If there is one analogy I regularly come across in personal development literature that is certain to make me breathe a sigh every single time, it is when I read the statement that not long ago, people used to believe the Earth was flat. It is, of course, meant to illustrate what we mean by a paradigm shift. However, I am usually amazed that such people appear to be so ignorant of the facts that surround the matter.
The misconception that educated people at the time of Columbus believed in a flat Earth, and that his voyages refuted that belief, has been referred to as “The Myth of the Flat Earth“. In 1945, it was listed by the Historical Association (of Britain) as the second of 20 in a pamphlet on common errors in history. – Wikipedia
By the way, if you do want to illustrate a real paradigm shift, then the movement away from an Earth-centric view of the planetary system to a heliocentric view as proposed by Copernicus provides us with a much better example.
In the above video, Carl Sagan explains beautifully how Eratosthenes not only figured out that the world was actually round but also, working from observation actually calculated what its circumference would be; and he did all of that in the third century BC.
Of course, in ancient Egypt, they did not measure distance in metres and kilometres. The actual unit Eratosthenes used was the stadium, so his calculation of the Earth’s circumference is expressed in stadia.
He had the distance between Alexandria and Swenet (Aswan) measured as being 5,000 stadia and calculated the Earth’s circumference as 252,000 stadia which works out to 39,690 Km provided the stadium he used in the calculation was the Egyptian standard (157.5 m). Astonishingly, that would represent an error of less than 2%.
Whilst the notion of a flat Earth did persist in some parts of the world (notably, China) until quite late, the idea that the Earth was spherical was, in fact, proposed as early as the 6th century BC by Pythagoras. Perhaps it’s time for a paradigm shift in our view of just what our ancient ancestors were capable of understanding 😉