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Joined August 2026
Charlie Munger thought McDonald's did a better job educating people than Harvard. He wasn't joking. In 2010, sitting next to Warren Buffett at Berkshire Hathaway's annual meeting, Munger explained why he considered McDonald's one of America's most underrated educational institutions. His argument had almost nothing to do with hamburgers. McDonald's takes people at the very beginning of their working lives. For many of them, it's their first real job. And before they move on, it teaches them things that are surprisingly difficult to teach in a classroom: show up on time, follow a system, deal with customers, take responsibility and do the job you're being paid to do. Munger had once made the same argument while speaking at a major university. He told the room: “I thought McDonald's succeeded better as an educator than the people in the university did.” His point wasn't that people stayed at McDonald's forever. It was almost the opposite. Many started there, learned how to function in a real workplace, and eventually moved on to much bigger jobs. Munger believed McDonald's deserved far more credit for that than it received. Then Buffett jumped in — and agreed. He said some of the most important lessons of his own life came when he was just 13 or 14 years old, working for a newspaper boss named Charlie Peterson. Long before Berkshire Hathaway. Long before he became one of the richest men in the world. Buffett was just a kid learning lessons from his first boss that he still remembered decades later. Munger and Buffett were making the same point from opposite ends of extraordinary careers: sometimes the place that teaches you how to work isn't a university. It's the place expecting you to show up on time tomorrow morning.
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Ted Bundy murdered at least 30 women across 7 states. He drove them in a Volkswagen Beetle - same car, same smile, same routine. The FBI called him the most organized serial killer in American history. Netflix made a $30 million series. Zac Efron played him on screen. He was executed in Florida in 1989. His little brother Rich was 12 years old, rafting rivers with him on weekends, sitting in the back seat of that same Volkswagen, thinking his big brother had everything figured out. In the video below, Rich Bundy tells the story of the moment he realized Ted had sent him home early to go murder someone. They were at the airport. Rich was upset - Ted had cancelled their plans out of nowhere, no explanation. As they waited to board, Rich glanced over at his brother's face. Ted was staring into the distance. Horrified. Disgusted. By something only he could see. Rich didn't understand it then. He does now. Ted had been loading the Volkswagen with rope, handcuffs and a crowbar before their trips together. He would pick up young women on the same roads they drove. Rich was in the back seat for some of those drives without knowing what the bag in the trunk was for. Ted sent him home that day because he felt the urges coming and didn't want his little brother in the car when it happened. That one decision broke Rich completely. He spent decades sitting alone in a camper, sometimes not leaving for three days at a time. Can't hold a normal life together. Says he's gotten used to jimmying his way through existence. Ted protected him from one night. The knowledge of what that night was destroyed the rest of his life anyway. Was Rich Bundy a victim of his brother, or did surviving that family come at a price nobody could have paid?
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Peter Scully was an Australian crminal sentenced to life in prison plus 129 years. His victims were children. The youngest was just 18 months old. He held young girls captive, subjected them to horrific abse, filmed his crimes, and distributed child exploitation material to offenders around the world. After fleeing Australia, he operated in the Philippines until authorities finally arrested him in 2015. When they caught him, prosecutors from 60 Minutes to the FBI called him the most depraved individual they had ever encountered in over two decades of law enforcement. In the video below, a reporter from 60 Minutes Australia sits face to face with Scully inside a Philippine maximum security prison - and describes it as the most disturbing moment of her 26-year career. She refused to watch his videos before the interview. She said once you see something like that you can't unsee it. Colleagues who did watch them were visibly traumatized for days afterward. Sitting across from him was worse than she expected. He was smug. Arrogant. He smiled at her questions. When she asked about remorse he paused, looked her in the eye and said: "That's a good question. Well done." She walked through the house afterward. Up the same stairs those children were taken up. In broad daylight. With a police officer beside her. She said even that was enough to make her skin crawl. There was a shallow grave in the yard. Interpol. The FBI. The Philippine National Police. It took three major law enforcement agencies to bring him down. What finally broke the case was a single local officer following a gut instinct nobody else believed in. The reporter said she got to go home after the interview. She wasn't sure how long his smugness lasted after she left. Some people sit across from you and you understand immediately that the word "monster" was invented specifically for them.
