match with the data from over a hundred books.

For the full ranking of the 136 books with short summaries, see this article.

Prior: Human society is zero-sum. When one person gains, another must lose.

Update: Modern civilization, especially our economy, is positive-sum; one participant’s gain should lead to benefits for another. Here’s an example for individuals: if we purchase a pair of shoes from a shopkeeper, we both come away ahead from the transaction. The shopkeeper gets what she wants, a currency of exchange she can use to buy other goods, and we have a pair of shoes, much quicker and cheaper than we could make ourselves.

On a country level, division of labor means that each country produces the goods that are most efficient for them to make. When US manufacturing moved to China, hundreds of millions of Chinese were raised out of poverty while US citizens enjoyed low prices for consumer goods. The US economy then moved to the next stage, driven primarily by services and technology, because that is what the country could do better than others. Some workers in the US lost their old manufacturing jobs, but the overall gains far outweighed any negatives.

How should this affect your life? Remember that in human interactions, both people should come out ahead. In an argument, this means being open-minded and willing to compromise. At work, this means helping your co-workers and getting help from, which will increase both parties’ well-being. When we help others, we help ourselves.

Books: The Moral Animal, The Life You Can Save, Abundance: The Future is Better Than You Think, Progress: Ten Reasons to Look Forward to the Future

Prior: The talent that people are born with determines success in life.

Update: Innate talent has a small effect on outcomes in most human endeavors. Rather than merely activating our innate abilities, we can only increase our chances of success in our pursuits (not guarantee it) through extensive practice over years or decades. Moreover, high achievement does not mean doing the right thing once or being born with specific skills, it requires repeatedly making the correct choice in small everyday decisions thousands of times for years.

Activities such as practicing coding every day, choosing to go on a run, or practicing a presentation one more time are not exciting, but they are what determines achievement in the long term. Humans can master new skills, change habits, or rise to the top of a field, but they take deliberate training and a commitment to the process.

Books: Peak: Secrets from the New Science of Expertise, Endure: Mind, Body, and the Curiously Elastic Limits of Human Performance, Grit: The Power of Passion and Perseverance, The Power of Habit: Why We Do What We Do in Life and Business

Prior: Humanity is on the decline, and the future will be worse than the present.

Update: We live in the Golden Age of civilization by every objective measure: health, wealth, peace, and knowledge, and there are no signs we are reversing. We’ve lifted more than a billion people out of extreme poverty in the past 30 years, ended natural famine, achieved unprecedented levels of peace, eradicated diseases, solved significant environmental problems like acid rain and the ozone hole, raised worldwide life expectancy to 70, vaccinated 80% of children worldwide against some disease, and slowed population growth to the point that global population will peak in the 2100s around 10.5 billion people.

The trends are pointing in the right direction because we are adding productive people, and technology allows us to multiply human productivity. More productive people are positive, and eventually, who knows what we can accomplish with 10 billion people that have unlimited access to energy and unlimited nearly-free computing power (the developed world has already reached this point). We have not run out of resources because technology allows us to find new reserves and helps us use existing resources more efficiently. We need to remember that progress is not always linearly in the right direction. Still, if we add more people to the world economy and develop new productivity multipliers, we’ll continue to raise living standards.

Books: Abundance: The Future is Better Than You Think, The Life You Can Save, Progress: Ten Reasons to Look Forward to the Future, The Great Escape: Health, Wealth, and the Origins of Inequality

Prior: There is a meaning in life that we eventually discover.

Update: There is no meaning inherent in life, and we have to construct our own meaningful life. Building a fulfilling life means finding a purpose larger than ourselves — be it religion, science, capitalism, philanthropy — and pursue it with a group of people who share the same goals.

Throughout childhood and college, we are provided with external objectives — get into a good college, graduate with high marks — that lend a structure and purpose to our lives. Many young people transitioning to the working world struggle without a framework leading to an apparent end objective. It would be nice to think a meaning will eventually be dictated to us, but alas, it won’t be. Instead, we need to construct our meaning and guiding principles for our existence.

Books: Man’s Search for Meaning, The Happiness Hypothesis: Finding Modern Truth in Ancient Wisdom, Principles, Zen and the Art of Motorcycle Maintenance: An Inquiry into Values

Prior: Natural = better.

Update: Natural things — hatred of outsiders, violence, starvation, disease, short lives, poverty — are often horrible. Many of humanity’s greatest achievements — long lives, eradication of diseases, the ending of famine through GMOs, scientific collaboration, helping people on the other side of the world we’ll never see, peaceful relations between countries — have come when we pushed back against genetic programming or innate impulses.

The argument that natural = better is lazy and should never be taken at face value. The natural condition of humanity is far more painful than what we’ve gained through engineering. Morality, altruism, and reason may be natural in the sense these traits resulted from evolution, but they are not our first response to most situations. Further progress depends on our individual and societal ability to develop better alternatives to the natural approach.

Books: The Moral Animal, Genome: The Autobiography of a Species in 23 Chapters, The Righteous Mind: Why Good People Are Divided by Politics and Religion, The Demon-Haunted World: Science as a Candle in the Dark

Prior: When you have achieved success and comfort in life, you owe nothing more to society.

