from: http://www.systems-thinking.org/simulation/model.htm

Model

Model, like so many words in the English language, has a multitude of meanings depending on the context in which it is used. In a systems context I have come to understand model to mean:

A simplification of reality intended to promote understanding.

We often deal with things, later I'll call them systems, that are so complex as to be beyond the limits or our intuitive comprehension. As such, we construct models, simplifications of the real thing, which allow us to study that which we seek to understand.

Whether a model is right or wrong is simply a value judgment, whether it is correct or incorrect is something that will be evident in time. The most important question to ask should relate to the extent to which the models we develop promote the intentioned development of our understanding. The extent to which a model aids in the development of our understanding is the basis for deciding how good the model is.

In developing models there is always a trade off. A model is a simplification of reality, and as such, certain details are excluded from it. The question is always what to include and what to exclude. If relevant components are excluded there is a chance that the model will be too simple in nature and will not support the development of the understanding desired. On the other hand, if too much detail is included, the model may become so complicated that, again, it fails to promote the development of the deeper levels of understanding one seeks. One cannot develop every model in the context of the entire universe, unless of course your name is Carl Sagan.

-- AnarchistU - 24 May 2006