Formal explanations are statements that explain properties of an object by referring to its category. This study investigates the role of pragmatics in the evaluation of formal explanations. Across six experiments, we examined how a questioner's knowledge of category identity and an explanation's capability to specify a category affect satisfaction with such explanations. Experiments 1a and 1b demonstrate that participants find formal explanations less satisfactory when the questioner is already aware of the category identity. Experiments 2a and 2b show that participants assumed a questioner was unaware of an object's category if they were satisfied with the formal explanation. In Experiment 3, open-ended responses revealed that satisfied questioners were perceived as seeking to learn a category identity, while dissatisfied ones were assumed to have other motives. Finally, Experiment 4 compares tautological formal explanations (where a label points to all categories possessing a particular feature at once) and nontautological ones (where a label points to one of several competing categories), and examines the role of cognitive reflection in their evaluation. It demonstrates that people with high cognitive reflection are more sensitive to pragmatic context and value a formal explanation more if it can identify a specific category. This study shows that formal explanations are satisfactory when they fulfill a specific pragmatic function, namely, helping to define a category when the questioner knows only its feature. It also shows that people prone to automatic intuitive responses are less likely to consider this function and tend to evaluate formal explanations independently of this part of the pragmatic context.