Apparently, it's the 40th anniversary of the invention of the famous puzzle. It was developed by the Hungarian architecture professor in 1974 as an exercise to teach his students how to solve problems in three-dimensional geometry. It of course became immensely popular; the most popular puzzle ever sold. This was according to NBC News, which ran a story about the cube this evening. The NY Times had an article a couple of days ago about the anniversary, which is being observed by a science museum in New Jersey. Their exhibit includes a solid gold cube with gemstone faces, said to be worth $2.5 million.

I remember my first experience with the cube. I was a junior in college, and I was at a party for math majors hosted by one of the professors. I noticed a cube on a bookshelf. I picked it up and asked what it was. Someone behind me joked "he asks what it is, innocently!" I was impressed that you could turn the sides without it falling apart, but I was told that was not what was interesting about it--it was a puzzle, a fiendish one. I had to order one of my own. This was before the fad hit the U.S., before a major toy company had picked the puzzle up; my copy was a rather roughly-made version by a little company in Virginia called Logical Games. It was made of a white plastic, unlike the mass-market ones that soon appeared that were made of black plastic. As soon as I got it, I worked hard to solve it, spending a half hour or more a day. I got a hint or two from friends, but it was a source of great pride when I finally solved it after five weeks. After solving it, I still couldn't put it down; I worked to improve my algorithm, and I spent many hours figuring out how to put the cube into pretty patterns (checkerboards, etc).

In my senior year, the Rubik's fad hit with full force. A bunch of us gathered in from of a television to watch NBC News do a story about the puzzle featuring one of our professors (Joe Buhler) juggling three cubes, while explaining how he uses it to teach abstract algebra. I was charmed to see the beginning of that story (which aired in 1981) in this evening's report, although they didn't show the bit with Prof. Buhler.

It's been a while since I've played with a Rubik's cube. The original white-plastic cube now sits on a bookshelf in my office at school, along with a variety of other Rubik's type puzzles. These include a 4 by 4 by 4 cube (Rubik's Revenge), and a 5 by 5 by 5 cube. The latter I got in Berkeley at the 1986 International Congress of Mathematicians, which I attended right after finishing my PhD at Oregon. A fellow was selling them at the exhibits area of the conference; he said they were actually prototypes. The toy company had decided not to market them, and he had purchased the molds and a few hundred copies of the prototype. He also sold me a dodecahedron (twelve sides, each pentagonal), also prototypes that wouldn't be marketed. (The dodecahedron had a special resonance with me, because it reminded me of the old H. C. Kendall Planetarium in Portland, which once was enclosed by a blue and green plexiglass dodecahedron.) These puzzles were quite expensive, and I regretted not buying the third puzzle he was selling: a Skewb (a cube with off-axis joints, such that when you make a move, all six sides are changed). Years later, these puzzles actually did appear in stores, and I was glad to finally get a Skewb. It is on the shelf in my office with the other puzzles, to pique the curiosity of my students, and to remind me of many happy hours of playing with these toys.