Michael Mauboussin's Advice on Writing: How to Find Your Edge as a Writer

Michael Mauboussin has been in the investment business for over 30 years. He heads Consilient Research at Counterpoint Global, part of Morgan Stanley. He has taught at Columbia Business School since 1993, winning the Dean's Award for Teaching Excellence twice. He chairs the board of trustees at the Santa Fe Institute.

He has written five books and dozens of research papers that circulate among professional investors like samizdat. His writing makes complex topics in decision science, probability, and market behavior accessible without sacrificing rigor.

His process draws from a What Got You There interview, a Farnam Street conversation on decision-making, and his writing archive.

Writing Is Thinking

Mauboussin identifies writing as fundamentally about understanding. "To be an effective writer, especially in the investment world, it means you have to understand. That is the foundation upon which all this is built." He has been consistent about this for over thirty years of teaching security analysis at Columbia Business School.

The experience repeats itself: he thinks he understands something, begins writing about it, and realizes he has no idea what he is doing. Writing forces a return to first principles, poking at spots of weakness and getting into depth. The gaps in your understanding become visible the moment you try to explain them on paper. That visibility is the entire point.

His preferred style is what Steven Pinker calls "classic style" - peers looking into the world together, describing concrete things. "It's almost like I put my arm around the reader and we say, let's talk about what we see." Not teacher to student. Not expert to novice. Two people gazing at the same landscape, one pointing things out.

The Decision Journal

Mauboussin's most practical writing tool: a decision journal. Before making a consequential decision, write down what you expect to happen, why you expect it, and your physical and emotional state at the time of the decision.

"It prevents something called hindsight bias." After an outcome is known, your memory rewrites the decision-making process to make the outcome seem inevitable. The journal provides "accurate and honest feedback of what you were thinking at that time."

This is not creative writing. It is forensic writing. You are creating a record that your future self can audit. The emotional state notation matters because decisions made while anxious, euphoric, or exhausted follow different patterns than decisions made in calm states.

Professional investors lose millions when they confuse a good outcome with a good process. The decision journal separates the two. Over time, patterns emerge. You discover which conditions produce your best thinking and which produce your worst.

Reading to Write

"When you read a lot, you start to realize the kinds of language that resonates with you. Who writes clearly? Who gets ideas into your mind? What is memorable to you?"

Mauboussin reads voraciously across disciplines. Not just finance. Biology, physics, psychology, history, complexity science. His work at the Santa Fe Institute exposed him to researchers studying complex adaptive systems, and those ideas permeate his investment writing.

He admires Michael Lewis and Matt Levine as exemplary clear writers. Lewis because he turns financial complexity into narrative. Levine because he turns financial complexity into humor. Both achieve the same result: ideas that stick.

The reading habit feeds the writing habit directly. Mauboussin uses what he reads in his own research, and he understands material better when he writes or speaks about it. The cycle is read, absorb, write, teach, repeat. Each stage deepens the understanding from the previous one.

The Multidisciplinary Edge

Mauboussin draws from biology, psychology, physics, and complexity science to write about investing. This multidisciplinary approach is not decoration. It is his analytical edge.

When he writes about base rates in investment decisions, he draws on research from psychology. When he writes about competitive dynamics, he draws on ecology. When he writes about market behavior, he draws on complexity science. Each discipline offers models that finance alone does not provide.

Howard Marks takes a similar approach, importing concepts from psychology and history into his investment memos. The principle is the same. The writer who reads only within their field writes predictable analysis. The writer who reads across fields produces insights their peers cannot replicate.

Charlie Munger called this building a "latticework of mental models." Mauboussin has spent three decades building that lattice and translating it into prose that investment professionals use daily.

Teaching Reveals the Gaps

"It's one thing to think you know what something means. It's a very different thing to communicate and get that into the mind of another."

