The disruption of the Dutch premiere of Stockhausen's Stimmung in June 1969 has become an often-told aspect of the piece's early history, but existing accounts - including Stockhausen's own - significantly misrepresent the event. The performance was interrupted, not (as Stockhausen later claimed) by young, politically engaged composers such as Peter Schat and Louis Andriessen, but by a group of composition students who wished to 'participate' in the piece. In an impromptu debate following the aborted performance, Schat and Andriessen defended Stockhausen's right to have his music heard in silence. I interpret this clash of young Dutch musicians in terms of the sharp schism that emerged in 1969 between Amsterdam's thriving hippie counterculture, whose communal 'happenings' encouraged the dismantling of the performer-audience distinction, and the city's student movement, whose emphasis on political action found reflection in Schat's and Andriessen's growing interest in communism. It is clear, however, that Schat's and Andriessen's stance was also motivated by commitments to musical professionalism and to the ideology of musical progress, commitments that sat as uneasily with the musical preferences of the student movement as they did with the hippie counterculture.