Christopher Colombus
A visionnary genius? Really?
In elementary school, I learned that Christopher Columbus was the only man in his time to believe that the Earth was round. This is why he wanted to sail westwards to India, to prove everyone wrong. People would tell him “You’re crazy! You’re going to reach the edge of the flat Earth!", and he would answer “Of course not, the Earth is round!". So in a way, he is painted to be this visionary genius who made it possible for Europeans to arrive on a new continent.
So that’s what I learned in school. But what really happened?
Actually, back when Christopher Columbus was alive, it was generally accepted that the Earth is round. And that had been the case for centuries, since the Antiquity.
In ancient Grece, Eratosthenes had even computed the circumference of the Earth by measuring the size of shadows in several locations. His estimated value for the radius of the Earth was fairly close to the actual value. Because of all the hypotheses he had to make, there was a bit of pure chance involved for him to be so close to the right value, but in any case, Eratosthenes’ method was known in the 15th century.
And Eratosthenes wasn’t the only one to have tried to measure the circumference of the Earth. Several other astronomers did too, with varying results: some found a circumference that was a bit bigger, some found a circumference that was a bit smaller. Most people agreed that the exact value had to be somewhere in the middle of all these estimates. And they were correct in thinking so.
Rather than use an estimate close to the accepted value for the circumference of the Earth, Christopher Columbus used the estimate made by another ancient Greek named Posidonios. He chose this value because it was the smallest estimate of them all, making it seem feasible to sail westward to India.
So if people told him he was reckless, it wasn’t because they thought the Earth was flat, it was because they thought he was seriously underestimating the circumference of the Earth.
Moreover, he only took enough ration to survive the estimated duration of the trip. But Asia was much further west than what he had estimated. So if the American continent hadn’t been there, Christopher Columbus and his men most likely would have died at sea. All in all, he was completely off the mark and got very lucky.
