ABSTRACT
This chapter argues that simulation and understanding really are this closely linked, and that quality of simulation is the only real criterion we can apply in assessing the quality of understanding. The ability to simulate is the ability to produce, in and by means of a model, behaviour corresponding to the actual behaviour of the object simulated. Understanding, after all, is measured by the quality of the model, not by the quality of a particular simulation. The quality of the model depends on the quality of its simulations, of course, but on the whole range, not on any particular one. It argues that the nature of empirical data means that something like simulation is the only real option, thus blocking the objection that the identification of simulation with understanding is unmotivated. If models must be tested against the observed only, then maybe we could know about internal structure without having to test our simulations against it.
