Roussos, Joe | 2021
British Journal for the Philosophy of Science
I argue that normative formal epistemology (NFE) is best understood as modelling, in the sense that this is the reconstruction of its methodology on which NFE is doing best. I focus on Bayesianism and show that it has the characteristics of modelling. But modelling is a scientific enterprise, while NFE is normative. I thus develop an account of normative models on which they are idealized representations put to normative purposes. Normative assumptions, such as the transitivity of comparative credence, are characterized as modelling idealizations motivated normatively. I then survey the landscape of methodological options: what might formal epistemologists be up to? I argue the choice is essentially binary: modelling or theorizing. If NFE is theorizing it is doing very poorly: generating false claims with no clear methodology for seprating out what is to be taken seriously. Modelling, bu contrast, is a successful methodology precisely suited to the management of useful falsehoods. Regarding NFE as modelling is not costless, however. First, our normaive inferences are less direct and are muddied by the presence of descriptive idealizations. Second, our models are purpose-specific and limited in their scope. I close with suggestions for how to adapt our practice.