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Chapter 3. Naming > Uniqueness, Scope, and Qualifiers - Pg. 74

74 Data and Reality As Kent stated, a very good use of abstraction is to create new concepts (such as "message destination") that mask the ambiguity of existing concepts. It may not solve the underlying data issues, but it will give us a "bucket" to put everything in, so eventually the data issues can be resolved by looking in one place. A familiar message again: you the observer are free to choose the way you apply concepts to obtain your working model of reality. Uniqueness, Scope, and Qualifiers Whether a name refers to one thing or many frequently depends on the set of candidates available to be referenced. This set of candidates comprises a "scope," and it is often implicit in the environment in which the naming is done. A reference to "Harry" is often understood to mean the Harry present in the room. A letter addressed to Portland (without naming the state) will probably be delivered in Oregon if mailed on the West Coast, and in Maine if mailed on the East Coast. The boundaries of a scope, and the implicit default rules, are often fuzzy: I don't know where the letter would go if it was mailed in Illinois. Recall our earlier discussion on context. "What is the scope of uniqueness?" is a frequent question heard from the analyst or modeler. The broader the context, the