Introduction#
Some things become so familiar that we stop noticing them.
The symbols +, −, ×, and ÷ are among them.
We learn them in elementary school and use them almost every day. Yet few of us ever stop to ask: Why do these symbols look the way they do? Who invented them?
It is easy to assume they were created together as part of a complete mathematical system.
The real story is far more surprising.
These four symbols were born in different centuries, created by different people, and emerged from entirely different circumstances. Some grew out of commerce, some from scholarly debate, and one did not even begin its life as a mathematical symbol.
So how did people calculate before these symbols existed? And how did a handful of simple marks become an essential part of mathematics—and eventually modern science itself?
In this episode, we travel back through history to uncover the remarkable stories behind the symbols we use every day.
Why Explore This Topic?#
Symbols are everywhere.
Mathematical notation, written language, maps, musical scores, traffic signs—they have become such a natural part of daily life that we rarely think of them as inventions.
Yet every new system of representation changes more than the way we write.
It changes how information is recorded, how knowledge is shared, and even how people think.
Mathematical symbols are a perfect example.
The familiar symbols +, −, ×, and ÷ are much more than convenient shortcuts for calculation. They helped mathematics move beyond lengthy verbal descriptions and become a language that is clearer, more precise, and easier to communicate.
Understanding where these symbols came from is not simply about tracing their origins.
It is about asking why seemingly small changes can reshape an entire field of knowledge—and sometimes even influence the course of civilization.
What We’ll Explore#
In this episode, we’ll explore questions such as:
- Why did ancient mathematics have no familiar arithmetic symbols?
- Where did the plus and minus signs come from?
- Why were there once several competing symbols for multiplication?
- Why is the division symbol still not used universally today?
- How did a few seemingly simple symbols influence mathematics, science, and even modern computing?
References#
If you’d like to explore these topics further, here are the primary sources referenced in this episode.
Historical Sources#
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British Museum. Rhind Mathematical Papyrus
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William Oughtred. Clavis Mathematicae (1631)
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Johann Heinrich Rahn. Teutsche Algebra (1659)
Academic Papers#
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Monash University. Re-examining Problems Nos. 49–52 of the Rhind Mathematical Papyrus
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University of Oxford. A History and Philosophy of Algebra in Islamic Mathematics with a Focus on the Solution of the Polynomial
Books#
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Florian Cajori. A History of Mathematical Notations
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Alfred North Whitehead. An Introduction to Mathematics
Organizations & Standards#
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Mathematical Association of America (MAA), Convergence: History of Mathematics
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International Commission on the History of Mathematics (ICHM)
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ISO 80000-2. Quantities and Units — Part 2: Mathematics