Now sonatas did not grow in Vienna. Vienna laid before her honored guests the great confusion of music which had poured into her for fifty years from foreign lands, and in that confusion were sonatas. They were but babes, frail and starved for lack of many things, little more than skin and bones. But they had bright eyes which caught Haydn’s fatherly glance. He dragged them forth from the rubbish and fed them a good diet of hearty folk-songs, so that they grew. Mozart came from many wanderings and trained them in elegance and dressed them with his lovely fancies. And at last when they were quite full-grown, Beethoven took charge of them and made them mighty. What manner of babe was this that could so grow, and whence came it to Vienna? The word sonata slips easily over the tongues of most people, great musicians, amateurs, dilettanti and laymen alike; but it is not a word, nor yet a type, easily defined. The form is very properly associated with the composers of the Viennese period. Earlier sonatas, such as those of the seventeenth century composers, like Kuhnau and Pasquini, are sonatas only in name, and not in the generally accepted sense of the word. The rock which bars their entrance into the happy kingdom of sonatas is the internal form of the movements. For a sonata is not only a group of pieces or movements in an arbitrary whole. At least _one_ of the separate movements within the whole must be in the special form dubbed by generations with an unfortunate blindness to ambiguity, the _sonata form_. Attempts have been made from time to time to rename this form. It has been called the _first movement_ form; because usually the first movements of sonatas, symphonies and other like works, are found to have it. Unhappily it is scarcely less frequently to be found in the last movements. Let us simply cut the Gordian knot, and for no other reason than that it may help in this book to render a difficult subject a little less confusing, call this special form arbitrarily the _triplex_ form. I To trace the development of the pianoforte sonata, then, is a twofold task: to trace the tendency towards a standard group of pieces or movements in one whole; and to trace the development of the triplex form of movement, the presence of which in the group gives us the somewhat despotic right to label that group a sonata.