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In 1985, Carl Sagan sat in front of the United States Senate and described the weather of 2026. Not as prediction. As physics. Sitting across from him was a junior senator named Al Gore — who would later win the Nobel Prize, the Oscar, and build a climate investment fund worth over $36 billion repeating almost word for word what Sagan said that afternoon. Sagan opened with Venus. 470°C surface temperature. 900°F. Hot enough to melt lead. "Not because it's closer to the sun," he told the senators. "Venus actually reflects more light than Earth. It should be cooler." The reason it wasn't: carbon dioxide. A runaway greenhouse effect that turned a planet nearly identical to Earth into a furnace. Then he looked at the committee and said: we're running the same experiment here. The senators nodded politely. Then they went back to approving fossil fuel subsidies. What Sagan told Congress in 1985: Global average temperature will rise several degrees by mid-to-late next century. Local climates will redistribute. Glaciers will melt. Sea levels will rise. And the problem cannot be solved by any single nation — not even if the US and Soviet Union agreed on everything — without China. China, he said, had the world's largest coal reserves and was about to industrialize. Every sentence was correct. He also said something that got almost no coverage at the time: "The initial stages of global temperature increase — one region might benefit while another suffers." That is the sentence that explains the last 20 years of geopolitics. Canada's growing season expanding while Pakistan floods. Russia opening Arctic shipping lanes while Bangladesh disappears. The politics of climate was never going to be clean because the physics wasn't distributed evenly. Sagan mapped all of it from first principles, in a Senate hearing room, 41 years ago. The part nobody quotes He didn't say stop burning fossil fuels immediately. He said: "That has such severe economic consequences that no one will take it seriously." So he proposed something else — remove government subsidies from fossil fuels, accelerate solar, develop safe nuclear fission, and begin building international frameworks before the crisis made them impossible. That's not an environmentalist's speech. That's an economist's. Carl Sagan wrote 20 books. Cosmos was watched by 500 million people across 60 countries. He won the Pulitzer. The ideas in this testimony became the scientific foundation for a carbon market now valued at over $800 billion annually. He said one line at the end that nobody remembers. "We are all in this greenhouse together." In 1985, that was poetic. Now it's a weather report. The full testimony is free on YouTube. 17 minutes. Almost nobody outside of climate policy circles has watched it as a complete predictive model — laid out in plain language before any of it happened.
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Warren Buffett disowned his granddaughter in 2006, writing that he had never accepted her as his grandchild, legally or emotionally. Buffett has largely avoided publicly discussing what happened between them. In the video below, Nicole Buffett tells her side of the story. Nicole had grown up as part of the Buffett family after Warren’s son Peter adopted her. She visited Warren in Omaha, called him Grandpa, and Warren’s wife Susan even referred to Nicole as one of her “adored grandchildren.” But being the granddaughter of one of the richest men in the world never meant living like one. Warren paid for her education, but Nicole didn’t have access to his fortune. She worked with children at Family Human Services in San Francisco and built her own life while carrying one of the most famous surnames in American business. Then their relationship fell apart after Nicole appeared in The One Percent, a documentary about wealth inequality. She later received a letter from Buffett telling her that he had not emotionally or legally adopted her as a grandchild, and that the rest of his family had not adopted her as a niece or cousin either. One detail made the letter even more painful. Buffett signed it simply “Warren.” Nicole still had a card from only a year earlier signed “Grandpa.” One of the richest men in the world had spent years as her grandfather. Then a letter told her he no longer considered himself one. Do you think Buffett had the right to draw that line, or did he take it too far? Save the video to finish Nicole’s story later, and follow for more heartbreaking stories from behind the lives of the world’s most famous billionaires.
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David Bowie sold over 140 million records. He invented three different musical personas that each defined an entire era. Rolling Stone called him the most influential artist of the 20th century. He turned down a knighthood from the Queen of England because he didn't think he deserved it. In the mid-1970s he was also consuming so much cocaine that he later said he remembers almost nothing from that entire period. Not the albums. Not the tours. Not the interviews. This is one of those interviews. In the video below, the most creative mind in rock history sits across from a journalist and explains, completely unprompted, how to destroy a city. Black noise, he says. A specific frequency that shatters everything it hits. Available in the French Patent Office until recently for about three or four dollars. A small device could kill four people in a room. A large one could level an entire city. The interviewer stares at him. Bowie moves on to Machiavelli. Then Diane Arbus. Then Frank Zappa naming his son Moon Unit. Then his own son Zowie. Then his wife Angela's thesis on everything. Then a book about the Trans-Siberian Express he may or may not be writing. At one point he offers the interviewer a part in his next show. This is the same man who wrote Heroes in a single afternoon. Who created Ziggy Stardust, Aladdin Sane, and the Thin White Duke from scratch. Who produced Iggy Pop's two greatest albums while barely sleeping. He survived the decade. Cleaned up. Made ten more classic records. The cocaine almost took all of it. The talent was just bigger than the damage. Was he a genius who almost destroyed himself, or did the destruction make him the genius he became?
