First movement, this Sonata takes us into new realms of lyricism - we suppose that this is inherent in Mozart's choice of key. The first movement opens with a cantabile theme which no one else could have written. It should be noted that measures 3 4 (with upbeat) are a variation of the initial phrase. A minor Italian composer might have repeated the opening statement one step lower; it still would sound well, but it would not be comparable in any way to the beauty of Mozart's theme. The wealth of melodic and thematic inventions here and in the rest of the Sonata is simply staggering. How simple, in comparison, is Beethoven's structure in his Sonata in the same key of B-flat, op. 22! In this Sonata Mozart anticipates in more than one way the 'heavenly length' of some of Schubert's Sonatas. Second movemet, according to Daniel Schubart's aesthetic theory, E flat, the key of the middle movement, was the key 'of love, prayer, intimate converse with the Almighty, signifying the Trinity with its three flats' a characterization which does seem to apply, for once, to this rather solemn and profound Andante cantabile movement. It is in sonata form, and sometimes gives the impression of having been conceived as a string trio. One of the boldest moments is the beginning of the development with its biting dissonances, all the more telling after the preceding euphony. Third movement, the somber ethos of E flat is dispelled by a concertante Rondo finale in B flat, although this good-humoured movement does retain a touch of seriousness a sufficiently weighty conclusion to this fine Sonata. Several features - not least the tutti entry preceding the cadenza (m. 168) - suggest that this is a concerto movement in disguise. The insertion of a full-scale cadenza (m. 171) into a piano sonata movement is most striking, and this powerful one is only rivaled in Mozart's Concertos. It far surpasses those in Haydn's and C.P.E. Bach's Sonatas. Paul and Eva Badura-Skoda