Jon, I like where you are going with this and admire your tenacity to clear a path through this challenging terrain. When I read your description above, it reminds me a bit of the lattice structure of personal organization that John and Judith desribe in Turtles All The Way Down. Could you clarify what you mean by "source" and "function." I think I know where you are going and also realize that, in some cases, "thinking I know" is an obstacle to learning (or as Mike wrote in another thread "arrogance (pride) comes before the fall"). Another question I have regarding the structure of the database regards syntax of the patterns within a model; in other words, are some patterns prerequisites for others? - Ulic