I explore conceptual tensions that emerge between Wilfrid Sellars’ and Grace de Laguna’s adoption of behaviorism. Despite agreeing on various points (e.g., the social nature of language and behavior, a methodological commitment to behaviorism), I argue that Sellars’ and de Laguna’s positions represent a split between normativist and descriptivist approaches to explanation that are generally incompatible, and I explore how both positions claim conceptual priority.