Make Your Own Pythagorean Cup

My parents recently went to Greece. They brought me back a souvenir—a practical joke cup called a “Pythagorean cup.” The legend behind the cup is that Pythagoras or one of the Pythagoreans invented this cup to prevent gluttony. The vessel looks like a cup with an odd pillar in the center. When you fill it…

Card Table Proof of the Pythagorean Theorem

We own a standard card table that we leave tucked away in the basement until the kids want to have a lemonade stand on the front sidewalk or we need the extra table space for a large Thanksgiving dinner. It is the standard kind with legs that fold underneath it so it is easy to store….

Editing mathematical writing

As I mentioned in a previous post, I’ve been assigning large-scale collaborative writing projects in my mathematics classes. I’ve had my topology students write a textbook for their class, and this semester I’ve been doing the same in my discrete mathematics class. As I mentioned in that post, the approach has been very successful, but…

Mathematics in Moby-Dick

Twice before I have posted mathematical passages that I have stumbled upon in works of literature. Yesterday I finished reading Moby-Dick (great book, great ending!), so I thought I’d highlight a few mathematical passages that it contains. Especially interesting to me is the second one in which Melville mentions the impossibility of squaring a circle….

Catching up on some reading: Dyson’s birds and frogs

The semester’s over and I’ve been cleaning off my desk. I found an old issue of the Notices of the AMS (February 2009) with a bookmark in it. It was Freeman Dyson‘s Einstein Lecture entitled “Birds and Frogs.” Here are some good quotes from it. He opens with: Some mathematicians are birds, others are frogs….

Mathematics in novels and Martin Gardner RIP

I always enjoy encountering mathematics in non-mathematical works of fiction. (I posted excerpts from Candide and The Brothers Karamazov last fall.) Here are a few more that I came across recently. The first is in Dashiell Hammett’s 1934 murder mystery The Thin Man. Here is a conversation between private eye Nick Charles and his wife Nora at the…

Using wikis in mathematics classes

Wikipedia describes a wiki as a website that allows the easy creation and editing of any number of interlinked web pages… [Wikis] are often used to create collaborative websites, to power community websites, for personal note taking, in corporate intranets, and in knowledge management systems. I have used wikis in three of my classes: two…

Steven Strogatz writes about the elements of mathematics in the NY Times

Yesterday the mathematician Steven Stragatz wrote the first article in a mulit-part series for the NY Times. In this first article, called From Fish to Infinity, he describes his intent. Crazy as it sounds, over the next several weeks… I’ll be writing about the elements of mathematics, from pre-school to grad school, for anyone out…

Math in literature

I’ve been reading some classic literature lately and was interested to see mathematics show up two of these works. Last week I read Voltaire’s Candide (1759). One of the main characters is the ridiculous Dr. Pangloss, who subscribes to Leibniz’s philosophy of optimism (or Voltaire’s take on optimism). Leibniz believed in a good and omnipotent…

Kindergarten Mathematics (part 2): a report

Last week I wrote a blog post asking for suggestions for math to present to my son’s kindergarten class. My readers posted many great comments. Thank you all. Today was the big day,… and it was a great success! I began by talking about what I do. My son introduced me as a math teacher….