 Hacking (1995) employs feedback mechanisms in a different way: rather than emphasizing stability, he regards causal change to be characteristic of “human kinds”. Hacking argues that human kinds are generated through histories of causal loops, in which objects having a cluster of properties are named as being members of a kind. That label then affects the property cluster that they have, which changes the classification, and so on repeatedly, with human interests changing the properties that get classified into the category. Hacking discusses the example of the kind refugee, in which categorizing people as refugees changes how they are treated, which then loops back to affect how we categorize refugees. In Hacking’s account, each loop includes a mentalistic aspect—the classification—and an instantiated aspect—the causal effects on the properties. Butler 1993 and Hayles 1999 develop accounts of the looping effects of classification systems on human bodies (see also Schilling 2001). Mallon (2003, 2016) combines the looping theories with homeostatic property clusters, and applies them to social kinds, races in particular.