Update: Those of us in the developed world have an unimaginably high standard of living, significantly higher than even the wealthiest people 100 years ago. On the other hand, there are still people in extreme poverty, with every day a struggle for survival. By donating just a small percentage of our income, so tiny we won’t even notice, we can significantly raise the living standards of families in the poorest countries.

Donating makes us feel better about ourselves as it can help lend a purpose to our work even if we aren’t working at a non-profit. Also, philanthropy will eventually improve our lives because when one human gains, we can all benefit. An important point to raise is that when donating to charity, be research your choices as some charities are literally 1000 times as effective in improving living standards as others. Maybe we have earned all our wealth, but even if that were the case, it would not abdicate us from our responsibility of helping our fellow humans.

Books: The Life You Can Save, The Moral Animal, The Great Escape: Health, Wealth, and the Origins of Inequality, Principles

Prior: Technology is purely beneficial.

Update: Technology can have a positive or negative impact, depending on how it is used. While original ideas of the internet and computers were utopian, the past few decades have revealed many of the drawbacks of the tech that pervades our lives. These include a decrease in social capital, technology addiction, increasing isolation and loneliness, increasing rates of mental illness, devices designed to hijack our biological drives, the spread of misinformation used to justify hate crimes, rising inequality, and more echo chambers leading to extremism.

These are no one’s fault, instead, they are the result of unquestioningly adopting every new social media app or device without thinking through the consequences. The idea of social media — connecting everyone around the world — may be neutral, but the implementation, through companies that depend on ad revenue has led to adverse outcomes. The negative consequences are a result of our biological drives, designed for survival hundreds of thousands of years ago, coming in contact with 21st-century technology.

Thanks to our evolutionary past, we are optimized to seek rewards, long for social approval, dislike outsiders, and crave distraction. Tech takes advantage of all these, mostly to increase revenue. However, we can use the same tendencies towards positive ends, for example, social learning and gamification of health training. The critical point is we need to examine how we use our devices so we can reach a balance where tech improves our physical lives and human connections instead of replacing them.

Books: Irresistible: Why We Can’t Stop Checking, Scrolling, Clicking, and Watching, Bowling Alone: The Collapse and Revival of American Community, Zucked: Waking Up to the Facebook Catastrophe, Team Human

Prior: Pure rationality leads to the best decisions.

Update: Using only reasoning does not lead to the best decisions. The optimal choices are made when we combine emotions with conscious thinking. At the extreme end, people who have lost all emotion and are entirely rational have difficultly even arriving at a decision let along making a positive choice.

In a society where the majority of our decisions are influenced by and impact humans, we need emotion as a guide. Our thought processes are started by emotions, which then provide course corrections as our rational, slower system evaluates the options. Without the crucial influence of emotion, our brains get stuck examining the pros and cons of each choice. Our initial, fast reaction is also not a decent way to make decisions as it uses shortcuts that don’t serve us well in an information-dense environment.

Similar to how we need emotions to guide reason, we need humans to guide the decisions of machines. As we’ve found, ceding all control to machines will not result in unbiased decisions or optimal outcomes. Computers, after all, are designed by humans and, therefore, we need people to review their choices. There is still a need for a human in the machine decision-making loop, just as there is still a need for emotion in the human decision-making system.

Books: Descartes Error: Emotion, Reason, and the Human Brain, The Social Animal, Army of None: Autonomous Weapons and the Future of War, The Happiness Hypothesis: Finding Modern Truth in Ancient Wisdom

Prior: Humans are born genetically identical blank slates, and all behaviors are learned through our environment.

Update: All humans are born with different genetic profiles, DNA, which results in differences between individuals and between groups. We should not view humans as blank slates that are entirely shaped by their environment, nurture, and we should not ignore the differences between groups, such as those between men and women. Genetics is not destiny as the environment plays a role in development. Still, our DNA does make us better suited to some behaviors and more likely to think in specific patterns.

To understand our thoughts and behaviors, we need to look beyond our environment and towards our genetic background. Evolution has produced brains and bodies designed to succeed in our evolutionary environment, which was considerably different than the modern world. We can use evolutionary biology to understand our (sometimes negative) natural inclinations and determine when they will not serve us well.

If we claim that humans are born identical, then we will not get the help those less genetically-inclined to succeed in society the help they need. Acknowledging DNA differences should let us better understand our fellow humans and lead to higher levels of empathy. Further, genetics reveals that all humans can act morally and altruistically, so we need to create environments in which those traits can thrive. Altruism may have evolved because it helped our ancestors to survive through reciprocal altruism, and it can continue to help us advance our interests today.

Books: The Moral Animal, Genome: The Autobiography of a Species in 23 Chapters, The Strange Order of Things: Life, Feeling, and the Making of Cultures, The Righteous Mind: Why Good People Are Divided by Politics and Religion

Prior: We should avoid circumstances that we are not comfortable with and ideas that challenge us.

