Let’s consider, in general terms, what sort of motivations one might have for adopting models that fall under the umbrella of IP. The focus will be on models of rational belief, since these are the models that philosophers typically focus on, although it is worth noting that statistical work using IP isn’t restricted to this interpretation. Note that no one author endorses all of these arguments, and indeed, some authors who are sympathetic to IP have explicitly stated that they don’t consider certain of these arguments to be good (for example Mark Kaplan does not endorse the claim that concerns about descriptive realism suggest allowing incompleteness).