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# How to Add and Subtract Like an Egyptian

What do drawings of ropes, fingers, and flowers have to do with math? Keep on reading to learn how the ancient Egyptians used these and many other hieroglyphs to count numbers!

By
Jason Marshall, PhD,
February 26, 2016
Episode #138

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## The Birth of Arithmetic

Nobody knows precisely when our story begins, but we know that for some reason around 30,000 years ago people started making tiny notches in bones. Researchers who found these bones have speculated that the marks carved in them were probably used to keep track of things like the number of sheep in a field or the number of days since the last harvest. In other words, these so called “tally-bones” represent the origin of counting.

But this system for keeping track of numbers isn’t so great (which is why we aren’t all using it!). Why do I say that? Well, imagine you’re an ancient tally-bone carver and your job is to make one notch on your bone for every full moon since the last harvest. After four full moons, your bone has four notches:

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Which, perhaps, means that it’s time to plant your crops again and restart your tallying. For this purpose the system seems to work pretty well. But what if your job was to keep track of the number of weeks that have passed instead of the number of months? After those same four months, your tally-bone would contain a lot of notches—almost 20 of them:

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All of those notches means that it’s a lot tougher to tell at a glance how long it’s been since the harvest. Even worse, what if your job is actually to keep track of the number of days that have passed. Then your tally-bone would contain over 100 notches:

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What a mess! Even if you don’t run out of room on your tally-bone, every time you want to know how many days have passed you have to start from the beginning and count each and every mark. That’s obviously not too smart…which led people to start looking for a better way to do things.