The first movement is very fantastical and quite different from a typical sonata. It begins with a theme, with measures 1-8 serving as the main theme. Following this, triplets are written continuously, suggesting the composer's intention to maintain an uninterrupted flow. Incidentally, where the triplets cease, the main theme invariably reappears (e.g., measure 44).

A distinctive feature is that the melody line is written in octaves. While "cantabile" is inscribed in the author's score, it is uncertain whether this is the composer's original instruction. In any case, for this song-like section written in octaves, it is crucial to note that half the volume of a single-note rendition is sufficient, and to ensure the line does not become flat, as octaves tend to sound mechanical.

In measures 21 and 23, beats 3-4, triplets are also written for the right hand. This is left to the performer's discretion, with some playing them with a light staccato and others with legato.

There are also sections requiring a certain level of technique, such as octaves and thirds. Key points include how to smoothly navigate these difficult passages horizontally and how to maintain the musical flow without interrupting the triplets.

The piece itself is neither overly optimistic nor profound, neither dramatic nor humorous. Consider it a depiction of Haydn's fantastical side.