Charlie Munger · "The Psychology of Human Misjudgment"
Harvard, 1995. A lawyer-turned-investor in his seventies stands up and announces he is going to "romp through" a list: twenty-four standard causes of human misjudgment. No slides. He has never taken a psychology course — he says so twice from the stage, almost with relish — and he talks for more than ten thousand words. Somewhere in the middle he loses his own numbering: he goes from Fourth straight to Sixth, says "Nine" twice, and near the end pulls up short — "Oh no, no no, I've skipped one."
The man is Charlie Munger, vice-chairman of Berkshire Hathaway.
His hardest example is a doctor. At the leading hospital in Lincoln, Nebraska, this surgeon sent gallbladders down to the pathology lab by the basketful — and they kept coming back normal. Munger asked one of the old doctors who eventually helped remove him from the staff: was the man calculating that a few maimings a year would buy him a good living?
"Hell no, Charlie. He thought that the gallbladder was the source of all medical evil, and if you really love your patients, you couldn't get that organ out rapidly enough."— Charlie Munger, "The Psychology of Human Misjudgment," 1995
That is the center of the talk. The dangerous person is not the cynic; it is the sincere one. Incentives don't make people lie. Incentives make people believe.
But the list is not the point. Halfway through, Munger stops himself: "This is the most important question in this whole talk. What happens when these standard psychological tendencies combine?"
The answer is the word he coined: lollapalooza. Tupperware parties, Moonie conversion, Alcoholics Anonymous, the open-outcry auction, the board of directors of a major American company — none of these flatten people through one tendency. Four or five push the same way at the same time. "What you should search for in life is the combination, because the combination is likely to do you in."
Thirty years on, the report card is split down the middle.
The method half held. In passing, Munger overturned the standard reading of Milgram's obedience experiment. Everyone takes it to show that authority makes people obey. Munger said no: the experimenter gave a reason ("we need this to look for scientific truth"), and the shocks escalated one small step at a time. What was actually doing the work was justification, gradualism and contrast — not the order. In 2012, Haslam and Reicher reached the same conclusion in PLOS Biology, noting that of Milgram's four standard prods, the one pure command — "You have no other choice, you must go on" — is the one that makes participants refuse. Munger was seventeen years early, without the course.
The exhibits half lost several pieces. For social proof he used the Kitty Genovese murder: "I don't know, 50, 60, 70 of them just sort of sat and did nothing." In 2007, American Psychologist went to the killer's trial transcripts and found no evidence that there were 38 witnesses, no evidence that any witness saw the murder, and no evidence that witnesses remained inactive.
And in 2005, an eighty-one-year-old Munger rewrote the whole talk at double the length. The publisher's preface says plainly that the revision was "made from memory unassisted by any research." He removed Zimbardo's Stanford prison experiment. He left Kitty Genovese exactly where she was.
That is an item on his own list.
Munger never gives the doctor's name.
He gives the place: the leading hospital in Lincoln, Nebraska. He gives the action: sending "bushel baskets full of normal gallbladders" down to the pathology lab. And he gives the lag: "with that quality control for which community hospitals are famous, about five years after he should've been removed from the staff, he was."
The gallbladders were healthy. Which is to say: for years, a technically skilled surgeon was cutting sound organs out of people.
Munger knew one of the old doctors who took part in removing him — the families were friends. So he asked the question everyone wants to ask: was the man thinking, here's a way to exercise my talents and make a high living by doing a few maimings and murders every year, along with some frauds?
The answer is the coldest line in ten thousand words:
"Hell no, Charlie. He thought that the gallbladder was the source of all medical evil, and if you really love your patients, you couldn't get that organ out rapidly enough."— Charlie Munger, "The Psychology of Human Misjudgment," 1995
Munger turns straight to the room full of future lawyers: "Now that's an extreme case, but in lesser strength, it's present in every profession and in every human being."
