is a term introduced by Ian Hacking to refer to the kinds of people—child abusers, pregnant teenagers, the unemployed—studied by the human sciences. Hacking argues that classifying and describing human kinds results in feedback, which alters the very kinds under study. This feedback results in human kinds having histories totally unlike those of natural kinds (such as gold, electrons and tigers), leading Hacking to conclude that human kinds are radically unlike natural kinds. Here I argue that Hacking's argument fails and that he has not demonstrated that human kinds cannot be natural kinds. Introduction Natural kinds Hacking's feedback mechanisms 3.1 Cultural feedback 3.2 Conceptual feedback.