The search for ideal numerical relationships that could be applied to everyday life had already begun in ancient Greece with Pythagoras and Euclid and was subsequently carried on by characters like Leonardo Fibonacci, Leonardo da Vinci and Johannes Kepler. The Sectio Aurea, or ‘Golden Section’, which relates a smaller part to a larger part and the larger part to the whole, was explored in music as well. Indeed, during the Middle Ages, music formed—along with arithmetic, geometry and astronomy—the so-called Quadrivium, the whole of the human scientific knowledge. Therefore, it is easy to understand why the application of scientific theories to music was considered a natural process.
More information: Antonio Stradivari Set 1, Volume 3, Page 124