Mauboussin has taught at Columbia Business School since 1993. He started because he realized in his early years that technical financial skills were prerequisites but not the keys to investment success. What mattered was how investors made decisions under stress. That insight led him to explore psychological literature, which led him to teach a course connecting decision science to investing.

Teaching forced discipline. When you explain a concept to students, you discover which parts you genuinely understand and which parts you have been hand-waving through. The students' confusion is diagnostic. It reveals exactly where your explanation, and therefore your understanding, breaks down.

Writing and teaching reinforce each other. The research paper forces you to think clearly. The classroom forces you to communicate clearly. They are different skills with a shared dependency on genuine understanding.

Lawrence Gonzalez and the Education of an Editor

Mauboussin sent a manuscript of his book Think Twice to Lawrence Gonzalez, author of Deep Survival and a writing teacher at Northwestern. Most readers sent back polite notes - "great book, page 57 might be wrong." Gonzalez asked: "What kind of treatment would you like me to give this?" Then he line-edited the entire book. Mauboussin spent a full week going through the edits because Gonzalez was not just correcting - he was teaching writing along the way.

One example: Mauboussin used "error" and "mistake" interchangeably throughout the manuscript. Gonzalez went into the etymology. An error is doing something wrong when you should have known better. A mistake is doing something wrong when you may not have had reason to do it correctly. "I wrote a whole book about this and I had no idea." The lesson was not about those two words. It was about being more mindful of every word.

Gonzalez knows nothing about finance, which made him the perfect editor. He could ask the questions a lay reader would ask. He could flag every instance of jargon or technical shorthand that an insider would not notice. "Why are you using this technical term when a simpler term would do the same thing?"

Checklists for Analytical Writing

Mauboussin applies checklist methodology from his decision-making research to the writing process. Two types are relevant.

The do-confirm checklist: perform your normal analysis, then pause to verify you have covered all essential points. Have you examined the evidence from multiple angles? Have you considered the base rates? Have you acknowledged what could disprove your thesis?

The read-do checklist: used during difficult writing situations to guide systematic problem-solving. When you are stuck, the checklist provides structure that prevents you from abandoning rigor in favor of expedience.

"How do you become more systematic in applying what you know?" Checklists create consistent analytical quality rather than relying on inspiration or intuition.

Synthesis as Method

Mauboussin's signature contribution is cross-disciplinary synthesis. He reads about neurobiology and discovers that the number of synaptic connections in the brain follows an explosive growth and pruning pattern - massive upswing, then elimination of what is not used. He then finds the identical pattern in industry development: huge upswing in competitors, followed by a shakeout. Both systems search the space through proliferation, then prune to efficiency.

These connections do not happen by accident. They happen because he reads across biology, psychology, physics, and complexity science, always looking for patterns that transfer. "If I have this framework, it allows me to understand how and why this is happening. And we can see the repercussions from historical precedent."

He draws a practical lesson for writers: the Grossman-Stiglitz paper from 1980 proves that informationally efficient markets are impossible because gathering information has a cost, and that cost must be compensated. Apply that to writing: if you do the work of gathering domain expertise, you will find things to say. The market for ideas is not efficient. There is always more to discover. "The world always changes, and as a consequence, there are always nooks and crannies to be explored."

Key Takeaways

• Writing is thinking. The gaps in your understanding become visible on paper.
• Keep a decision journal. Record what you expect, why, and how you feel before the outcome.
• Read across disciplines. The multidisciplinary edge is real and compounding.
• Teaching reveals what you actually understand versus what you think you understand.
• Work with editors. Their brutality is the highest-leverage investment in quality.
• Use checklists. Systematic rigor beats inspiration.
• Do not trust intuition in domains with noisy feedback. Verify.

Mauboussin proves that analytical writing is a discipline with the same rigor as the analysis it describes. Read widely. Think carefully. Write precisely. Then let an editor show you where you failed, and do it again.

Sources: Mauboussin's What Got You There interview, Farnam Street on decision-making, and his writing archive. Athens is an AI writing editor.