Originally Posted by badhatharry
So what would be your simple, obvious answer to my question?
Those mathematical equations make up a model that attempts to recreate the behavior of a real economic system in the way that a map recreates the land it describes. The model will make predictions about how the system will work in different situations. If those predictions turn out to be accurate, then we can conclude that the model is probably a mostly accurate depiction of reality. If they don't, then we need to find a new model or revise the old one.