This paper revisits the concept of autonomy and tries to elucidate the fundamental insight that freedom and law cannot be understood through their opposition, but rather have to be conceived of as conditions of one another. The paper investigates the paradigmatic Kantian formulation of this insight and discusses the diagnosis that the Kantian idea might give rise to a paradox in which autonomy reverts to arbitrariness or heteronomy. The paper argues that the fatal version of the paradox can be defused (...) if we avoid the legalistic model of autonomy and rather turn to the model of participation in a practice. This leads to a dialectical understanding of the idea of autonomy that preserves the insight that freedom and law are mutually conditioning and simultaneously reveals that they remain in irresolvable tension with one another. (shrink)