We suspect that most of you figured out that the spots could be viewed as a spotted dog -- a Dalmatian -- drinking from puddles on a rainy street seen through the shadows of leaves on a tree. (OK, we're elaborating a bit here.)

Typically, two or three out of 100 people looking at the figure on the previous page will have trouble seeing the dog in the spots. If you don't see how this figure appeared in the plain spots, flip back and forth between the last page and this using your browser's arrow icons.

Your brain pulls the spots into a coherent picture; and that's what we want you to do with the knowledge you're learning in this class -- make sense of it. 

For many students in this class, making sense of the complex equations we'll be using is a non-trivial task. Throughout, as we bring up equations we'll talk about seeing the dog in the equation -- finding a way to make sense of what the equation is trying to tell us. It doesn't do much good to try to memorize the bits of the equation without the sense. It would be like trying to reproduce the picture here by memorizing each of the independent spots!

We'll call up the icon of the spotted dog to remind you to try to make sense of what we are doing -- creating a coherent whole.