Doubts about Philosophy? The Alleged Challenge from Disagreement

In philosophy, as in many other disciplines and domains, stable disagreement among peers is a widespread and well-known phenomenon. Our intuitions about paradigm cases, e.g. Christensen's Restaurant Case, suggest that in such controversies suspension of judgment is rationally required. This would prima facie suggest a robust suspension of judgment in philosophy. But we are still lacking a deeper theoretical explanation of why and under what conditions suspension is rationally mandatory. In the first part of this paper I will focus on this question. After a critical survey of some recent alternative approaches (diversity as a thread to the reliability, decision problem, acquisition of undercutting defeaters), I will argue that in fact discovering disagreement with an opponent provides me with a rebutting defeater, but only if some further non-trivial conditions are satisfied - among them my acknowledging her as my reliability peer. In the second part of the paper I will explore in more detail the skeptical implications this account has for philosophy. Here, I will defend two claims. First, skepticism about philosophy is mandatory only if the relevant peerness assumption can be justified. Second, in philosophy there is no basis available that would support the relevant peerness assumption. If this is correct, we are not forced into skepticism about philosophy and may rationally retain our philosophical beliefs even in the face of controversy.