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Learning & Living

Education, decisions, habits, wellbeing and mental models.

4 Ideas · 9 Books · 4 Essays · 57 questions

This field is about the practical side of a good life. It asks how to decide, learn, work and change your habits. Its questions are personal, but many of the answers come from psychology, philosophy, economics and mathematics.

The pieces here include mental models, book reviews and personal essays. A mental model is a simple rule of thought that you can apply in many situations. The reviews look at popular self-help and career books and check their claims against research. The essays are personal and do not claim to be science. They end with questions for you to think about, not with a quiz.

Start with inversion, which means asking what would make a plan fail and then avoiding it. The dichotomy of control helps you decide where to put your effort. The after-action review gives you four questions for learning from any project. Then read the review of Eric Barker’s book, which tests common advice about success against studies.

Start here

The best first reads in this field, in this order.

  1. IdeaIntro

    What Is Inversion? Thinking Backward to Avoid Mistakes

    Ask yourself how to succeed at something, and the answers are often vague. One change to the question makes the answers concrete and quick to find. You learn that change, how to use it step by step on a real plan, where a famous quote about it really comes from, and when the method stops helping.

    6 min read≈ 1,350 words3 questions

  2. IdeaIntro

    What Is the Dichotomy of Control?

    Why do the Stoics say the aim matters more than the hit? You learn how Epictetus, who spent years as a slave, divided life into two parts, and how people have used that division from a prison camp to a job interview. You also see where it is too simple.

    8 min read≈ 1,650 words3 questions

  3. IdeaIntro

    What Is an After-Action Review?

    Most teams finish a project and move straight on to the next one, and then they repeat the same mistakes. The US Army built a simple habit to stop this, and companies and hospitals later copied it. You learn the four questions at its heart, how to run one after a real project, what the research says it achieves, and why it fails when people fear blame.

    6 min read≈ 1,370 words3 questions

  4. BookIntro

    "Barking Up the Wrong Tree" by Eric Barker: Summary and Review

    Should you follow the rules, be nice, never quit and believe in yourself? Eric Barker checks six pieces of common success advice against research. You learn which pieces hold up, which fail, what the book's own evidence can and cannot show, and who should read it.

    9 min read≈ 1,980 words5 questions

  5. EssayIntro

    Graham Weaver's Life Advice: Go Where Your Energy Is, Not Your Fear

    When you think about a big change in your life, which inner voice should decide? You learn what Graham Weaver, a Stanford teacher and investor, told graduating students in 2024: his three promises, the nine-lives exercise and why he warns against the words "not now". You also see where his advice needs a second look.

    7 min read≈ 1,480 words

Everything else in Learning & Living

Intro

BookLearning & Living

"Mastery" by Robert Greene: Summary and Review

Robert Greene's Mastery says great skill comes from a long apprenticeship, not talent. What the book argues, where it is weak, and how to read it.

9 min read≈ 2,020 words5 questions

BookEconomics & Business

"Principles" by Ray Dalio: Summary and Review

Ray Dalio's rules for facing reality, learning from mistakes and deciding together, explained, with the critics' view of the culture they built.

9 min read≈ 1,890 words5 questions

BookArts, Music & Language

"The Creative Act" by Rick Rubin: Summary and Review

Rick Rubin's book on creativity as a way of paying attention: its main ideas, the four phases of a project, and where its vague, spiritual language fails.

9 min read≈ 2,070 words5 questions

Intermediate

IdeaMathematics

What Is the Secretary Problem?

How to pick the best option when you see them one at a time and cannot go back. The 37 percent rule, worked through with ten flats, and its limits.

7 min read≈ 1,520 words3 questions