The Wedding Album analogy

Diagrams in a model should all serve a purpose. They are user defined views of the model. Lenny Delligatti makes an analogy that views are like photographs. In his book SysML distilled: a brief guide to the systems modeling language, Pearson Education Inc., ISBN 0-321-92786-9, Lenny cites photographs of a mountain. The mountain exists in 3D regardless of whether you take pictures of it. Different pictures can view the mountain from different angles.

I like using the analogy of the modeler being like a photographer at a wedding because the wedding photographer doesn’t just take pictures but they make choices about what to put in them. They are responsible for capturing key moments and forming who is in what photograph. Each picture in a model tells a different story (separate families, the grandparents, friends not enemies, love, even the pets). Increasingly with social media and high quality phone camera’s, people can form their own album from multiple people’s views. 

To me this is what modeling is like. It helps manage complexity by presenting different views; structural, behavioral, traceability but with a single source of truth (the model).