In 1995 Charlie Munger was vice-chairman of Berkshire Hathaway and a Harvard Law graduate, class of 1948, back at his old university to talk about psychology — a subject in which, as he tells the room himself, he had never taken a course. Nor in economics. (In passing he says "I'm 70 years old," which is one reason different sources date this talk to 1994 or 1995.)
He was not there to deliver a paper. He was there to settle an account.
What he took away from Harvard Law, Munger says, was "terrible ignorance." He could see that human irrationality was extreme and, more importantly, patterned — and he had no theory to deal with it. So he built his own psychology, "partly by casual reading, but largely from personal experience." Much later he stumbled into Bob Cialdini's Influence, which "filled in a lot of holes in my crude system."
And in that year, behavioral economics was still a slightly disreputable thing to do. Kahneman and Tversky's prospect theory was sixteen years old; Kahneman's Nobel was seven years away, Thaler's twenty-two. Munger planted his flag in one sentence:
"And I came here because behavioral economics. How could economics not be behavioral? If it isn't behavioral, what the hell is it?"— Charlie Munger, "The Psychology of Human Misjudgment," 1995
The audience was Harvard Law. And four years earlier, in 1991, Salomon Brothers had blown up over rigged Treasury auction bids; Buffett stepped in as chairman to salvage it, and Berkshire was a major Salomon shareholder. All three names from that scandal — chairman Gutfreund, trader Mozer, general counsel Feuerstein — appear in this talk as exhibits, and Munger discusses them in the tone of a man saying "I know both men."
One more thing to say up front: this is not a polished script. He is working from "rough notes," he loses his own numbering repeatedly, and the surviving transcript still carries the stutter where the tape was flipped. Ten years later, reading those transcripts, he decided to rewrite the whole thing.
He opens by explaining where the system came from — not learned, but collided with — and then: "let me romp through as much of this list as I have time to get through." Title: 24 Standard Causes of Human Misjudgment.
First, incentives. He says he has been "in the top 5% of my age cohort all my life in understanding the power of incentives, and all my life I've underestimated it." The example is Federal Express: the integrity of the whole system depends on every package being moved through one central hub, fast, every night, and the company could not make it happen. They tried moral suasion. They tried everything. Then somebody noticed the night shift was paid by the hour. Pay them by the shift, and the problem dissolved.
Third, incentive-caused bias — the gallbladder doctor. Munger scales it to institutions: after the Defense Department had had enough experience with cost-plus-percentage-of-cost contracts, the republic made writing one a felony. From which he draws a conclusion that sounds odd and is entirely practical: the people who invent things like cash registers, "which make most behavior hard," are "some of the effective saints of our civilization." He also corrects Shaw's line that every profession is a conspiracy against the laity — "it's not so much conspiracy as it is a subconscious, psychological tendency."
Fourth, consistency and commitment, which he calls a superpower, and which produces the most vivid image of the night:
"…the human mind is a lot like the human egg, and the human egg has a shut-off device. When one sperm gets in, it shuts down so the next one can't get in."— Charlie Munger, "The Psychology of Human Misjudgment," 1995
This spares no one, he says, not even the deans of physics: according to Max Planck, genuinely new physics was never accepted by the old guard; a new guard simply arrived that was "less brain-blocked by its previous conclusions." Then he turns to the students shouting outside: "they aren't convincing us, but they're forming mental change for themselves, because what they're shouting out they're pounding in." Hence a harsh verdict — educational institutions that encourage too much of it are "in a fundamental sense, they're irresponsible institutions." And the closer: the Chinese POW brainwashing system beat everyone else's because it maneuvered people into tiny commitments first and built from there. "That worked way better than torture."
The list rolls on. Social proof: Kitty Genovese; and the Nobel-sharing economist who watched Berkshire outperform year after year and called it a two-sigma event, then three, then four, all the way to six — "better to add a sigma than change a theory." Deprival superreaction: the Munger dog, lovely and harmless, which could only be made to bite you by reaching for something already in its mouth; and the neighbor's three-foot pine tree that turned a 180-degree view of the harbor into 179 and three-quarters, producing a feud like the Hatfields and McCoys. Envy: "two out of the 10 commandments," and blank in the textbook index — "It's not greed that drives the world but envy."
