Popular Frankfurt-style theories of autonomy hold that (i) autonomy is motivation in action by psychological attitudes that have ‘authority’ to constitute the agent's perspective, and (ii) attitudes have this authority in virtue of their formal role in the individual's psychological system, rather than their substantive content. I pose a challenge to such ‘psychologistic’ views, taking Frankfurt's and Bratman's theories as my targets. I argue that motivation by attitudes that play the roles picked out by psychologistic theories is compatible with radically unintelligible behavior. Because of this, psychologistic views are committed to classifying certain agents as ‘autonomous’ whom we intuitively find to be dysfunctional. I then argue that a necessary condition for autonomy is that an agent's behavior is intelligible in a particular way: autonomy necessarily involves acting from a subjective practical perspective that is, in principle, minimally comprehensible to others – not simply in a causal sense, but in a substantive, socio-cultural sense.