ONE WILD WORLD — NEWSLETTER

Issue #025   ·   This Changed Everything   ·   May 2026

Almost everyone over the age of six can tell you the story. Columbus, the lone visionary, certain the Earth was round; a frightened, superstitious Europe convinced he would sail straight off the edge; a voyage that proved the doubters wrong. It is one of the most widely known stories in the whole of Western history. Almost every load-bearing piece of it is false — and the false pieces were not innocent mistakes. They were added later, deliberately, by people who found the truth insufficiently dramatic.

BY THE NUMBERS

c. 240 BC

When the Greek scholar Eratosthenes calculated the circumference of the Earth. His answer was off by only a few per cent — using a stick, a well and some arithmetic.

18 centuries

Roughly how long educated Europeans had accepted a spherical Earth before Columbus was even born.

25% too small

How badly Columbus underestimated the size of the planet, after mixing up Arabic miles with the shorter Roman mile.

~20,000 km

The true distance from the Canary Islands to Japan. Columbus told his investors it was roughly 5,000.

1828

The year a popular novelist published the biography that invented the flat-Earth confrontation. Columbus had been dead for 322 years.

1961

As late as this year, the Encyclopædia Britannica was still telling readers Columbus had proved the world was round.

You know this one. It gets told to children with the same easy confidence as a fact about gravity.

Columbus, a lone visionary, knew the Earth was round. Everyone else — kings, bishops, scholars, the lot — thought it was flat: a great disc with an edge you could tumble off. His own sailors grew terrified as the voyage dragged on, certain the ships were about to slide over the rim of the world into nothing. Columbus pressed west anyway, found land, and proved the doubters wrong. Reason beats superstition. The lone genius is vindicated. Roll credits.

It is a wonderful story. A hero, a crowd of fools, a tidy moral. And it falls apart the instant you ask the most basic question available: did educated Europeans in 1492 actually believe the world was flat?

They did not. They knew full well it was round — and had known for the better part of two thousand years.

The round Earth was not a fifteenth-century discovery. It was old news. Ancient news.

The Greeks had it sorted by at least the sixth century BC. Pythagoras usually gets the credit, with Aristotle, Euclid and Aristarchus signing on after him. And Aristotle did not merely assert it — he gave reasons. The curved shadow the Earth throws across the Moon during an eclipse. The way the visible stars shift as you travel north or south. Then, in the third century BC, a scholar named Eratosthenes did something genuinely extraordinary. He measured it.

He knew that on the summer solstice the noon sun shone straight down a well in Syene, while at the very same moment, up in Alexandria, it cast a clear shadow. From the angle of that shadow and the distance between the two cities, he worked out the circumference of the entire planet. His answer was off by only a few per cent. A man with a stick and some arithmetic had sized the Earth — and very nearly nailed it — seventeen centuries before Columbus was born.

Here is the part the story always skips: that knowledge never went away. It was not lost in some long medieval blackout. Medieval universities taught the spherical Earth as standard fare — one of the most popular textbooks of the age, Sacrobosco’s On the Sphere, is literally a book about it. The Church had accepted a round Earth for centuries. Dante built the whole architecture of his Inferno around a spherical world. Even ordinary sailors knew, because every sailor had watched a ship vanish over the horizon hull-first and mast last — which is not a thing that happens on a flat sea.

The historian Jeffrey Burton Russell once spent an entire book dismantling the flat-Earth myth, and his conclusion was about as blunt as historians ever get: with a tiny handful of eccentric exceptions, no educated person in the whole history of Western civilisation, going right back to the third century BC, ever believed the Earth was flat.

So if every scholar Columbus would ever have to face already knew the Earth was round, then the famous showdown — lone visionary against a mob of flat-Earthers — simply could not have happened. There were no flat-Earthers in the room. Which leaves a rather large question hanging. What were they all arguing about?

Columbus never had to convince anyone the Earth was round. His opponents knew that as well as he did. They also knew how big it was — and that was the real problem.

The real fight was never about the shape of the planet. It was about the size of it. And on that question — the part that somehow never reaches the children’s version — Columbus was wrong, and the experts he is remembered for humiliating were right.

Eratosthenes, remember, had the Earth’s circumference roughly correct. That was deeply inconvenient for Columbus, because a correctly sized Earth made his plan impossible: the open ocean between Europe and Asia would be far too wide for any ship to cross. So Columbus went looking for smaller numbers, and he found some. He leaned heavily on a ninth-century Persian astronomer, al-Farghani — Latinised to Alfraganus — who had measured the length of one degree of the Earth’s surface, and measured it well.

The trouble was the units. Al-Farghani had done his sums in Arabic miles, each a little over 1,800 metres. Columbus assumed he meant the shorter Roman mile of around 1,480 metres. That single careless assumption shrank the entire planet by roughly a quarter.

Then he made it worse. He adopted an old and already-rejected estimate that stretched the landmass of Europe and Asia across 225 degrees of the globe instead of the accepted 180, padded it further with Marco Polo’s travels and a generous guess at where Japan sat, and arrived at a very happy conclusion: Asia was a quick hop west. He told his backers Japan lay some 5,000 kilometres beyond the Canary Islands. The true figure is closer to 20,000.

Some historians think this was not a blunder at all — that Columbus, a salesman assembling a pitch, simply reached for the smallest numbers he could find and then stopped looking. The naval historian Samuel Eliot Morison put it neatly: Columbus’s reasoning ran backwards. He was certain he could make the voyage, so the figures were quietly made to agree. Honest error or motivated arithmetic, it came to the same thing. The maths was a wreck.

And the experts could see it.