Then authority, and a throwaway line nobody noticed at the time. He does Milgram (there have been, he says, 1,600 psychological papers on it), then a worse number: put a pilot and a co-pilot in a simulator, have the pilot do something an idiot co-pilot would know will crash the plane, and the trained co-pilot — who knows he is not to allow a crash — lets it crash 25% of the time. Then he adds, almost to himself: "It's not quite as powerful as some people think, and I'll get to that later."
He does. Two-thirds of the way in, he hits pause on his own talk: "Now, the time has come to ask two or three questions. This is the most important question in this whole talk. What happens when these standard psychological tendencies combine? What happens when the situation, or the artful manipulation of man, causes several of these tendencies to operate on a person toward the same end at the same time? The clear answer is the combination greatly increases power to change behavior."
This is lollapalooza, and the examples come fast: Tupperware parties, which "made billions of dollars out of a few manipulative psychological tricks"; Moonie conversion methods; Alcoholics Anonymous — "a 50% no-drinking rate outcome when everything else fails," four or five mechanisms aimed at a good end; the McDonnell Douglas evacuation test (the government demanded realism, so they put old people in a darkened hangar twenty-odd feet above a concrete floor with flimsy rubber chutes, injured about twenty people in the morning, and ran it again in the afternoon — twenty more injuries and one severed spinal column, permanent); the open-outcry auction, "just made to turn the brain into mush"; and the American board of directors.
And Milgram is on that list. Munger says of it: "It's been widely interpreted as mere obedience, but the truth of the matter is that the experimenter who got the students to give the heavy shocks in Milgrim, he explained why. It was a false explanation." And, he adds, the experimenter worked the subject up — "tiny shock, a little larger, a little larger." So commitment and consistency and the contrast principle were both working in favor of the behavior, on top of authority. "So again, it's four different psychological tendencies."
"What you should search for in life is the combination, because the combination is likely to do you in."— Charlie Munger, "The Psychology of Human Misjudgment," 1995
He ends by running the list in reverse, as engineering: the medical schools' "watch one, do one, teach one"; the rules of the Constitutional Convention — total secrecy, no recorded votes until the final one, because otherwise "everybody would have been pushed into a corner by his own pronouncements and his own oratory." The capstone is Darwin, who always paid extra attention to disconfirming evidence:
"…here's a guy that, by all objective evidence, is not nearly as smart as I am and he's in Westminster Abbey? He must have tricks I should learn."— Charlie Munger, "The Psychology of Human Misjudgment," 1995
So he started "wearing little hair shirts like Darwin." And then the last question: if this thought system has great value not widely recognized, what should the educational system do about it? "I am not going to answer that one now. I like leaving a little mystery."
Munger told those examples from memory. Go back to the original papers and the gap runs in both directions.
Cialdini's ask-for-something-outrageous-then-back-off study is the one psychology experiment Munger recounts in detail. Here is the 1995 version from the stage: he asked people on a campus to take juvenile delinquents to the zoo, and one in six agreed; he asked a different group to devote two afternoons a week to delinquents, and got 100% refusal; then he backed off — "Would you at least take them to the zoo one afternoon?" — and "He raised the compliance rate from a third to a half. He got three times the success by just going through the little ask-for-a-lot-and-back-off."
A third to a half is not three times, and it does not match the one-in-six he had just said. He garbled it. The written version ten years later fixes it: "This raised Cialdini's former acceptance rate of 1/6 to 1/2—a tripling."
