The origins of Pi are as ancient and mysterious as the number itself.
The concept of Pi, or the mathematical value of the the circumference of a circle, has been around for thousands of years. The problem was, no one knew how to refer to it. Not until William Jones came along, that is.
Let us introduce you to a New Introduction of Mathematics:
In 1706, a British mathematician named William Jones with a fascination with the Orient chose to use ∏, the Greek symbol for Pi, to represent the equation in his text, Synopsis Palmariorum Matheseos.
And, thanks to digital imaging, Google’s generosity, and the Internet Archive Project, you, too, can read page 253 of William Jones’ text, and the first use of Pi.