Around 1484, Columbus pitched the voyage to King John II of Portugal, whose panel of geographers turned him down flat. Their objection: his distance to Asia was about four times too short. They were correct. He took the plan to Spain, where another commission examined it and reported back to Queen Isabella that Columbus had badly underestimated the distance, and that the venture was impractical.

These were not snarling bigots waving Bibles. They were competent geographers doing arithmetic — and the arithmetic told them, accurately, that no ship of the 1490s could carry enough food and water to cross that much open sea. They were not the fools of the story. They were the careful ones.

They were also, on the merits, completely right. If the Atlantic had been nothing but open water all the way to Asia — which, in terms of raw distance, it is — Columbus and every man with him would have died of thirst somewhere in the empty middle. The ocean really was too wide.

What saved him was the one thing nobody’s calculations had accounted for, because nobody in Europe knew it was there: an entire pair of continents, sitting almost exactly where Columbus had promised Japan would be. He did not out-think the experts. He ran out of ocean at the luckiest possible moment. His crew did grow restless near the end of the crossing — that part is true — but not because they feared the edge of the world. They were running low on supplies. Which was, of course, precisely what the experts had warned about.

Columbus made landfall, decided he had reached the fringes of Asia, and went to his grave still insisting on it. He never knew he had found anything new at all.

He was rescued by the one thing his calculations had no idea existed: two enormous continents, parked exactly where he had told his investors they would find Japan.

So if the heroic flat-Earth confrontation never happened — where did it come from?

Mostly from one man. And he was not a historian. He wrote ghost stories.

Washington Irving is the reason American children grow up knowing Rip Van Winkle and The Legend of Sleepy Hollow. In 1828 he also published a four-volume biography, A History of the Life and Voyages of Christopher Columbus. He had travelled to Spain meaning only to translate some documents, got more ambitious, and wrote the whole life instead. And being a storyteller to his bones, he staged a scene: Columbus standing before a council of churchmen at Salamanca, defending the round Earth while ignorant clerics hurled scripture at him.

It is vivid. It is stirring. It is also more or less invented. There was a real commission, and it did examine Columbus’s proposal — but its genuine objection, the one that actually mattered, was the distance, not the shape of the planet. Irving took a dry committee meeting about a sailing route and rewrote it as a clash between enlightenment and superstition, because that made a far better chapter.

Readers swallowed it whole, partly because the book looked like serious scholarship rather than the half-fiction it really was. Then others piled on. In 1834 a French scholar, Antoine-Jean Letronne, recast the medieval Church as a nest of flat-Earth believers. Decades later, John William Draper and Andrew Dickson White — White was the founding president of Cornell University — folded the whole thing into a sweeping story of science forever at war with religion. By the late nineteenth century it was simply in the textbooks. An American schoolbook from 1919 told children, as plain fact, that in Columbus’s day people believed the Earth was flat and the ocean full of monsters. The Encyclopædia Britannica was still repeating a version of it as late as 1961.

A short-story writer invented a scene. An anti-clerical academic generalised it. Two more men hardened it into a worldview. The schools finished the job. Four men and a century or so — and an event that never took place became something nearly everyone now “knows.”

The myth survived for the most human reason there is: it was flattering.

It made the modern world look clever and the past look like a room full of idiots — and there is almost nothing people enjoy more than feeling superior to their ancestors. It handed the comforting tale of progress-over-superstition a perfect mascot. And the true version is so much less satisfying. A gifted sailor who was also a sloppy mathematician, rescued from a fatal miscalculation by sheer dumb geographical luck, while the so-called fools who doubted him turn out to have been the careful, competent, correct ones. There is no clean hero in that. So it lost.

The uncomfortable bit is the last bit. You were not taught the wrong story because someone checked the facts and decided to lie. You were taught it because, for the better part of two hundred years, the story was simply too good for anyone to bother checking. It got repeated until repetition did the work of evidence.

Which is worth sitting with for a moment — because it raises a quiet little question about everything else you were taught, and have never once thought to question since.

A round Earth that every educated person already knew about. A size calculation that was off by a continent. A panel of experts who were right and got remembered as fools. And a heroic showdown that a novelist simply made up, three centuries after the man himself was dead.

Columbus didn’t set out to prove the world was round. He set out to prove it was small. He was wrong — and a hemisphere he didn’t know existed reached up and saved his life.

OneWildWorld!

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SOURCES

Jeffrey Burton Russell — “Inventing the Flat Earth: Columbus and Modern Historians” (1991) — the definitive scholarly debunking of the flat-Earth myth.

Washington Irving — “A History of the Life and Voyages of Christopher Columbus” (1828) — the four-volume biography that staged the fictional Salamanca confrontation.

Eratosthenes’ measurement of the Earth’s circumference, c. 240 BC — as preserved in the account of Cleomedes.

“Voyages of Christopher Columbus” and “Myth of the Flat Earth” — encyclopaedic surveys of the size dispute, the al-Farghani units error, and the Marinus of Tyre landmass figure.

Douglas McCormick — “Columbus’s Geographical Miscalculations”, IEEE Spectrum — the Roman-versus-Arabic-mile error and the 25% / distance miscalculation.

Samuel Eliot Morison — “Admiral of the Ocean Sea: A Life of Christopher Columbus” (1942) — on Columbus’s navigation and his selective use of figures.

John William Draper — “History of the Conflict between Religion and Science” (1874); Andrew Dickson White — “A History of the Warfare of Science with Theology in Christendom” (1896) — the works that hardened the myth into the science-versus-religion narrative.

Antoine-Jean Letronne — “On the Cosmographical Ideas of the Church Fathers” (1834).

Encyclopædia Britannica, 1961 edition — cited as a late example of the myth surviving inside a major reference work.

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