Galileo's Pendulum

Into this Universe, and Why not knowing Nor Whence, like Water willy-nilly flowing; And out of it, as Wind along the Waste, I know not Whither, willy-nilly blowing. (from the Rubaiyat of Omar Khayyam) (Edited: my first version made it sound like I just make stuff up as I go along while teaching, which certainly…