In this chapter, I argue that interest (or interestingness) can serve as a reliable guide to the detection of important research topics, but only under specific conditions. My argument begins by reflecting on a specific cultural difference between the natural sciences and the humanities that exemplifies the disparate roles that interestingness plays in the two domains. I explain how this specific difference is a symptom of a much more far-reaching contrast between them, and this contrast tracks differences in the tendency of something of genuine scholarly significance to emerge from the pursuit of research questions that one finds interesting. I argue that disciplines whose members do not agree on a large corpus of substantive claims — in short, disciplines in which consensus is a rarity, if it exists at all — do not function as intellectual communities capable of cultivating a causal link between something’s being interesting and something’s being important.