 This continuum problem for artifacts is really just a version of a well-known problem besetting classification schemes in the natural and social sciences. The traditional assumption was that classification is an exclusively ontological operation. What we are doing, it is often said, is carving the world at its joints. On this assumption, a continuum is a problem because it suggests that there are no joints to guide our carving efforts. A continuum is thus incompatible with classification schemes understood as grounded solely in objective features of the world, and with essentialist understandings of natural kinds. We can, of course, carve the continuum up any way we like, but this must be understood as in part a pragmatic operation, not a strictly ontological one reflecting only the fixed essences of things. This problem has loomed large in discussions of natural kinds in philosophy of science, as bothersome continua are increasingly identified in both natural and social sciences. Muhammad Khalidi (2013, Chapter 5) details cases in the chemical, biological, physiological and social sciences where widely accepted kinds are “fuzzy”, or have graded membership, for instance. In response, he advocates an account of natural kinds that incorporates the influence of human interests and epistemic concerns, while still insisting that these interests and concerns are constrained by objective features of the world identifiable by science. Khalidi’s account joins a growing list of non-essentialist accounts of natural kinds, according to which kinds are real, but their reality does not require that they be defined in total isolation from human beings, their activities, interests, epistemic projects, pragmatic concerns, and so on (Dupré 1993; Boyd 1999; Reydon 2014; Kendig 2016).