Abstraction, i.e. modelling, means leaving out details. Understanding then becomes knowing what details you can leave out for the given purpose. In this context

Abstraction, i.e. modelling, means leaving out details. Understanding then becomes knowing what details you can leave out for the given purpose. In this context, it is essential to remark that scientific abstractions, i.e. physical-world, empirical theories, need to be tested experimentally. Otherwise, they will simply lack legitimacy.