According to Ian Hacking, some human kinds are subject to a peculiar type of classificatory instability: individuals change in reaction to being classified, which in turn leads to a revision of our understanding of the kind. Hacking’s claim that these ‘human interactive kinds’ cannot be natural kinds has been vehemently criticized on the grounds that similar patterns of instability occur in paradigmatic examples of natural kinds. I argue that the dialectic of the extant debate misses the core conceptual problem of (...) human interactive kinds. The problem is not that these kinds are particularly unstable but ‘capricious’—their members behave in wayward, unexpected manners that defeats existing theoretical understanding. The reason for that, I argue, is that human interactive kinds are often ‘hybrid kinds’ consisting of a base kind and an associated status, which makes mechanisms that support patterns of change and stability systematically difficult to understand and predict. 1Introduction2The Extant Discussion 2.1Hacking’s account of interactive kinds2.2Classificatory feedback in non-human kinds3Natural kinds and Ontological Instability 3.1Understanding instability3.2The problem of stabilizing feedback3.3Summary4Capricious Kinds 4.1Biased conceptualization4.2Studying social status5Conclusion. (shrink)