Infinity (∞)
1655 CE
The Lemniscate, a Ribbon Without Ends
The familiar infinity symbol is called a lemniscate, from a Latin word for ribbon. It looks like a looped strip laid on its side, a path that curves back into itself without a clear beginning or end. As a mathematical symbol, ∞ was introduced by John Wallis in the mid seventeenth century and quickly became part of the language of calculus and analysis.
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The familiar infinity symbol is called a , from a Latin word for ribbon. It looks like a looped strip laid on its side, a path that curves back into itself without a clear beginning or end. As a mathematical symbol, ∞ was introduced by John Wallis in the mid seventeenth century and quickly became part of the language of calculus and analysis.
On the page, ∞ stands in for without bound. In a limit, it marks a variable that grows beyond any fixed number. In an integral, it can describe an area that stretches forever. The symbol does not claim that infinity is a normal number we can reach. It is a compact way to say that the process keeps going, that there is always more.