Apropos the discussion Tuesday, there are further thoughts on this topic from Ilya Somin (also here; I think the parallels between being a law professor and a professor in most non-professional fields are very weak, however) and Thoreau, while Dan Drezner, Ingrid Robeyns, and Laura McKenna consider whether there’s such a thing as being a part-time academic, at least in a setting where some sort of scholarly development is expected.