Ligeti was nearing the end of his schooling in 1948 and had already established himself as a highly gifted student.
[1] In this year, he composed the Dialogo, which would later become the first movement of the Sonata, for a female cellist and fellow student at the Budapest Music Academy, Annuss Virány, with whom Ligeti was "secretly in love."
[2] Virány purportedly was not aware of the reason behind Ligeti’s generosity; she merely thanked him and never played it.
[3] Several years later, in 1953, Ligeti met Vera Dénes, an older and more celebrated cellist, who asked him for a piece of music.
[4] Having written only one unperformed cello work to date, Ligeti offered to expand the Dialogo into a "two-movement short sonata," adding a virtuosic Capriccio movement.[5] With the country still under Soviet occupation, Ligeti was required to subject all his compositions to the scrutiny of the Communist-controlled Composers’ Union, at the risk of losing his job.[6] He later recalled his interaction with the Union: