Think of color, pitch, loudness, heaviness, and hotness. Each is the topic of a branch of physics. Benoit Mandelbrot Next Quote Until a few years ago, the topics in my Ph.D. were unfashionable, but they are very popular today. - Benoit Mandelbrot Previous Quote There is a joke that your hammer will always find nails to hit. I find that perfectly acceptable. - Benoit Mandelbrot