From Ptolemy to Heisenberg: Quantitative models and reality

An aspect of methodology in research in the field of design economics and cost modelling is described, discussed and evaluated. This review is designed for post-graduate students and built-environment professionals embarking on a PhD in that field. Models, built using methods regarded as 'scientific' at the time, have enabled us to solve specific problems and to learn more about the world. A generalized approach to building and testing symbolic models is outlined. In conclusion, a number of limitations are identified which are inherent in the conventional quantitative modelling approach.