Why do the classical sonatas maintain this scheme of self centred movements with no community of theme? The answer to this lies in the relation between their time-scale and their emotional content. In its early forms the sonata is a new kind of suite, complete in its contrasts. In its later developments the individual movements, while complete as designs, raise emotional issues which each movement is unable to satisfy without the others. The first movement of Beethoven's not inaptly named Appassionata sonata (Op. 57) whirls us through an immense tragedy in eight minutes. The movement is irrevocably com pleted ; but our emotional reactions have not more than begun. We need the unutterable calm of the slow movement with its theme rooted to its tonic chord, and its simple and solemn varia tions in the ancient form of doubles. A foreign chord replaces that of its cadence; the vision is broken and the finale rushes headlong to the end of a tragic fate. The whole emotional scheme is perfect; but for one movement to take up the themes of another would be to tell a twice-told tale. Hence the classics, including Brahms, are not only cautious but cryptic in the few cases where they allow one movement to allude to another. The only occasion for clearness in such allusions is with introductions, which may well foreshadow the following movement, and, in the case of introductions to finales, may dramatically recall the past.
The emotional unity of the sonata is already significant in Mozart and Haydn. Their artistic hypotheses are those of comedy; and even so tragic a note as the last page of Haydn's F sharp minor quartet (Op. 5o, no. 4) can be sounded only in the severe form of fugue. One of the most significant gestures in all the history of music is that of the introduction to the finale of Mozart's G minor quintet. The slow movement is one of the pro foundest things possible before Beethoven. One is inclined to resent the notion that such music can have limitations. Being perfect it is infinite, and you cannot compare infinities. But you can be clear as to their elements; and the terms of its art forbid this pathetic music to handle tragic action. For tragedy, music needs such resources as are shown in Ex. 7, and these would shatter Mozart's aesthetic system. But after that slow movement even the finale of Mozart's own G minor symphony would sound peevish. So Mozart writes a solemn slow introduction which bids the art of music run away and play, for the rest is too sad for it. And so the bright rondo-finale is another story. Mozart would neither violate his aesthetic system nor anticipate Mendelssohn's naive way of striking a religious note with a com plete unconsciousness of its blasphemy.
The Sonata Since Beethoven.—The sonata-style belongs to the sonata time-scale and to the classical key-system. Music in the Wagnerian time-scale, or in "atonal" or other new harmonic systems, has no more to do with it than Greek prose. Nor do changes in the general outlines of the form mean much in them selves. The classical forms are, even externally, far more varied than those of later sonata-works ; and the essentials of the sonata lie much deeper.
Schubert achieved wonderful things in his sonata works, but died before he had perfected his forms. His expositions digress
into developments, his developments subside into long twice repeated lyric episodes, and his recapitulations reveal that re capitulating is the very thing his expositions are not designed to bear. Nevertheless Schubert was on the high road towards genuine new forms.
What these forms were to be was best revealed by Brahms. It is fashionable to deny that Brahms invented new forms; and this is like Humpty-Dumpty's complaint that Alice's features were arranged so exactly like other people's that he could not be ex pected to recognize her. Forms must be studied in detail from phrase to phrase, and classified afterwards : not classified by guess work and warped to fit the guess. Brahms has many new ways of phrasing and of developing themes (see MELODY, Ex. I I); and no two of his forms are alike. Least of all composers does he resemble Schumann, whom he was at first accused of imitating.
Schumann's sonata works show an interesting artificial system. His ideas were lyric and epigrammatic ; and they shaped them selves squarely and with a Macaulayesque habit of antithesis. With this style he contrived to build important sonata works as one might construct a landscape in mosaic. He knew what he was doing, and the result is often delightful. In his D minor symphony he achieved a new continuity of form and theme, retaining the classical group of four main movements, but running them to gether without break and using transformations of the same themes in all four. Schumann's hard outlines and square rhythms have been copied without his wit in countless later sonata especially by those Russian composers who, led by Nicolas Rubin stein, danced upon his grave in derision of these very features.
Mendelssohn handled all sonata forms with an often dangerous facility but sometimes with genius. The opening of his D minor trio is the prototype of those innumerable allegros which are really andantes riding an ambling horse or running up a descending escalator.
The masterly scheme (there is only one) of Spohr is (as i Schumann remarked) not so easy to imitate as it looks; but it is the prototype of most pseudo-classical works up to the present day; and many teachers believe it to be the only orthodox form. Against such teaching young artists do well to revolt, but why call it classical? The quality most conspicuously absent in sonata-work since Brahms is movement. The fundamental mistake of Bruckner (q.v.) was in associating his Wagnerian style with sonata forms at all. Sibelius solves Bruckner's problem, and takes and leaves the sonata style as he pleases, and always with clear purpose, whether convincingly or not. Reger's meticulously regular forms are hard to accept as the really proper vessel for his strong chromatic brew; and as for imitating him, one might as well try to write a Mere dith novel from one metaphor to the next. The art of move ment is the crux of the sonata problem ; and the classical solutions of it from Haydn to Brahms are the greatest things in pure music.
(See also SYMPHONY; SONATA; MUSIC; VARIATIONS; RONDO; SCHERZO; and the articles on the various individual composers who have been referred to.) (D. F. T.)