This may set a record for my shortest diary post. Well, it’s gotten longer than I thought it would be, but not by much.

I could just put one or two links out here, but let me make it an honest post.

As I finished reading a book last Saturday, I decided that I was probably coming down with a cold. The timing was wrong for it to be my mild allergy to my own cats — that kicks in in the morning when they are both sleeping beside me. I went out and bought chicken soup, frozen foods, and some medicine. I had a large supply of paper towels (10 rolls).

I was right, it was a cold. It never got very bad, never moved from my head to my throat, but my eyes hurt sometimes from the congestion.

It was, however, ironic. The book I had just finished reading was “The Great Influenza” by John M. Barry — the story of the deadly flu pandemic at the end of World War I.

I read when I could, watched TV when I couldn’t read. I did a little mathematics, but not much — and I’m still trying to catch up.

I am working on a logic post, and on the mathematics of orbits… and I’ve been playing with the fast Fourier transform and color. We’ll see if I get the logic post done this weekend.

I was more successful at rereading “Guns, Germs, and Steel” by Jared Diamond.

Rather than try to write an essay about something, let me give you two links.

The first one is a general link to mathematics in the movies, collected by a professor at Harvard.

The second one is a specific link to a really cool piece of mathematics from a “Ma and Pa Kettle” movie, in which they demonstrate that 25 divided by 5 is 14.

Yes, it is really cool even though it is really wrong. What stunned me was that after failing to convince somebody of the division, the characters attempt to demonstrate the result by multiplication — and failing at that, they attempt to demonstrate it by addition.

I was stunned when I saw it. But 70 years ago there was a screenwriter who knew that you could check a division by doing multiplication, and you could check a multiplication by doing addition. I suspect that 70 years ago that understanding wasn’t unusual.

You might find it very instructive to isolate the mistake Ma and Pa Kettle are making. And, like me, you might get a kick out of the movie.