In first grade, we are all taught how to read clocks. That unit also covered the general fact that 60 seconds are in one minute, and 60 minutes are in one hour. Move on to 5th grade, and we learn that all equilateral triangles have 60 degree angles. Just one year later, in 6th grade geography class, you learn that geographic coordinates go by 60. 60, another 60, and more 60s. But why this specific number? In this article, I will be explaining the history behind 60 and why it is used so often as a base in measurements. On we go, to the history and usefulness of the number 60!
Our first stop will be with the Babylonians, who used a counting system called the sexagesimal system for mathematics and astronomy. Just like how the metric system multiplies by 10, this system counts by 60s. Just like a ‘base 10’, this system uses a ‘base 60’. This is because 60 is a highly composite number (it has many factors) and one of these factors is 12. We usually count to 10, using our fingers, but the Babylonians counted to twelve using the three joints found on every finger, but just for 4 fingers (because 4 fingers times 3 joints per finger equals 12). The Babylonians adopted this system from the Sumerians, who were using it as early as 3500 BC. They used it for everything, even currency. Just like how one dollar is worth 100 pennies, one golden mina was worth 60 silver shekels. Slowly, this system started gaining popularity throughout the world, and at one point, everyone from the Ancient Chinese to Ptolemy was using it for everything from time, to calendars, fractions, currency, angles, and even astronomy.
Nowadays, even though most people use the U.S. customary system and the metric system, the sexagesimal system has been ingrained into our culture. We use it to measure angles, geographic coordinates, electronic navigation, and time. As we have all learned, the most common unit of angular measure is the degree. In a circle, there are 360 degrees, six sixties. Even if we’ve never known about it, the sexagesimal system is not just helpful, but also a vital part of modern mathematics
In a nutshell, it isn’t by coincidence that the number 60 is found in all types of measurements like time and coordinates. It’s based on something much bigger and much more ancient than that. The sexagesimal system, an idea that has endured for over 4000 years, is the reason why everything works the way it does. And although it doesn’t seem to play a prominent role in our lives, it is the power behind the gears and motors that churn behind all of reality. It is what makes us who we are. It is the number 60.