Originally pitched as trying to articulate an idea that you can't quite place, this work is a tour de force for the instrumentation. The theme rotates through various voicings and styles in a sonata structure but is never stated in its entirety until the recapitulation. An aggressive opening section is followed by a modal, meditative slow setting before being thrown into chaos and resolving to a jubilant statement of the theme in its entirety and a virtuosic piano coda.