This Pi Day, remember William Shanks

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Today is a special Pi Day as 3/14/16 is a good approximation to the value of pi, 3.14159265…. It’s a day for math geeks and for people who like pies to make puns. But today I ask you to remember William Shanks. When I was younger – probably in my early teens – I read about William Shanks and his calculation of pi in a book on mathematics. (I was one of those kinds of kids.) The basics of the story stuck with me, but I did forget his name. One night in college, I was bored of studying my physics when I remembered this story. This was in the days before Wikipedia, so I had to go to the campus library and find a book on the history of pi. After some searching, I found the story of William Shanks. To make sure I never forgot his name, I wrote it on a piece of paper and taped it to the back of my graphing calculator. A year or so later, my “William Shanks” calculator died and I bought a new one. I still have, though rarely have reason to use, my “William Shanks Jr.” calculator. So who was the real William Shanks? He was a Nineteenth Century amateur mathematician. (They didn’t have Netflix or Xbox back then.) His hobby was calculating various mathematical constants. There are various formulas for calculating pi, and he would slowly work out the next digit by hand. When he died in 1882, he had calculated the first 707 places of pi, which was the record until the 1940s. The reason I remembered his story, is that poor William Shanks made an error in his calculations at the 527th place. Who knows how many hours he spent filling page after page with calculations that were, to be frank, utterly worthless. I see William Shanks as a cautionary tale to double, triple, even quadruple check your work.