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In 1986 a guy got kicked out of every casino in Vegas for counting cards. So he flew to Hong Kong with $180,000 and started betting on horses instead. He walked away with almost $900 million. It was Bill Benter. He realized horse racing was just another counting problem same math, more moving parts. He and a partner built a computer model that estimated the true odds of each horse. If his numbers showed an edge, he bet. If not, he skipped it. That’s the whole trick: Expected value. EV = p · b − (1 − p) Only bet when the probability of winning × the potential payout is greater than the chance of losing. What’s even crazier is that Benter once gave a 45-minute lecture explaining the math behind his system. That recording was never supposed to become public. And almost nobody knows it exists. This is the lecture that professional bettors and hedge fund analysts studied. The answer is in this video.
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Steve Jobs literally predicted the iPhone, the Internet, AI and the next 50 years of technology in a single speech from 1983:
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Sam Altman invited Peter Thiel to Stanford to teach a lesson most entrepreneurs still ignore. His message? “Competition is for losers.” In his famous 2014 Stanford lecture, Thiel explained why the biggest businesses don’t win by fighting competitors. They win by building something nobody else can offer. Stop asking how to beat your competition. Ask yourself: What can I build that makes competition irrelevant? Because the goal isn’t to win the same game. It’s to create a game nobody else can play.
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Your revenue forecast runs on an equation that has zero exact solutions gilbert strang, mit 18.06 linear algebra, lecture 16, projection matrices and least squares. then the problem. three months of data, reaching 1, 2, 2. no straight line passes through all three, zero exact solutions exist. then the fix. solve the normal equations, 3c plus 6d equals 5, 6c plus 14d equals 11. answer, d is one half, c is two thirds, one best line. then the leftover. that line predicts 7 sixths, 5 thirds, 13 sixths. actual was 1, 2, 2. the miss never hits zero, only its smallest size. then the transfer. that equation, a transpose a times x equals a transpose b, runs every model forecasting revenue, pricing risk, or reading gps. watch the moment he calls this equation the most important one in statistics. the line was never going to hit every point. the math was how close it could still get.
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A bbb credit rating is a coin that only remembers its last flip john tsitsiklis, mit 6.041sc, probabilistic systems analysis, lecture 16, markov chains. then the matrix. s&p's own data, 1981 to 1996, a bbb company stays bbb 82.49 percent of the time in one year. nothing further back matters. then the slide. 5.81 percent of bbb companies get downgraded within that year, to bb, b, or ccc. real risk, ignored by most bond buyers. then the default. outright default inside that year hits only 0.17 percent of bbb companies, 34 times rarer than a plain downgrade. then the transfer. a markov chain predicts next year from this year's grade alone. the real risk in a bbb bond is the slide, not the cliff. watch the moment he shows the next state depends only on where it stands now, not how it got there. the rating was never a cliff edge. it was always a slope, graded in percent per year.
