The Toccata e due canzoni. H 311, is evidence of Martinů's mature expression in which, as Virgil Thomson said, "the shining sounds of it sing as well as shine, the instrumental complication is a part of the musical conception, not an icing laid over it." Martinů originally imagined both canzonas as "light, playful, and very simple songs". After some time, however, he found that regardless of his intention they were developing entirely in their own way and there was nothing he could do about it. The dark atmosphere of the second canzona was caused partly by outward circumstances: while composing it Martinů suffered a serious injury which resulted in a fractured skull, a hearing defect, and vertigo.
Aleš Březina, programme of the Bohuslav Martinů Festival's concert, December 10, 2001