In his operas, Mozart followed contemporary practice by using the clarinet to set the mood for amorous scenes, but he adapted this into a new kind of topic that dramatises his characters’ changing self-knowledge and growing enlightenment. In so doing, he emphasised both their recognition of their true feelings and the political and moral implications for their subsequent actions. This is exemplified in La clemenza di Tito, in which a clarinet (or basset horn) serves as an important soloistic voice whose dialogue with the protagonist illuminates their inner struggles with conflicting emotional, social and political realities as they move towards new understanding.

Compositions for musical clocks made possible a newly objective exploration of the relationship between music and time. Works by George Frideric Handel, Wilhelm Friedemann Bach and Carl Philipp Emanuel Bach reflected the absolute and uniform flow of Newtonian time. In contrast, Leopold Mozart's clock music alternated between two different metres and Wolfgang Amadeus Mozart used more complex tempo ratios in a musical installation (k608) built around a dramatically illuminated pendulum. Repeated thousands of times, this installation pitted clock against music, in effect providing a new kind of experiment that favoured relative Leibnizian time over uniform Newtonian time. As if responding to k608, Joseph Haydn incorporated his own clock music into his Symphony No. 101 in order to underline, yet then to stop, time, while Schubert's Fantasy in F minor, d940, brought these temporal experiments into a new realm of intimate musical experience.

In June 1791, having composed almost no church music for ten years, Mozart wrote the short motet Ave verum corpus, k618, a setting of the Latin medieval eucharist hymn. The theological teleology in the text introduces a process-like aiming at a goal that cannot, however, be reached. This study is about how teleology operates in the motet – the ways in which the text's ultimately unfulfilled goal-directed processes operate in Mozart's music. The music is approached from a variety of analytical perspectives that reflect different aspects of this theme: the new Formenlehre and phrase structure, topic theory, and the analysis of voice-leading structure, register and hypermetre. Together, these approaches elucidate the multiplicity of musical processes that, as in the motet's text, announce a goal but fail to reach it.