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In 1995 a 31-year-old told his parents there was a 70 percent chance they would lose every dollar they put in. They invested $245,573 anyway. Never sold, those shares would be worth over $80 billion today. "What's the Internet?" was his Cuban stepfather's first question. Everything the son told them is in a 47-minute interview that has about 33,000 views on YouTube. The stepfather is Mike Bezos, one of 14,048 Cuban children flown to Miami without their parents between 1960 and 1962. He landed alone at 16. The son he adopted is Jeff Bezos. The interview was filmed in San Antonio in May 2001. Jeff explains why he quit Wall Street and how he spent his parents' money. Five months later Amazon stock hit its post-bubble low, about 95 percent under its 1999 peak. His method has a name that, in his words, only a nerd would give it: the regret minimization framework. Age 80. Picture yourself at 80 and pick the choice with fewer regrets. Most of them, he says, are things people never did. It is why he quit mid-year and walked away from his annual bonus. Write down the odds. He gave Amazon a 30 percent chance when a typical startup had about 10. Planning on failure, he says, takes the pressure of self-doubt off. Kill risk first. Spend the early money on the biggest problem, then the next one. Stress is a skipped phone call. It comes from not acting on something you control. The first call or email cuts most of it. Skip the gold rush. In 1849 doctors quit medicine to pan for gold. In 1999 people quit their jobs to do something on the internet. That almost never works, he says. Anyone who bought the Nasdaq at its March 2000 top waited 15 years to get back to even. "I knew that if I failed I wouldn't regret that, but I knew the one thing I might regret is not ever having tried." That is Bezos at 37. His boss had walked him around Central Park for two hours and asked him to take 48 hours before deciding. In 1999, he says, you could raise $60 million for an internet idea with one phone call and no business plan. His own round took about 60 pitches to raise $1 million. The next time a friend asks you to put money into their idea, ask for the odds you lose all of it. If they can't give you a number, keep your money.
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In 2005 Bill Gates and Warren Buffett told 92 Nebraska students how they could legally live the rest of their lives without paying a dollar of income tax. Only students could ask. Neither man saw a question in advance. One lunch with Buffett sold for $19 million in 2022. Fifty-five minutes of him and Gates answering these students is free. That September Forbes ranked them first and second in America: Gates at $51 billion, Buffett at $40 billion. The video is Nebraska public television's cut of that afternoon at the University of Nebraska-Lincoln, Buffett's old school. Between jokes about Halo 2 and losing at ping-pong to a nine-year-old, they lay out six rules. The newspaper test. Before any decision, imagine a smart, unfriendly reporter writing it up for your family tomorrow. Anything close to the line is out. The blank calendar. Gates said one of his favorite lessons from Buffett was a calendar with almost nothing in it. You have to be good at saying no. No committees. Buffett said brilliant investment decisions never come out of a large committee. Poll enough people and you buy what everyone already owns. You are the asset. Getting comfortable with public speaking, he said, pays off for 50 or 60 years, and avoiding it costs you just as long. Omissions. His worst mistakes never hit a statement: about $10 billion in profits from deals he understood and skipped, or made too small. The unsold gain. Tax arrives when you sell. His version: hold the stock, borrow against it every year to live on, and let the estate pay off the loan. He said he could have done it for decades and called it very unfair. His 1989 letter to shareholders has the math. Double $1 twenty times, selling after each double at a 34 percent tax, and you end with about $25,250. Hold through all twenty doubles and sell once, and you keep about $692,000. Same returns. The only difference is when the tax gets paid. "They have really taken care of the rich." That is Buffett on the cuts that took capital gains and dividends to a 15 percent tax. Gates answered: "I go along with that wholeheartedly." Everyone in his office paid payroll tax on their first $90,000 plus income tax, and he said their rate was often the same as his, maybe higher. Every paycheck you get loses 7.65 percent before income tax starts. A stock that rises and stays unsold has paid nothing. Billionaires do not avoid income tax by earning less. They avoid it by selling less. Price the tax bill before you cash out your next winner.
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winning this auction is the exact moment you are guaranteed to have overpaid ben polak, yale university, econ 159 game theory, lecture 24. then the setup. a jar of coins goes up for bid in a real classroom, about 28 students call out numbers, from 1 cent to 5 dollars. then the number. the winning bid is 5 dollars. the jar holds 2.07 dollars. the winner paid 2.93 more than it was worth. then the reason. out of 28 guesses, the winner is whoever guessed highest, not closest. the highest guess is the most overpriced one by construction. then the transfer. in real federal offshore oil lease auctions, when 7 or more companies bid on one lease, the average winner's profit was negative. watch the moment he tells the winner what she owes, the gap between her guess and the real number in the jar. more bidders did not make the price accurate. it made the overpayment bigger.
