Abstract

[NOTE: I WROTE THIS PAPER BEFORE STARTING MY PhD. SO DON'T EXPECT TOO MUCH.] Laudan and Leplin have argued that empirically equivalent theories can elude underdetermination by resorting to indirect confirmation. Moreover, they have provided a qualitative account of indirect confirmation that Okasha has shown to be incoherent. In this paper, I develop Kukla's recent contention that indirect confirmation is grounded in the probability calculus. I provide a Bayesian rule to calculate the probability of a hypothesis given indirect evidence. I also suggest that the application of the rule presupposes the methodological relevance of non‐empirical virtues of theories. If this is true, Laudan and Leplin's strategy will not work in many cases. Moreover, without an independent way of justifying the role of non‐empirical virtues in methodology, the scientific realists cannot use indirect evidence to defeat underdetermination