The original paper is Cialdini, Vincent, Lewis, Catalan, Wheeler and Darby, Journal of Personality and Social Psychology, 1975. Experiment 1 ran on 72 people, stopped while walking alone on university walkways, randomly split three ways, 24 per cell:
In headcount, the famous tripling is twelve people versus four. The large request was to serve as an unpaid counselor at the County Juvenile Detention Center, "two hours of your time per week for a minimum of two years." The small one was chaperoning a two-hour zoo trip. The authors themselves note in the discussion that the "small" request was objectively not small: it asked subjects to be responsible for an unspecified number of juvenile delinquents of unspecified age, in a public place, for two hours, outdoors, in winter.
Two details that didn't make the stage and that change the weight of the thing. First, there is a footnote: only Experiment 1 was run in winter; Experiments 2 and 3 ran in spring or summer, which "may account for the somewhat higher compliance rates in the small request only controls" there. The researchers knew the number was sensitive to the season. Second, and this is the one that matters: the study measured saying yes. The experimenter asked, "Would you be interested in being considered for one of these positions?" — not whether anyone actually turned up at the zoo that afternoon.
On one point Munger was right and could easily have been wrong. That exposure control was Cialdini's test of the contrast explanation: if merely having seen a big request, making the small one look small, were enough, the mechanism would be contrast rather than reciprocation. It did not reach conventional significance. Contrast is a major standalone item on Munger's own list, and he could have filed the study there. He didn't. He picked the right mechanism.
What circulates today as "Munger's talk" is mostly not the 1995 event. It is the 2005 rewrite prepared for Poor Charlie's Almanack: the live transcript runs about 10,700 words, the rewrite about 24,300. The publisher's note contains one crucial sentence: the extensive revision by Munger in 2005 was "made from memory unassisted by any research."
Munger listed four reasons not to publish it, each more lucid than the last. He conceded his psychological knowledge "came only from skimming three psychology textbooks about fifteen years ago," that he knows "virtually nothing about any academic psychology later developed," and that he was about to criticize academic psychology at length anyway. He knew an amateur intruding on professional territory would look arrogant — he borrowed an old classmate's phrase for it, "the shoe button complex," named for a family friend who spoke in oracular style on all subjects after becoming dominant in the shoe button business. The fourth reason is blunter: "I might make a fool of myself." He published it.
Three changes are worth recording. One: 24 tendencies became 25, and the new Twenty-Fifth is Lollapalooza — in 1995 it was a question raised late in the talk; in 2005 it is promoted to a tendency in its own right. Two: Zimbardo and the Stanford prison experiment vanish entirely. In 1995 that study was the main exhibit for role theory; in the 2005 text the words "Zimbardo" and "Stanford" do not appear once. Three: Kitty Genovese stays, and is stated more flatly than in the spoken version — "the inaction of a great many bystanders led to the death of Kitty Genovese."
Meanwhile his claim about Milgram got sharper and less gracious. In 2005 he writes that the experiment "demonstrated extreme ignorance in the psychology professoriate right after World War II"; that almost any intelligent person holding his checklist would, "by simply going down the checklist," have seen about six powerful tendencies acting in confluence; and that it took "over a thousand psychological papers" for the professoriate to get his experiment "only about ninety percent as well understood."
That is a large bet: that a system assembled from memory would beat a thousand papers to the answer. Thirty years on, we can settle it.
PARTLY HELD UP · as of 2026-09
The method half won, and won more handsomely than it deserved to: Munger's reinterpretation of Milgram beat the formal literature by seventeen years, and he had already deleted what would become the field's most famous collapse. The exhibits half lost several pieces: the "38 witnesses" he used for social proof has been dismantled from the archives, and the one experiment he recounted in detail survives thirty-five years of meta-analysis only on the verbal-compliance half — which happens to be exactly what it measured. The sharpest part is that when he rewrote the talk in 2005 he left the bad exhibits in place, committing the error his own list describes.
