[Cynthia Daniel]

I was always surprised this topic never really took off since I find it fascinating.

Here's an interesting page about Leonardo da Vinci and his use of the Golden Rectangle. Be sure to mouse-over the images and you'll see the golden rectangles.
http://library.thinkquest.org/27890/applications6.html

That page is within a larger dicussion on the Fibonacci Series. Here is an introduction: http://library.thinkquest.org/27890/theSeries1.html

And, here is about the Fibonacci series in nature: http://library.thinkquest.org/27890/theSeries1.html

Perhaps this explains why four people in a painting are difficult in terms of creating an aesthetic composition. The number 4 is not a number in the Fibonacci series.