ABSTRACT
Most models provide a simplified and distorted rendering of their target system. To analyse what this means, both philosophers and scientists regularly appeal to the notions of idealisation, approximation, and abstraction. The aim of this chapter to get clear on what these notions are and on how they are related to each other. We begin with an intuitive characterisation of the concepts with the example of a mechanical model of a swing. We then discuss how idealisation is different from abstraction and how idealisation is different from approximation. Next, we analyse approximation and abstraction, and we reflect on the possibility of defining idealisation, which leads us to the conclusion that there is no unified definition of idealisation. An analysis of idealisation will therefore have to proceed in a piecemeal manner. This is the project for Chapter 12, in which we discuss two prevalent types of idealisations: limit idealisations and factor exclusions.
