John and Carmen, In Whispering, p. 41, 2nd indented paragraph you both discuss the relevancy of noting that all modelling has a certain arbitariness to it. That "there are a large number of ways of carving up such interactions so as to create a model. This arbitrary quality of modeling is constrained by several variables that reduce its arbitrariness, although these constraints do not approach making it deterministic." You follow with two examples using the subject matter of a flashlight (e.g Model A, Model B) demonstrating how these descriptions are for fundamentally different purposes. My question is this... For many years we have heard how important a well-formed outcome is to process of modeling. Would either of you explain the difference, if any, between outcome and purpose?