ELI5: Explain Like I'm 5

Harmony of the spheres

The idea of the harmony of the spheres goes back a very long time - thousands of years, in fact. People have always been fascinated by the stars and the movements of the planets, and in ancient times they believed that these celestial bodies moved in perfect, harmonious motions.

Imagine you have a bunch of musical instruments - like a drum, a guitar, a trumpet, and so on. Each of these instruments makes a particular sound or pitch when you play it. Now, if you were to play all these instruments together in a certain way, you could create a beautiful, harmonious sound. You might have heard this before if you've ever listened to a band play music.

Now, imagine that instead of musical instruments, you had the planets - the Sun, the Moon, Mercury, Venus, Mars, Jupiter, and Saturn. Just like musical instruments, these planets each have their own unique properties and movements. And just like with musical instruments, people believed that the movements of these planets had to be in a certain way in order to create a beautiful, harmonious sound.

This idea of the harmony of the spheres became very popular among ancient philosophers and scientists, who believed that the movements of the planets were not random but were instead part of a grand, cosmic pattern. They believed that this pattern was perfect and beautiful, and that it was evidence of an intelligent, divine force at work in the universe.

In later years, people began to realize that the idea of the harmony of the spheres was not entirely accurate. They discovered that the movements of the planets were not always perfect or predictable, and that there were other factors at work that could affect their motions. However, the idea of the harmony of the spheres still holds a certain appeal, as it reminds us that there is something grand and mysterious about the universe and our place in it.