The article introduces a novel variety of epistemic luck, termed ‘conceptual luck.’ Informally, a singular belief \(\langle\alpha \text{ is } \Phi\rangle\) is conceptually lucky when the agent avoids a misidentification mistake by chance in forming it. Unlike the so-called veritic luck—i.e., luck that a belief happens to be true—, conceptual luck primarily concerns the agent’s deployment of singular concepts in belief-formation, not the belief’s truth value. The article characterises this form of luck and argues that, although distinct from veritic luck, conceptual luck is knowledge-undermining. To support this claim, it presents cases where conceptual luck occurs without veritic luck, and the agent is intuitively judged too lucky to achieve knowledge; then, it introduces a general procedure for generating such cases. To reinforce the conclusion, the article also develops a first-principles argument grounded in the idea that knowledge is a mental state constitutively involved in explaining intentional action. It further explores the implications of conceptual luck for globalised safety principles, its implication for direct coordination for singular thoughts, and other additional objections.
