Ian Hacking receives acknowledgment in the literature on social ontology in large part because of his well-known account of looping effects as constitutive of social kinds. What has not received similar emphasis concerns the fact that Hacking insists that kinds so constituted prove inherently unstable, and as a consequence he maintains they cannot be a basis for any science of the social. His argument reflects the centrality that the stability of kinds of objects plays in Hacking’s project regarding styles of scientific reasoning and so of having a science of a particular subject matter. A focus on this aspect of kind-making brings to the fore then questions regarding whether and how social ontologies could sustain a science of the social. I examine how some contemporary literature has attempted to incorporate Hacking’s account of looping effects, and whether or not these projects fail for reasons related to Hacking’s skepticism about social kinds and the categories of things needed to support scientific reasoning. Hacking’s work thus underscores questions about the relation of social ontology and scientific explanation that highlights issues about explanation that remain largely unaddressed within contemporary philosophy of science in general and philosophy of social science in particular.