Update: Our society rewards resiliency, the ability to recover and thrive after failure, and avoiding anything uncomfortable harms our resilience. Recent decades have seen a shift towards protecting people, especially youths, from things believed to harm them, such as controversial opinions, dirty conditions, and demanding physical exertion. The evidence now suggests this protectionism is probably damaging people as it makes them fragile.

The hygiene hypothesis states that by avoiding all germs and allergens in our youth, our bodies’ immune systems overreact when we finally encounter them, which may lead to an increase in allergies. The counter to this is to let kids play in all sorts of environments (including the outdoors). Similarly, adults need to eat a varied diet and be exposed to non-sterile environments to cultivate a healthy microbiome, which affects both mental and physical health. Not all germs are harmful, and we should not be blindly eradicating them all.

As an analogy to our aversion to varied environments, we’ve acquired an aversion to challenging ideas. College campuses now routinely disinvite speakers because of their beliefs, and employees are fired for stating scientific evidence that does not line up with the “correct” (meaning comfortable) views. The way to deal with controversial opinions is not to dismiss them but to debate them and let students decide how to think on their own. Suffering without reason is negative, but going through challenging situations can improve our mental and physical health along with our resiliency.

Books: The Coddling of the American Mind: How Good Intentions and Bad Ideas Are Setting Up A Generation for Failure, Can’t Hurt Me: Master Your Mind and Defy the Odds, Man’s Search for Meaning, I Contain Multitudes: The Microbes Within Us and a Grander View of Life

Prior: External events are innately positive or negative.

Update: Any event that happens in the world is neither innately positive nor innately negative. It’s our internal reaction to events that determines how we perceive them. Our mindset determines how we process sensory information and then colors events as good or bad. As an example, when exercising, you experience — through your senses — high levels of physical pain, yet you can enjoy (or at least bear) the exertion because you have a favorable view of exercise.

Whenever an external event happens, if you slow down to examine your feelings, you’ll see they are the product of your attitude. By changing how you consciously process events, you can change how you feel about the occurrences. You may grow irate over a colleague’s tendency to point out flaws in your work, but by reframing her comments as a genuine attempt to help, you can feel gratitude towards her (and use her feedback to improve).

The idea that mindsets influence how we feel about external events is not new, as ancient practices such as Buddhism figured this out thousands of years ago, but it does seem to have been forgotten. The core idea of mindfulness is examining your feelings, reactions, and thoughts. To be mindful, you don’t need to meditate for hours a day, only take the time to process sensory information before you react consciously. Conscientiousness can reduce your stress by limiting adverse reactions and increasing your gratitude (or at least decreasing your animosity) towards other people.

Books: The Happiness Hypothesis: Finding Modern Truth in Ancient Wisdom, Man’s Search for Meaning, Why Buddhism is True: The Science and Philosophy of Meditation and Enlightenment, Feeling Good: The New Mood Therapy

Prior: Addressing climate change will require new technological breakthroughs.

Update: We already have all the technologies needed to make the switch to 100% clean energy and reverse the worst effects of our industrial activities. Addressing climate change is not a matter of inventing new solutions, but of gaining worldwide governmental agreement to implement the best we have. Past legislation, such as the Clean Air Act or the Montreal Protocol, demonstrates that effective laws can have a profound effect on improving the environment and, consequently, our health. Climate change is the most significant challenge of this century, and humans have to come together — as we’ve done before when addressing diseases or environmental issues — on a world scale.

When discussing climate change, there are negatives, but also successes and reasons for optimism. People will not be inspired to act if they think the situation is hopeless and are told only of far-off consequences they can not influence. Therefore we should focus on solutions that already work and the symptoms we now experience when discussing climate change. Moreover, now that the economic situation has flipped in favor of clean energy, markets can work to tackle climate change by rewarding the most sustainable companies.

Furthermore, although individual actions by themselves have a small impact, collectively, the actions of large groups of consumers can drive change. When people make a minuscule change in their lives, we should not tell them it is pointless, but encourage them to continue and involve others. On the international level, we need to make rational choices based on the best science — including expanding the safest, steadiest, most reliable source of clean energy, nuclear — and securing international agreements. Discussing problems is necessary to ensure we solve the right issue. Still, science has decisively concluded the problem and discussions should transition from the problem to how to implement evidence-based, existing approaches.

Books: Drawdown: The Most Comprehensive Plan Ever Proposed to Reduce Global Warming, Climate of Hope: How Cities, Businesses, And Citizens Can Save the Planet, The Sixth Extinction: An Unnatural History Abundance: The Future is Better Than You Think,


Our updated beliefs should not be considered correct. They only represent the best worldview given the data. As science makes new findings and as we observe more successes and failures, we should be continuously adapting our beliefs. One of the best methods I’ve found to update beliefs is by reading widely and extensively, then reflecting on the information and identifying shared findings that represent the best knowledge humans have. Whatever your system for learning knowledge, remember that being incorrect is not a failure, the mistake is not updating your belief as new data emerges.

I welcome feedback and constructive criticism. Reach me in the responses, or on Twitter @koehrsen_will.



Will Koehrsen

Senior Machine Learning Engineer at Cortex Sustainability Intelligence