Good Math

History

As major mathematical constants go, e has less history to it than most. It’s a comparatively recent discovery.

The first reference to it was by the English mathematician William Oughtred (1575–1660) during the seventeenth century. Oughtred is the guy who invented the slide rule, which works on logarithmic principles. The moment you start looking at logarithms, you’ll start seeing e. Oughtred didn’t actually name it, or even really work out its value, but he did write the first table of the values of the natural logarithm.

Not too much later, it showed up in the work of Gottfried Leibniz (1646–1716). Leibniz’s discovery of the number wasn’t too surprising, given that Leibniz was in the process of working out the basics of differential ...