Metamorphisms

It appears that I have insufficient time, or at least insufficient discipline, to contribute to this blog, except when I am on sabbatical. Which I now am… so let’s see if I can do better. Hylomorphisms I don’t think I’ve written about them yet in this series—another story, for another day—but hylomorphisms consist of a fold after an unfold. One very simple example is the factorial function: is the