A science that does not critically interrogate its theoretical concepts literally does not know what it is doing. The attempt to clarify a widely used concept in psychological research-the concept of concept-therefore constitutes an important effort in clarifying what role it plays in the discursive work of the field. In this commentary, I take a cultural-historical approach to suggest that the clarification of concepts requires both a genuine rupture and a historical study of the movement of a concept. Moreover, our study of concepts has to be reflexive because they are simultaneously objects of inquiry and means by which such inquiry unfolds. Rather than doing mere analysis of concept use, I propose a categorical, historical reconstruction of the concepts psychologists use.