What is one doing when one improvises music, as one does in jazz? There are two sorts of account prominent in jazz literature. The traditional answer is that one is organizing sound materials in the only way they can be organized if they are to be musical. This implies that jazz solos are to be interpreted with the procedures of written music in mind. A second, more controversial answer is offered in David Sudnow's pioneering account of the phenomenology of improvisation, (...) Ways of the Hand. Sudnow claims that learning to improvise at the piano is concerned centrally with copying the bodily ways of one's mentors and finding how one's instructable hands and the keyboard come to answer to one another, so that "to define jazz ... is to describe the body's ways." But despite its greater sensitivity over the traditional account, Sudnow's account is flawed both as a description of how improvisatory skill is acquired and as a model for describing the interest of jazz. My critique of Sudnow compares his account to Augustine's account of learning language, and finds that Wittgenstein's criticisms of Augustine extend to Sudnow. I offer a third approach to understanding improvised music, one which treats the procedures of improvisation as derived from, and importantly at play in, our everyday actions. (shrink)