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Warren Buffett is worth about $145 billion. His daughter asked him for $41,000 after she had a baby. He told her to go to the bank. In the clip he says the rule out loud. Other people think they won the lottery with a trust fund that takes care of them for life, "and five generations thereafter." He wasn't raised that way. He didn't raise them that way. The kitchen is what that rule looked like at home. Susie had a new baby and a kitchen too small for a table. She asked for a loan, not a gift. He said no. The bank. Her father. In the end her mother saw the house and had the kitchen redone herself. Warren still didn't write the check. None of the three finished college. None of them will inherit the fortune. In 2024 he put them in charge of giving almost all of it away after he dies. They get the job. They do not get the money. He would not lend his own daughter $41,000 for a kitchen. He is leaving the three of them to hand out about $145 billion to other people. Was the $41,000 a lesson, or did a father with $145 billion just not want to spend it on her?
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you're not quiet. you're scared. and everyone in the room can tell. you call it "introverted." "thoughtful." "i let my work speak for itself." cute. your work has never spoken a word in its life. while you wait for someone to notice you, the guy with half your brain just got your promotion. and he deserved it more than you, because he showed up. harsh? Warren Buffett was worse than you. the only a+ in ben graham's class. the sharpest investing mind of the century. and the idea of standing up in front of people made him physically throw up. so he hid. exactly like you. back row, mouth shut, waiting to be discovered. he signed up for a speaking course. wrote the check. then got scared and cancelled it before the first class. a future $100 billion man, beaten by a room full of strangers. the difference between him and you is what came next. months later he walked back in and slammed $100 in cash on the desk so he couldn't chicken out again. sat in a room of grown men who shook too hard to say their own name. stayed. before the course was over, he'd proposed to his wife. warren buffett, on the dale carnegie course: "I had the intellect to succeed, but I did not have the persona." he was scared and did it anyway. you're scared and you're still scrolling.
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In 1995 a 31-year-old told his parents there was a 70 percent chance they would lose every dollar they put in. They invested $245,573 anyway. Never sold, those shares would be worth over $80 billion today. "What's the Internet?" was his Cuban stepfather's first question. Everything the son told them is in a 47-minute interview that has about 33,000 views on YouTube. The stepfather is Mike Bezos, one of 14,048 Cuban children flown to Miami without their parents between 1960 and 1962. He landed alone at 16. The son he adopted is Jeff Bezos. The interview was filmed in San Antonio in May 2001. Jeff explains why he quit Wall Street and how he spent his parents' money. Five months later Amazon stock hit its post-bubble low, about 95 percent under its 1999 peak. His method has a name that, in his words, only a nerd would give it: the regret minimization framework. Age 80. Picture yourself at 80 and pick the choice with fewer regrets. Most of them, he says, are things people never did. It is why he quit mid-year and walked away from his annual bonus. Write down the odds. He gave Amazon a 30 percent chance when a typical startup had about 10. Planning on failure, he says, takes the pressure of self-doubt off. Kill risk first. Spend the early money on the biggest problem, then the next one. Stress is a skipped phone call. It comes from not acting on something you control. The first call or email cuts most of it. Skip the gold rush. In 1849 doctors quit medicine to pan for gold. In 1999 people quit their jobs to do something on the internet. That almost never works, he says. Anyone who bought the Nasdaq at its March 2000 top waited 15 years to get back to even. "I knew that if I failed I wouldn't regret that, but I knew the one thing I might regret is not ever having tried." That is Bezos at 37. His boss had walked him around Central Park for two hours and asked him to take 48 hours before deciding. In 1999, he says, you could raise $60 million for an internet idea with one phone call and no business plan. His own round took about 60 pitches to raise $1 million. The full interview is free on the Academy of Achievement's YouTube channel. The next time a friend asks you to put money into their idea, ask for the odds you lose all of it. If they can't give you a number, keep your money.
