Abstract
Thick moral concepts are a topic of particular disagreement in discussions of reasons holism. These concepts, such as justice, are called “thick” because they have both evaluative and descriptive aspects. Thin moral concepts, such as good, are purely evaluative. The disagreement concerns whether the fact that an action is, for example, just always a reason in favor of performing that action. The present argument follows Jonathan Dancy’s strategy of connecting moral reasons and concepts to those in other domains. If Dancy is correct then we should expect holism about thick moral concepts to the same extent to which we find holism for other sorts of thick concepts. Using this strategy two claims are defended: that reasons holism is characteristic of non-moral thick concepts—specifically, of aesthetic, epistemic and prudential thick concepts—and that such non-moral concepts exemplify useful and heretofore unnoticed models for thick moral concepts.