September 2007: the 38 witnesses came apart. Rachel Manning, Mark Levine and Alan Collins published "The Kitty Genovese Murder and the Social Psychology of Helping: The Parable of the 38 Witnesses" in American Psychologist, working from the trial transcripts of Winston Mosley and associated legal documents. The conclusion is in the first line of the abstract: the story is "not supported by the available evidence" — no evidence for the presence of 38 witnesses, none that witnesses observed the murder, none that witnesses remained inactive. They classify it as a modern parable: retold because its moral is clear, not because it is accurate.
But it matters where the blow lands. The authors explicitly separate "the robust bystander research tradition" from "the story of the 38 witnesses." Latané and Darley's experiments stand; diffusion of responsibility is real. What collapsed is the signature case, not the tendency. Munger's "50, 60, 70 of them just sort of sat and did nothing" is precisely the version with no archival support — though in fairness, when he rewrote the talk in 2005, Manning and colleagues were still two years from publishing.
2012: the one experiment he recounted got weighed. Thomas Hugh Feeley, Ashley Anker and Ariel Aloe published a meta-analysis of thirty-five years of door-in-the-face research in Communication Monographs. The result splits in two. In Feeley's words, "the door-in-the face strategy does indeed work much better than a simple request for compliance in securing a verbal agreement to help, but that agreement to help doesn't often lead to actual helping behavior" — practically, it "may get people to agree to a donation, for instance, but it is not effective in getting them to follow through with their verbal commitment." The effects are small either way: the university's own release puts the correlation coefficient at .126, "demonstrating a small effect." (Sources differ on which of the two outcomes that figure attaches to, so nothing on this page rests on it.)
Set that beside the 1975 paper and the true size of Munger's example becomes visible. Cialdini's Experiment 1 measured whether people said "Would you be interested in being considered for one of these positions?" — a verbal yes, which is exactly the half that survives. So the zoo study was not overturned. It is that what it measured is much narrower than the audience assumed. The claim that a small maneuver can steer what people actually do is the part that never got support.
Also 2012: his Milgram reinterpretation was formally ratified. S. Alexander Haslam and Stephen Reicher published "Contesting the 'Nature' Of Conformity: What Milgram and Zimbardo's Studies Really Show" in PLOS Biology, proposing engaged followership: participants are not blindly obeying but identifying with the cause the experimenter represents and actively working toward it. The key evidence is the prods. Of the four standard prods, the one pure order — "You have no other choice, you must go on" — is the one that makes participants refuse; what actually keeps them going is the scientific justification, "The experiment requires that you continue."
That is close to the academic edition of what Munger said in 1995: everyone reads obedience, and the truth is the false why, plus gradualism, plus contrast. The same paper also takes apart Zimbardo's prison study, showing he gave the guards explicit instructions — telling them at orientation, "You can create in the prisoners feelings of boredom, a sense of fear to some degree, you can create a notion of arbitrariness that their life is totally controlled by us" — rather than merely assigning roles. Which leaves a coincidence worth sitting with: the Stanford prison experiment is the exhibit Munger had quietly dropped in 2005.
Still open is lollapalooza itself. The claim that four or five tendencies in confluence produce extreme outcomes is hard to falsify: after the fact, you can always find four or five on the list. Nobody had to point this out — Munger asked it on stage. "Isn't this list of standard psychological tendencies improperly tautological compared with the system of Euclid? That is, aren't there overlaps, and can't some items on the list be derived from combinations of other items? The answer to that is, plainly, yes." In 2005 he added that in a soft science "a significant amount of messiness is unfixable." That is candor, and candor is not verification. Thirty years on, the word has entered the working vocabulary of investors. It has not entered the psychology literature.
Which leaves the self-reference nobody can step around. A seventy-year-old man spent an hour at Harvard explaining how people are fooled by their own memory, their own spoken conclusions, their own failure to check. Ten years later, at eighty-one, he rewrote it from memory, unassisted by any research — having already coined the name for that behavior and predicted its consequence. He cut the right one. He kept the wrong one.
The most persuasive evidence for the checklist is the set of cuts it left on its own author.