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An MIT-trained Harvard psychologist ran an experiment that exposes a bug in how you think about money. Drive across town to save $100 on a $200 stereo? Most people say yes. Drive across town to save the exact same $100 on a $31,000 car? Most people say no. Same $100. Same drive. Same person. The only thing that changed is what the $100 is standing next to. His name is Dan Gilbert, Harvard psychologist, author of Stumbling on Happiness. He didn't build this from theory — he built it on a rule from 1738. Daniel Bernoulli's original idea for making any decision under uncertainty was simple: multiply the odds of an outcome by how much it's worth to you. Expected value = probability × value. Gilbert's argument is that we're bad at both halves of that equation. We misjudge the odds. And we misjudge the value even worse. The car stereo isn't a one-off trick. It's mental accounting — your brain doesn't evaluate $100 as $100. It evaluates $100 as a percentage of whatever it's attached to. Save 50% on a stereo feels like a win. Save 0.3% on a car feels like nothing. The dollar amount never moved. Same failure shows up with a lost ticket. Lose a $20 ticket on the way to a show, and most people won't buy a replacement. Lose a $20 bill on the way to the same show, and most people buy the ticket anyway. Economically, you're $20 poorer either way. Psychologically, replacing the ticket feels like paying twice for one seat. It shows up again with a wine list. Put a $27 bottle between an $8 bottle and a $33 bottle, and it looks reasonable. Change what's sitting next to it, and the same $27 bottle can look expensive or cheap without a single cent changing. Here's the part that should worry you more than any of the individual examples. Every one of these comparisons — the stereo, the wine, the wallet, the ticket — disappears the moment you actually use what you bought. You don't drink the $8 and $33 bottles next to the $27 one. You just drink the wine. The comparison that decided your purchase evaporates the second the purchase is real. Your brain isn't running the math wrong by accident. It's running a completely different equation than the one it thinks it's running — and the input it's optimizing for vanishes right after you pay.
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Professional poker player Phil Ivey won $9.6 million at the Borgata. The casino paid him, then sued to get it back. At London’s Crockfords, he won another £7.7 million. They refused to pay. In the video below, Ivey says his job is to play the game, find a weakness in the casino and use it to win. He calls the casino his opponent and points out that it spends millions of dollars protecting its games. He wanted a specific brand of cards, a Cantonese-speaking dealer and the same decks reused. The casinos agreed. His playing partner, Cheung Yin Sun, asked the dealer to rotate certain cards, presenting it as a matter of luck. The cards had tiny differences along their backs. Once high-value cards faced one way and the others faced the opposite way, those differences helped identify what was coming next. Ivey never marked the cards. The dealer handled them. But the casino didn’t understand what those requests were doing to the odds. He called it an advantage. The casinos called it cheating. In 2017, the UK Supreme Court ruled against him: persuading the dealer to arrange the cards crossed the line. The casino had approved his requests while expecting to win. Ivey knew something about its own cards that it didn’t. Was he cheating, or should a casino know its own game before accepting someone’s money?
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THE MIT PROFESSOR WHOSE CALCULUS STUDENTS SAY NO ONE HAS EVER MADE THEM FEEL MORE CAPABLE INTRODUCES LINE INTEGRALS BY PROVING THAT SOMETIMES THE GEOMETRIC INSIGHT SOLVES IN THREE LINES WHAT THE CALCULATION TAKES HALF A BLACKBOARD TO FINISH This is Denis Auroux, MIT, 18.02 Multivariable Calculus, Fall 2007. His students consistently rank him among the most beloved teachers in the mathematics department. He opens with one claim - vector fields and line integrals are completely different from double integrals and it actually helps to forget everything from last week. He starts with vector fields. At every point in the plane you have a vector. Wind maps are vector fields. Gravitational fields are vector fields. The field xi plus yj points radially outward from the origin and grows with distance. The field minus yi plus xj rotates everything counterclockwise at unit angular velocity. A particle of fluid in that field traces a perfect circle and returns to its starting point in exactly two pi units of time. Then work. When a force pushes a particle along a trajectory the work done is the force dotted with the displacement. For a straight line and constant force this is simple multiplication. For a curved trajectory where the force changes at every point you cut the path into infinitely many tiny pieces, dot the force with each tiny displacement, and sum. That sum is the line integral. Then computation. Parameterize the curve with a single variable. Express x and y in terms of that variable. Replace dx and dy with their derivatives times dt. The two-dimensional integral collapses into a single ordinary integral you already know how to solve. Then the geometric shortcut. The line integral equals the integral of the tangential component of the force along the curve. If the force is always perpendicular to the curve the work is zero with no calculation needed. The field xi plus yj on a circle of radius a gives zero immediately because the radial force is always perpendicular to the circular path. The field minus yi plus xj on the same circle gives two pi a squared immediately because the force always points exactly along the path with magnitude a. Watch the moment he computes the same integral two ways side by side. The geometric method takes three lines. The parametric method takes half a blackboard. Same answer. The insight about perpendicularity or parallelism does in seconds what algebra does in minutes. A mechanical engineering student I know rewatched this lecture before a problem set on conservative force fields. Said it was the first time the dot product felt like it was measuring something physical rather than producing a number.
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