See, here is a good example. I spoke about different theories and interpretations. You are using the term "schools of thought". What does each of us mean?? By way of illustration: I understand the typing system we refer to as MBTI to be based on Jung, but as elaborated and modified by Myers and Briggs. Yes, Gifts Differing is the fundamental reference on the basic theory. When I write of interpretations, I mean the further work of people like Kiersey, Beebe, Thomson, and others. They all use the basic 4 dichotomies, all address function attitudes in one way or another, all come up with 4-letter type codes, etc. One of their most significant differences in my reading is how they deal with functions after dom/aux, or even after what we often refer to as dom/aux/tert/inf, in short, the 4 least preferred functions. Referencing MBTI theory is more akin to quoting the Bible or the U.S. Constitution. We can all know the basic text and its history, but may still interpret and apply it in different ways.