Today, 3/14, is my favourite unofficial holiday: Pi Day, the day to celebrate the circle. Today we make pi jokes, eat circular foods, and recite as many digits of pi as we can recall.

I’ve had a fondness for π since I learnt about it in high school math. It’s a number that is unknown, yet a constant that’s essential. I’m always on the lookout for pi references (an elusive search). Here’s a quote I love:

**…an expansion of pi to only forty-seven decimal places would be sufficiently precise to inscribe a circle around the visible universe that doesn’t deviate from perfect circularity by more than the distance across a single proton.**

**-Richard Preston, The Mountains of pi, The New Yorker, March 2, 1992**

So, have a happy day today, eat something round, and give a mathematician a hug.

- Q:What do you get when you take the sun and divide its circumference by its diameter?
- A: Pi in the sky. (From http://www.mahalo.com/pi-jokes)

Happy belated Pi Day to you to Elizabeth Ann! What kind of pie did you indulge in? Was it homemade? What do you do to celebrate Pi Approximation Day on July 22 (or do you recognize that as a Pi related holiday)?

Laurie