Agreed. I am amazed at some people's inability to separate fact from assumptions.
Wiki - Scientific Modelling, sums it up.
Modelling as a substitute for direct measurement and experimentation
Models are typically used when it is either impossible or impractical to create experimental conditions in which scientists can directly measure outcomes. Direct measurement of outcomes under controlled conditions (see
Scientific Method) will always be more accurate than modelled estimates of outcomes. When predicting outcomes, models use
assumptions, while measurements do not. However, it is important to note that in analyzing the data collected from measurements, assumptions are made albeit different to those made through the use of a model.
As the number of assumptions in a model increases, the accuracy and relevance of the model will likely diminish.
These models use assumptions and insertion values that come from other models using assumptions and probabilities etc.
Yes, theory and assumption mean much the same and neither are facts nor evidence.