The same is in part true of Mozart’s sonatas. Except as these show distinct traces of the various influences under which he came from time to time, they do not differ strikingly from each other. There is over both Haydn’s and Mozart’s keyboard music a normal cast of thought, as there is over the music of Couperin. In this they suffer by comparison with Beethoven, as Couperin suffers by comparison with Bach. One would have no difficulty in choosing ten Beethoven sonatas, each one of which is entirely distinct from the others, not by reason of form or style or content, but by reason of a very special emotional significance. One could not choose ten Haydn sonatas of such varied character. One does not, in other words, sit down to the piano with a volume of Haydn sonatas, expecting to confront a wholly new problem in each one, to meet a wholly new range of thought and feeling, passing from one to the other. One looks for the same sort of thing in each one, and with few exceptions one finds it. To what is this due? To the nature of the man or to the circumstances under which most of the sonatas were written? Or is it due to public taste of the day and the consequent attitude of the man towards the function of music? To answer these questions would lead us far afield. But it is doubtless in large measure owing to this fact that Haydn, and Mozart too, have been thought to concern themselves primarily with form in music. And Beethoven has again and again been described as the man who overthrew the supremacy of the formal element in music, to which his predecessors are imagined to have sworn prime allegiance. It is a great injustice so to stigmatize Haydn and Mozart. The beauty of their music is far more one of spirit than one of form. In his own day Haydn was thought to be an innovator, not in the matter of form, but in the spirit with which he filled forms already familiar. This may be said to be the spirit of humor. Weitzmann[30] cites an interesting passage in the _Musikalisches Handbuch_ for the year 1782 which speaks of Haydn as ‘A musical joke-maker, but like Yorick, not for pathos but for high comic; and this in music most exasperating (_verzweifelt sehr_). Even his adagios, where the man should properly weep, have the stamp of high comedy.’ And a most joyous humor fills the Haydn sonatas full to overflowing. That is the secret of the charm they will exert on any one who takes the time to study them today, a charm which has little to do with formal perfection.