This paper examines Ian Hacking's analysis of the looping effects of psychiatric classifications, focusing on his recent account of interactive and indifferent kinds. After explicating Hacking's distinction between 'interactive kinds' (human kinds) and 'indifferent kinds' (natural kinds), I argue that Hacking cannot claim that there are 'interactive and indifferent kinds,' given the way that he introduces the interactive-indifferent distinction. Hacking is also ambiguous on whether his notion of interactive and indifferent kinds is supposed to offer an account of classifications or (...) objects of classification. I argue that these conceptual difficulties show that Hacking's account of interactive and indifferent kinds cannot be based on - and should be clearly separated from - his distinction between interactive kinds and indifferent kinds. In clarifying Hacking's account, I argue that interactive and indifferent kinds should be regarded as objects of classification (i.e., kinds of people) that can be identified with reference to a law-like biological regularity and are aware of how they are classified. Schizophrenia and depression are discussed as examples. I subsequently offer reasons for resisting Hacking's claim that the objects of classification in the human sciences - as a result of looping effects - are 'moving targets'. (shrink)