Abstract: | How do consumers assess their mastery of knowledge they have learned? We explore this question by investigating a common knowledge consumption situation: encountering opportunities for further learning. We argue and show that such opportunities can trigger a feeling‐of‐not‐knowing‐it‐all (FONKIA), which lowers consumers’ confidence in their mastery of the knowledge they already possess. Specifically, listing optional follow‐up readings at the conclusion of a course lowered students’ confidence in their mastery of the course material they had already learned (Study 1). Encountering an optional learning opportunity increased the FONKIA, which mediated the decreased confidence (Studies 2 and 3). We also document two moderators consistent with our conceptualization. First, participants primed with mastery (vs. instrumental) motivation were more negatively impacted when they encountered optional learning opportunities. Second, the more related the optional opportunities were to the target topic, the lower participants’ confidence in their mastery of what they had already learned. We conclude by discussing the implications of these findings, such as encouraging further learning or harming teaching evaluations. |