Charlie Munger

Munger's whole thing is mental models. The idea is simple: instead of being an expert in one field, you learn the core concepts from as many different fields as possible — psychology, biology, physics, economics, history — and then use that whole toolkit to think about problems.

He calls it a latticework of mental models. It sounds like a self-help concept.

It's actually how he consistently made better decisions than almost everyone around him. On investing, he pushed Buffett away from his old mentor's approach — which was basically "find dirt-cheap companies and flip them fast" — toward something more durable: find the best businesses in the world and hold them forever.

The key word he uses is moat. A business so dominant that competitors can't touch it.

Think Coca-Cola. He was also deeply influenced by psychology, particularly the ways humans reliably fool themselves.

He gave a famous talk called "The Psychology of Human Misjudgment" listing 25 ways our brains get things wrong. Reading it once will change how you make decisions.

Sam Altman

Altman is a prolific early-stage investor who backs deep tech and moonshot ideas. His portfolio through YC and personal investments includes hundreds of companies.

His personal bets tend toward civilizational-scale technology — nuclear fusion, longevity research, AI safety. He has said he thinks the most important investments of the next decade will be in energy and AI.

He also holds significant OpenAI equity (though the exact structure is complex given it was a nonprofit converted to capped-profit).

Charlie Munger

Invert. Always invert.

That's his most famous rule — borrowed from the mathematician Jacobi. Instead of asking "how do I succeed?" ask "what would guarantee failure, and then avoid those things." It sounds obvious.

Almost nobody actually does it. He believes the secret to a good life and good investing is the same: figure out what you want to avoid, avoid it relentlessly, and most good things follow.

On wealth: getting rich isn't the hard part — keeping it is. Most people blow up by using borrowed money, getting greedy at the top, or panicking at the bottom.

Don't do those things. On decisions: only make the big bet when you're very sure.

Be patient for a long time, then move fast when the opportunity is obvious.

Sam Altman

Altman believes we are approaching AGI — artificial general intelligence — and that it will be the most transformative and potentially dangerous technology humans have ever built. He thinks the right response is to build it carefully rather than cede the frontier to those who might not.

He argues that the returns from AI will be so large they will need to be distributed broadly to prevent catastrophic inequality. He has floated ideas around universal basic income funded by AI productivity.

Charlie Munger

Munger's approach to risk: don't take risks you don't understand, and don't take risks you don't need to. He kept things simple.

He concentrated into a small number of businesses he understood deeply. He never used borrowed money.

He kept large cash reserves. His view on diversification was almost the opposite of what most financial advisors tell you — he thought spreading money across 50 stocks was an admission that you hadn't done enough homework.

If you've done the work, you concentrate. If you haven't, maybe don't invest at all.

Sam Altman

Altman has said that playing it safe at this moment in history is the most dangerous thing he could do. His belief: AGI is coming whether OpenAI builds it or not — the only question is who builds it and with what values.

That conviction makes conventional risk aversion feel irresponsible to him. He holds large personal positions in nuclear fusion companies and longevity biotech — bets that could return 1000x or go to zero.

He has said that any genuinely interesting bet carries existential downside risk. That is what makes it interesting, not a reason to avoid it.

Charlie Munger

Munger lived in the same house in Los Angeles for most of his adult life. He was famously frugal — not in a miserable way, but in a "I genuinely don't care about most things money buys" way.

He flew commercial until fairly recently. He read obsessively.

He described himself as a book with legs. His children joked that he was more interesting to talk to than almost anyone alive, but would only engage on topics he found intellectually stimulating.

He donated massively to education — hundreds of millions to Harvard Law School, the University of Michigan, and other institutions, often with very specific conditions attached. He designed buildings as a hobby and funded their construction himself.

He died at 99 worth around $2.6 billion — extraordinary by any measure, and somehow modest given he sat next to one of the richest men in history for 45 years.

Sam Altman

He has written about sleeping 8 hours, exercise, not scheduling meetings before 11am, eating the same lunch every day, and blocking large chunks of uninterrupted time for thinking. He is a known prepper — he has said he owns land, gold, guns, and antibiotics in case civilization collapses, which is a mildly alarming admission from the CEO of the company building AGI.

Charlie Munger

See's Candies. In 1972, Munger convinced a reluctant Buffett to pay what seemed like an expensive price — $25 million — for a California candy company.

Buffett thought it was too much. Munger held firm.

See's has since generated over $2 billion in profit for Berkshire, basically funding dozens of other acquisitions. It also taught Buffett the single most important lesson of his career: paying a fair price for a great business beats getting a cheap price for a mediocre one.

