Roman, Arabic, and…Cistercian?
We’ve all seen Roman Numerals. For some reason, I was taught those letters at some point in grade school. The odd thing is, none of my teachers ever taught me to add or subtract in that format. How about multiplication or division? If you ever tried it, you know that Roman Numerals do not lend themselves to such tasks.
The number system we use is typically called the Arabic System. It includes a zero, and we can manipulate the numbers with ease. I’ll bet that it has never occurred to anyone reading this essay to try to do any math with Roman Numerals. We can all agree that the approach we use is far superior.
During the Middle Ages, the Arabic System competed with Roman Numerals for dominance. Roman Numerals are fine if you are writing dates or numbering the pages in a preface; other than that, they have little utility.
*****
Piper Pandora Pennington descended her attic room’s steps and landed outside the bedroom of her six-year-old sister, Susie. She took a quick peek inside before she determined her next course of action. She quickly decided that she needed to get to the kitchen for a bottled water and an apple before tackling the strange site in her sister’s room.
One quick trip later, Piper landed back at her sister’s door.
“Permission to enter, please.”
“Pi!.” Susie picked up Melvin, the stuffed octopus, and moved him side to side in a fit of excitement.
“Melvin, should we let Pi in?”
A muffled, poorly disguised voice said, “Sure, that sounds fine.”
At that moment, Dogzilla started a wrestling match with Pi’s left foot. Before she could stop him, Dogzilla had removed her sock and was doing his best to eat it.
“Hey, stop that. Dogzilla…No!”
He ignored her and kept at the sock. He paused when Susie tapped her blackboard with a piece of chalk and announced, “Attention! Attention! Class come to order!”
Dogzilla, as if on cue, dropped the sock and sat down on the floor beside Melvin. Piper found a place on the floor and waited with anticipation.
“Ok, class. Today we will learn about a numbering system, and it’s not Roman Numerals or the Arabic one. It is something different, and it is very cool.”
Piper got curious. She knew nothing about another number system; she had never thought about it. As she pondered this mystery, it occurred to her that Susie was capable of acting twenty years older than she actually was at times. Most times, she was simply a six-year-old girl, but this was not one of them.
*****
During the Middle Ages, there was another, competing number system; a system few have ever heard of. I just recently learned of its existence; it never came up when I was getting a graduate degree in the history of science at Harvard. Nor did it turn up in any history of mathematics classes I have taken since I left Cambridge. I was surprised when I recently came across The Cistercian System. It is a bit odd and just as useless as Roman Numerals when it comes to manipulating numbers, but it has its charms.
*****
Susie took her piece of Hagoromo chalk and started drawing on the board. Piper and Melvin sat at strict attention as Dogzilla sprinted to attack Susie’s foot.
“Ouch! Dogzilla, stop it. We can play in a little bit, but first, you need to hear this.”
Piper grabbed the furball and held him as Susie regained her composure. Susie turned and drew a beautiful figure.
“That class…is 5863.”
Piper turned her head slightly to the left. “Really, little sis? I have never seen that before.”
“Yep, I saw it on a video, and I knew I better tell everyone.”
“Can you write out some more numbers?”
“Sure can Piper-o.”
Susie turned fully around in an attempt to disguise the drawing until it was done. After a few moments, she turned and struck a pose.
“Ta-dah!”
“What is that one?” said Piper as she narrowed her eyes and concentrated.
“Mmmm…1234.”
“You mean one thousand two hundred and thirty-four?”
“Yep.”
As Piper studied the drawing, she heard a buzz coming from the black box on Susie’s wall. Karen, the girl’s stepmother, had hit the call button on the Raspberry Pi controlled intercom and said, “Susie, are you there?”
“Yep!”
“Susie, Mama Rose, and Papa Joey say they need your help with something. They want you to go over there right now.”
Susie, feigning surprise, hit a dramatic pose, leaned in, pressed the button on the wall, and said, “Yep.”
Susie grabbed Melvin and ran into Piper’s arms. “Gotta go, sister-o.”
Piper kissed the top of her head and sent her on her way. As she watched Susie and Melvin bound down the stairs, Pi was ambushed by Dogzilla, who was hiding under a dresser. Piper picked him up and took the furball to her room, where they both were going to research this strange and mysterious Cistercian Number System.
*****
Who were The Cistercians? You have probably heard of the Benedictine Monks; they are a well-known order of the Catholic Church. The Cistercians are an offshoot of the Benedictines. Basically, they thought that the Benedictines partied too much. They weren’t quite aesthetic enough, or sufficiently fundamentalist, for the Cistercian’s tastes. There are very few of them to be found nowadays, but they are not extinct. Of course, they left behind this interesting and obscure numbering system. Not a bad legacy.
*****
Piper placed Dogzilla on the floor. She took a few chew toys off her desk and tossed them across the room. She almost smiled as she watched Dogzilla attack the bone and rope.
“Alright, let’s get to work,” she said to no one.
She typed “Cistercian Numbering System” into Google and sat back as the results quickly populated her screen.
“Hmmm, I’ll be. See that, Dogzilla? There is such a thing. Who knew?”
She looked at Dogzilla rolling on the floor with the rope, oblivious to the conversation she was trying to have with him.
“Well, I can see you are not going to be of much help.”
She read all there was to read about the numbering system. Within about 30 seconds, she had a complete understanding of how it works. It took her another second to dismiss the system as useless for her needs. Still, she took a little more time to look at the construction of the numbers. Really cool.
*****
The Cistercian System is best learned by studying examples of the numbers. It is unnecessary to get into the mechanics of how the system works; there is not much to be discovered from that. For instance, the system will not allow any number larger than 9999. Like the Roman System, it makes no sense to try to add or subtract Cistercian Numbers. About the only thing they are suitable for is numbering pages and writing dates.
I decided to write a post about these numbers because I was surprised to learn about them. I don’t know how they have spent all this time eluding me. I spent many years studying medieval science and mathematics, and I don’t understand how I missed this number system. It doesn’t make any sense.
I will end this post with a few more examples of numbers written in Cistercian form. Why? Piper Pandora Pennington and her sister, Susie, are right. These numbers look really cool.
4892 5555 8321 6751
