Do psychological perspectives constitute the only way through which the role of musical creativity in education can be addressed, researched and theorised? This essay attempts to offer an alternative view of musical creativity as a deeply social and political form of human praxis, by proposing a perspective rooted in the thought of the political philosopher and activist Cornelius Castoriadis (1922-1997). This is done in two steps. First, an attempt is made to place the pursuit of the concept of musical creativity within a larger educational and societal context of conflicting trajectories that run through (a) Modernity and (b) Education. Then, I revisit the issue of educational value of improvising and composing through creating conceptual links between the process of music-making through improvisation and composition and the project of political autonomy as conceived by Castoriadis. By foregrounding instituting imaginary over instituted imaginary, improvising and composing become active processes of positing new legitimacies, and of creating a music-making context that searches for its own foundations. It is in and through creative musical praxis that we can think about issues of hierarchies, musical values, social dimensions of different music-making processes, our relationship to past values and to historical dimensions of music. By arguing that improvisation and composition might be seen as ways of positing the issue of political autonomy in musical terms, this paper emphasises the role of improvisation and composition as a mode of potentially transformative educational practice that may foster the development of critical consciousness, linking music education to a larger project of re-discovering and at the same time re-defining democracy.