This chapter explores the ontological implications for Michael Finnissy’s music through the ways in which it is framed in Theocharous’s article, illustrating the ways in which inappropriate ontological frameworks can hamper the performance, comprehension, and study of Finnissy’s music. An ontology which maintains a causal distinction between the musical work and the musical score is platonism. Goodman was able to account for other notational aspects of paradigmatic Western Music, such as free cadenzas, and figured-bass, by conceiving of them as notational-subsystems, and as such notational compliance is feasible. A platonic understanding of musical works states that they exist as abstract sound structures – non-spatiotemporal, and acausal – they exist outside of experiential time and location, and exist regardless of anything causing them to exist. The way in which sound structure performing-means are expressed is through musical scores. A system of symbols, such as musical notation, according to Goodman, can have the property of being either ‘notational’ or ‘non-notational’.