On the evening of 11 September 1960, a corporal in the Ethiopian Imperial Bodyguard ran through Rome without shoes.
Abebe Bikila was the son of a shepherd. The shoes he brought to the Games had worn out and the pair he bought in Rome raised blisters, so he ran the marathon barefoot. His coach, Onni Niskanen, had told him to make his move a little more than a kilometre from the finish, where the course passes the obelisk of Axum, taken from Ethiopia by Italian troops and re-erected in the capital of the country that had invaded his own. Bikila made the move there and won in 2:15:16, a world record, the first Olympic gold medal won by a sub-Saharan African in any sport.
What happened afterward is the part worth studying. Kip Keino, Filbert Bayi, Henry Rono, Derartu Tulu, Paul Tergat, Haile Gebrselassie, Kenenisa Bekele, Eliud Kipchoge. Six decades of East African distance running, in a region that had won nothing before 1960 and has since owned the event. Nothing changed in the bodies of Ethiopians and Kenyans between 1959 and 1961. What changed was that the thing had been done, and done by someone recognisable.
The question
I once watched a film in which a boy describes an ambitious project and his friend tells him it is impossible. The boy asks how he knows, and whether he has ever tried it. I no longer remember the film or the rest of the conversation. What stayed with me was the difference between the two positions. The boy is asking whether something can be done. His friend is answering from what he has seen.
A person says, “I cannot do that,” when what they mean is, “I have never seen anyone like me do that.” Those are not the same statement, and the difference between them is the subject of this essay.
The world we see becomes the world we expect
A child growing up around business owners may learn that starting a company is an ordinary thing to do. Another may encounter entrepreneurship only as something distant, dangerous, or belonging to people from a different social world. Neither is born with a map of the futures available to them. They build one, out of family, schooling, class, and whoever happens to be standing nearby.
Albert Bandura named the mechanism. Self-efficacy is the belief that you can perform a particular task, and two of its sources are succeeding at something yourself and watching somebody else succeed. A person who has never seen anyone from their circumstances build a company does not necessarily lack ambition. They have a smaller set of examples from which to assemble one.
This is why the sentence is so often about identity rather than skill. A person may know perfectly well that someone else has built a company, entered a profession, or attended a university they admire, and still find the example irrelevant to their own life. He had money. She had connections. He was already different. She was exceptionally talented.
Sometimes those explanations are correct. The problem is that they become automatic, so that every example is disposed of before it can do any work.
Why a new example often changes nothing
In 1997 Penelope Lockwood and Ziva Kunda published a study in the Journal of Personality and Social Psychology on how outstanding performers affect the way people see themselves. An exceptional person affected participants' self-views only when the field was one the participant cared about. Within that, the direction of the effect flipped depending on whether the success looked reachable. When it did, because the participant still had time or believed their ability could improve, the example produced inspiration. When it did not, the same example produced self-deflation.
The same person. Opposite effect. The variable is not the strength of the example but whether the viewer can see a path from where they stand to where the other person is standing.
So the dismissals deserve more respect than they usually get. “He had money” is often an accurate report that an example failed a test, and when an example fails that test it does not merely fail to inspire. It pushes the person further down than they were before they saw it.
Which means the standard advice to surround yourself with people who have achieved enormously can be exactly wrong.
The three conditions
Put the evidence together and it converges on one rule with three conditions attached. An example moves you only if it is in your domain, close enough to be reachable, and near enough to be real to you.
Domain means the specific thing, not the general category. Reachable means one or two steps ahead, not ten. Real means the person is close enough that you cannot dismiss them as a different kind of creature.
Fail any one and nothing happens. Fail the second badly enough and the example does damage. Garance Genicot and Debraj Ray formalised that middle condition in 2017: aspirations moderately above a person's current standard of living encourage investment, while aspirations far above it produce frustration. Too low gives you fatalism, too high gives you paralysis, and both look identical from outside because both produce a person who does nothing.
The inventors
Alexander Bell, Raj Chetty and their co-authors tracked more than a million American inventors, linking patent records to tax records and childhood test scores.
Children who grew up in a neighbourhood or family with a high rate of innovation in a particular technology class went on to patent in that same class. Not in innovation generally. In that class. Girls were more likely to invent in a class if they grew up in an area with more women inventing in it, and male inventors nearby had no such effect on them. For boys the pattern ran the other way.
The distributions of third-grade maths scores for boys and girls are almost identical. The high-scoring girls became inventors far less often than the high-scoring boys. The authors calculate that if women, minorities and children from low-income families invented at the rate of high-income white men, America would have four times as many inventors as it does.
The effects were specific to gender and to technology class, which rules out general explanations such as school quality and points at something far narrower.
The colleagues
Ramana Nanda and Jesper Sørensen, writing in Management Science in 2010, used a matched employer-employee dataset to ask whether people are more likely to become entrepreneurs when their colleagues have been entrepreneurs before. They are.
Two details make the finding useful rather than merely encouraging. The effect was strongest among people with little exposure to entrepreneurship elsewhere in their lives, and about half as strong for the children of entrepreneurs. Exposure was not teaching anyone how to run a business. It was adding an option to a list, and where the option was already there, more exposure bought little.
Vera Rocha and Mirjam van Praag examined roughly ninety thousand Danish employees who had worked at a startup, publishing in the Strategic Management Journal in 2020. Women who joined a company founded by a woman went on to found companies at higher rates. Men showed no equivalent effect. The influence was concentrated among women who had lacked previous contact with entrepreneurs, and was stronger when founder and employee shared characteristics such as age, education, and being a mother.