That one deal changed the entire direction of Berkshire Hathaway.

Sam Altman

OpenAI and ChatGPT. The launch of ChatGPT in November 2022 was the most consequential product launch in tech in at least a decade.

It brought AI from a niche technical field into mainstream awareness overnight and made OpenAI the fastest-growing AI company in history. Altman navigated the transition from nonprofit to commercial entity, secured $13 billion from Microsoft, and built a company valued at $157 billion within five years.

Charlie Munger

Munger is famous for avoiding mistakes more than for making spectacular wins — his whole philosophy is about not doing stupid things. But he's admitted to a few.

He said Berkshire was too slow to move into BYD, China's electric vehicle company, despite knowing it was exceptional for years before they finally bought in. He also held too much Wesco Financial for too long when the money could have been put to better use elsewhere.

His most honest self-criticism: he wished he had moved faster when the evidence was already clear. For a man who spent his career warning others about psychological biases, he wasn't immune to them.

Sam Altman

Being fired by his own board in November 2023 — and the board's subsequent reversal. Whatever actually happened in those five days is still murky.

What is clear is that the board lost control of the situation the moment it became obvious that without Altman, most of the company would leave. The board members who voted to fire him are gone.

Altman is back with more power. The episode revealed real governance problems at one of the most consequential companies in history.

Charlie Munger

Charlie Munger grew up in Omaha — same city as Buffett, but they didn't know each other yet. His father was a lawyer.

So was his grandfather. Charlie became one too, but he was clearly more interested in figuring out how the world worked than in courtrooms.

He studied math at the University of Michigan, got drafted into World War II, trained as a meteorologist, and somehow ended up at Harvard Law School without ever finishing an undergraduate degree. Harvard took him anyway.

He graduated in 1948 and moved to California to practice law. He was good at it.

He was also quietly building a real estate business on the side that made him more money than law ever did. He and Buffett met at a dinner in Omaha in 1959.

Munger was 35. Buffett was 28.

By the end of the night, Buffett was trying to convince Munger to go into investing full time. It took about a decade.

Munger ran his own investment partnership from 1962 to 1975 — returned 24% annually while the market did 6.4%. Then he fully merged his career with Buffett's at Berkshire, where he stayed until his death in 2023.

Sam Altman

Sam Altman dropped out of Stanford in 2005 to co-found Loopt, a location-sharing startup. Loopt was acquired in 2012 for $43 million — not a huge exit but enough to establish him as a serious founder.

He then became president of Y Combinator in 2014, succeeding Paul Graham. Under Altman, YC expanded from a small cohort model to a much larger operation with global reach, including backing Airbnb, Dropbox, Stripe, and hundreds of others in its portfolio.

In 2019, he stepped down from YC to become CEO of OpenAI. The company launched ChatGPT in November 2022, which became the fastest-growing consumer application in history — 100 million users in two months.

In November 2023, the board fired him. The entire company revolted.

Microsoft — OpenAI's biggest investor — nearly hired him to run a new AI division. Five days later, he was reinstated with a restructured board.

OpenAI's valuation hit $157 billion by 2024.

Charlie Munger

Munger's main stage was Berkshire Hathaway, where he served as Vice Chairman from 1978 until he died. His role was hard to define on paper — he didn't run a fund or manage a portfolio.

What he actually did was talk to Buffett. That was worth a trillion dollars.

Before Berkshire, he ran his own investment partnership from 1962 to 1975 that crushed the market. He also controlled Wesco Financial, a small insurance and financial company he ran as a personal Berkshire subsidiary from 1973 to 2011, until Berkshire fully absorbed it.

Outside finance, he was obsessed with architecture — he personally designed several buildings, including a dormitory at the University of Michigan that his own architecture school rejected for violating design principles. He funded it anyway.

Sam Altman

OpenAI (CEO). Y Combinator (former president).

Loopt (co-founder, acquired 2012). Personal investments via Sam Altman Fund and early-stage bets.

Notable: invested early in Stripe (now worth $70B+), Helion Energy (nuclear fusion), Retro Biosciences (longevity). Also holds equity in Anthropic indirectly.

Charlie Munger

University of Michigan, mathematics — left for World War II without graduating. US Army Air Corps, meteorology training.

Harvard Law School, JD 1948 — admitted without an undergraduate degree, which Harvard is apparently capable of when it wants to be.

Sam Altman

Stanford University — studied computer science. Dropped out in 2005 after his sophomore year to found Loopt.