Two later sonatas have a more serious _allure_ than these earlier ones. That in C minor (K. 457), composed in 1784, is commonly considered his greatest sonata. Why such a distinction should be insisted upon, it is difficult to see. The C minor sonata is more weighty than the others, but is it for that reason greater? Must music to be great, hint of the tragic struggles of the soul? Such is the merit often ascribed to this sonata, as if there were no true greatness in a smile. Without setting up a standard of the great and the trivial in music, we may grant that the work has a compelling force. Let us not liken it to Beethoven. It still has the charm of which only Mozart was the master, that charm which remains one of the intangible, inexplicable things in music. A sonata in F major (K. 533) was composed in 1788. The whole work is characterized by a possibly too prominent contrapuntal ingenuity. There is besides a boldness in harmonies, especially in the slow movement, which makes one wonder into what strange lands Mozart strayed when he sat improvising at the keyboard. The sonatas as a whole rest, as we have said, upon a harmonic foundation which is relatively simple. The great Fantasia in C minor differs from them in this regard more than in any other. If, as Otto Jahn suggested in his ‘Life of Mozart,’ this fantasia may offer us some suggestion of what Mozart’s improvisations were like, we may be sure that such outpourings wandered into harmonies rich and strange. The fantasia was composed in 1785, the year after the C minor sonata, to which it was at one time thought to have been intended as an introductory movement. An earlier fantasia in D minor is fragmentary. It ends abruptly and leaves an impression of incompleteness on the mind of the listener. The C minor fantasia is without definite form, but the return of the opening motive at the end gives it a logical balance. It divides itself into five or six sections. The tempo is not very fast in any one of them, but there is an uneasy current of unrest running under the whole.