Nicolaus Copernicus (1473-1543) was a Polish multi-talent and one of the greatest geniuses of the Medieval era. He made significant contributions in many areas, but the most famous bears his name: The Copernican Revolution. He placed the sun at the center of the universe rather than the Earth.
Quantitative Theory of Money
Several hundred years had elapsed since Fibonacci had introduced the Hindu-Arabic numerals into Europe, and they were influencing almost every corner of academia. Copernicus used them to formulate a new theory of money. He postulated that the more money is printed and circulated in the economy, the higher the prices of goods and services.
Prices are determined by the amount (quantity) of money in circulation. In modern language, this is now known as the quantitative theory of money and is still one of the cornerstones of economics.
However, ancient astronomers had for a long time known that some planets sometimes moved in the opposite direction in the sky, called retrograde motion. Influenced by the Platonic ideals, Ptolemy postulated that this could be explained by circles within circles. He called them epicycles.
Today, we have a mathematical tool called Fourier transformation, that teaches us that it is possible to split any repeating signal into sums of circles of different speeds. Therefore, the Ptolemaic model turned out to be surprisingly good at predicting the motions of the planets, even if it was not physically correct.
To achieve an accurate result, astronomers needed dozens, even hundreds of different epicycles. Copernicus thought that this was a sign that something was wrong. He had been influenced by the Aristotelian notion that the world needed to be studied in its own respect and not assumed to be a mere shadow of some Platonic ideal in idea heaven.
He instead postulated the far simpler model that both the Earth and the planets were revolving in simple circles around the sun. The outer planets (Mars, Saturn, and Jupiter) would then automatically show retrograde motion in the sky.
Others noted that many of the people who liked Copernicus’ model had a different Christian faith and were labeled heretics by the Catholic church. Therefore, what was a purely scientific question became politicized. Many people refused to accept the Copernican model because the “wrong” people promoted it.
In the end, Copernicus’s ideas won and laid the foundation for future giants of science like Johannes Kepler, Galileo Galilei, and Isaac Newton.