Abstract
This paper argues that conceptual engineering comes in many guises, often depending on what type of concept is being engineered. Engineering a classical concept, one that stems from Plato and Frege, is very different from engineering, e.g., a prototype concept or an exemplar concept. The former are abstract and have necessary and sufficient satisfaction conditions. The latter, on the other hand, can and do differ from one person to the next and thus have the earmarks of conceptions. While it is tempting to argue that classical concepts are of natural kinds while prototype and/or exemplar concepts are of socially constructed kinds, the paper argues that such classification is not tenable. Many of our concepts of natural kinds are prototype concepts, and many socially constructed kinds are specified with necessary and sufficient conditions and so are have the earmarks of classical concepts. While the discussion of conceptual engineering has mostly focused on classical concepts and how scholars can, do, and perhaps should ameliorate them, the paper emphasizes the importance of other types of concepts and how they can be engineered.