Doba
About 2,000 people in 64 villages in Doba, a remote district east of Addis Ababa, took part in a randomised trial. One group watched hour-long documentaries about people from similar communities who had climbed out of poverty by their own effort, without government or NGO help. A second watched an entertainment programme. A third was only surveyed. Nobody in the films had become rich. They were farmers and small traders who had improved their circumstances by working, saving, and making better decisions.
Six months later, aspirations had risen among those who watched the documentaries and had not moved in the other two groups. Savings rose by 97 birr against a control average of 182. The number of children between six and fifteen enrolled in school rose by 0.21, an increase of 21 percent on a baseline of just over one child per household. Measures of locus of control moved in the same direction.
One detail makes the result hard to explain away. None of the four documentaries featured a person with significant formal education, and none gave schooling as a reason for their success. School enrollment rose anyway. The audience was not copying actions it had seen. Something had changed in how those households understood their own options.
The researchers returned five years later and the effects were still there, in farm investment, in children's education, and in assets, explained by a lasting rise in what people believed their lives could contain. The study was published in the Quarterly Journal of Economics in 2026.
One hour of video, watched once, still visible in household accounts half a decade later. The qualification is the part to keep. The effects were largest for people who already held somewhat higher aspirations before the screening, which is the second condition appearing again. New examples are not a substitute for everything else a person lacks. They enlarge the field of what a person will consider, which is worth a great deal and is not the whole of it.
The four-minute mile is a better example than the story we tell about it
Athletics gives us the most quoted case of a limit that turned out to be conventional rather than physical. Roger Bannister ran a mile in 3:59.4 in Oxford in May 1954. John Landy ran 3:58.0 forty-six days later. The usual telling is that a psychological wall came down and the impossible became ordinary.
The idea that informed observers considered four minutes impossible came largely from sportswriters, and Bannister said so himself in his 1955 memoir. Four minutes was a round number sitting a second and a half under a record that had stood unusually long because the war interrupted competition. Two Swedish runners had already taken five seconds off the mile between 1942 and 1945. If Bannister had not run it that spring, someone would have run it that summer.
Now look at what happened afterward. It took ten years before a high school student did it. Jim Ryun ran 3:59.0 in 1964, and three years later he held the world record at nineteen. Then nothing. From 1967 to 2001, not one American high schooler broke four minutes. Alan Webb ended that drought in 2001 and his time is still the high school record. In the first fifty years after Ryun, ten American high schoolers went under four minutes. Between 2020 and 2025, twenty did.
That shape is the useful one. The barrier did not dissolve the moment the first man crossed it. It held for another thirty-four years at the level below, then gave way everywhere at once. What changed in the second period was not belief. It was training volume, coaching, pacing, shoe technology, and races organised so that a teenager could be carried to the mark. Belief opened the question. The method answered it.
The same pattern is running now. Eliud Kipchoge went under two hours in Vienna in 2019, under conditions that did not qualify as a record. On 26 April 2026 in London, Sabastian Sawe ran 1:59:30 in an ordinary race, and Yomif Kejelcha finished eleven seconds behind him in 1:59:41, in the first marathon he had ever run. Both beat the world record that had stood that morning.
Two men under two hours on the same day, in the same race, and one of them a debutant. Whatever that barrier was, it was not sitting inside one man's head. Kejelcha is Ethiopian, and sixty-six years separate his run from Bikila's.
Real, learned, untested
Some limits are real. A person may not have the money for a particular school, the access to a market, or the skill a job requires. They may face discrimination, political restriction, or obligations that make a choice impossible. Other limits are learned. I cannot do that because I have never seen anyone like me do it. And some have been internalised so far that they no longer feel like limits at all. Even if I could, I would not belong there.
This is why the language of breaking free misleads, if it implies every obstacle is psychological. The better question is which limits are real, which are learned, and which have never actually been tested.
The test
Start by writing the limit down as a sentence. Most limits are never stated, which is exactly why they are never examined. Then name the evidence you actually hold for it. It is usually one bad experience, or somebody's opinion, or an observation about a category of person rather than about the task.
Then audit your reference group against the three conditions, because that group is your ceiling. Not the people you admire from a distance, who fail the reachability test and may be quietly costing you. The people one or two steps ahead of you in your specific problem. If there is nobody in that position anywhere near you, that is the constraint to fix first, and it is a practical problem rather than a psychological one.
Then build the smallest thing that produces evidence either way, and decide in advance what you are willing to lose. The question is not whether you can build a successful company. It is whether you can find one customer. Then whether you can deliver. Then whether you can do it again. The ambition has not shrunk. The question has become answerable.
A person who has never tried something holds a prediction. A person who has tried, learned from the result, and tried again holds evidence. The evidence may be disappointing. It is still a different thing from assuming the door is shut.
One move runs the other way. If you have already crossed a line the people around you have not, you are now their evidence. The Doba documentaries worked because the people on the screen were close enough to count. Chetty's girls responded to women inventing nearby. Rocha and van Praag's employees responded to a founder who resembled them. Whether your work is legible to people who resemble you determines whether it functions as an example at all. It is an obligation with a cost attached.
What we have never tested
Beliefs about possibility are not fixed simply because they are familiar. They can be revised, and the revision holds for years. They can also fail to be revised. A person may become more ambitious and still meet a real barrier, or see a new example and correctly conclude it does not apply.
What moved in Doba was not talent or capital. It was the range of futures people thought were available to them.
The boy in the film asks how you know, and whether you have ever tried. That is more than a challenge to pessimism. It is a challenge to the way conclusions get formed.
We mistake the boundaries of our experience for the boundaries of possibility. The task is not to pretend limits do not exist. It is to learn which ones are real, which ones are learned, and which ones we have never actually tested.