Can Rationalist Abductivism Solve the Problem of Induction?

Laurence BonJour (1998) has recently proposed an a priori solution to the problem of induction. According to BonJour, it is necessarily true that explanations involving ordinary inductive conclusions are the best explanations of inductive premises, and we can be justified in believing this fact a priori. He contends that no empiricist account of justification that rejects or denigrates the a priori has any hope of solving the problem of induction. Because BonJour's claims about the problem of induction play a central role in both his critique of empiricism and his defense of rationalism, it is important to know whether the rationalist solution he offers actually succeeds. After providing a brief overview of BonJour's solution in section I, I carefully examine the probability claims that form the core of his account in sections II and III. I argue that on the most charitable interpretation of these claims, almost all of the published objections that have been raised against them are erroneous. In section IV I argue that the most serious challenge facing BonJour's account stems from the purported necessity of claims he makes about the relative frequencies of worlds within the total class of possible worlds. After reflecting on the potential circularity and circuitousness of BonJour's solution (section V), I conclude that he has failed to offer a viable solution to the problem of induction.