Jonathan Harvey's Curve with Plateaux (1982) for Solo Cello.
Published by Faber Music.

'This work takes as its starting inspiration a model of human personality. At the bottom of the cello register is the “physical” – arms, legs, muscles, etc. Next in the tenor register is the passionate level. Above that lies the level of thought, which becomes even more refined and delicate as it rises to the top of the cello where the level of transcendence is suggested. The line then curves back to its starting point and finishes with suggestions of mortality.'

~ Jonathan Harvey