Abstract
Conceptual engineering is concerned with the improvement of our concepts. The motivating thought behind many such projects is that some of our concepts are defective. But, if to use a defective concept is to do something wrong, and if to do something wrong one must be in control of what one is doing, there might be no defective concepts, since we typically are not in control of our concept use. To address this problem, this paper turns from appraising the concepts we use to appraising the people who use them. First, I outline several ways in which the use of a concept can violate moral standards. Second, I discuss three accounts of moral responsibility, which I call voluntarism, rationalism, and psychologism, arguing that each allows us to find at least some cases where we are responsible for using defective concepts. Third, I answer an objection that because most of our concepts are acquired through processes for which we are not responsible, our use of defective concepts is a matter of bad luck, and not something for which we are responsible after all. Finally, I conclude by discussing some of the ways we may hold people accountable for using defective concepts.