ABSTRACT. Although causation may be an inappropriate concept to use in describing the influence that one musical event is perceived to have on another, the notion of implication is intuitively apposite. Viadana argues that confronted with the text of a piece of music, the performer will engage in a brief preliminary assessment, in order to get a rough sense of the piece's requirements. Either cases in which a work appears to be flexible are really cases in which there is more than one (inflexible) work.