Daniel Gregory Mason

CHAPTER IV
THE PRINCIPLES OF PURE MUSIC

Just as success in the intellectual and moral worlds results from power to shape ideas and conduct, to make syntheses which combine the most various elements in unity, so artistic success results from the power to shape into a single organism the various elements of artistic effect. Art may make a deep appeal to us by the richness of its sensuous charm, and a still deeper by the eloquence of its emotional expression; the deepest of all appeals it will not make, we have asserted, unless, by marshalling its materials into an obvious order, it adds to its sensuous and expressive charms the Æsthetic charm, the greatest of all—beauty. Art, we hinted, was beautiful in the proportion of its unified variety; and we set ourselves to see what methods men gradually worked out, in the seventeenth and early eighteenth centuries, by which the wonderfully various effects of their new music could be stamped with final unity.

In the fact that they attain beauty through the presentation of variety in unity, all the arts are alike; yet they differ much in the way they accomplish this end, because of their differing conditions. Those arts, notably sculpture, painting, and architecture, which adjust their materials in space, necessarily use methods quite different from those of the temporal arts of literature and music, which, existing solely in time, have no spatial relations of any sort. The spatial arts, presenting all their elements simultaneously, differentiate and at the same time interlink them by means of relative position, size, and prominence. In a well designed figure or group of figures, in sculpture, there is always a balance of masses, by which the whole work, however diverse in detail, is knit into unity. The centre of gravity is kept well in toward the centre of the entire mass; all the features at the extreme edges lead the eye back to the middle to rest; there is centralization of effect, balance, poise. In a good picture, all spots of high light, all prominent lines, all striking lineaments of every sort, are similarly contrived to equalize the tensions of the eye, to keep it in that state of attentive rest, or anchored discursiveness, which is so indescribably delightful. The same is true of all well-proportioned buildings and other architectural monuments. Activity of eye and mind are stimulated, but also governed and directed. Howsoever the eye, in looking at any good picture, statue or piece of architecture, may quest and rove, it is constantly brought, by the gentle power of good design, back to the centre of rest; the sense of interesting variety is always wedded with the sense of ultimate completeness and repose.

In the temporal arts of literature and music the same effect is gained by quite different means. Here the elements are not presented simultaneously, spread out for the attention to wander from and revert to at will. Each is presented but for a moment, after which it exists only in the memory. Nevertheless all literature and music worthy the name of art give us, in common with the spatial arts, the sense of symmetrical shape, of ordered profusion. Though we are aware of each single lineament but for an instant, after which it is supplanted by the next, yet we know that all combine into just as complete and satisfying a scheme as that of the well-designed statuary group, the well-composed picture, or the well-proportioned building. This consciousness of form or design in a series of momentary impressions, on which all the high Æsthetic value of the temporal arts depends, is made possible to us by our mental powers of memory and recognition. Literature and music deal with memorable units, which are repeated. Familiarity with their methods quickly accustoms us to expect the repetitions; whereupon there arises a succession of expectations, followed by their fulfilments, by which the so fleeting impressions are arranged in our minds in a fixed and satisfying order. And so arises the sense of beauty in the contemplation of a poem or a piece of music.

In poetry two different modes of repetition are utilized, each arousing its own peculiar expectation, which combines with its fulfilment to give the sense of order. The first mode is that of metrical repetition, the establishment and reiteration of a certain scheme of accentuation of syllables practically equal in duration. In heroic verse, for example, the scheme is a succession of ten syllables, every alternate one accented, and beginning with an unaccented. When a single line of this sort is heard, it forms a pattern in the mind, and arouses an expectation of another of the same sort. The fulfilment of the expectation gives rise to the sense of form. In rhymed verse, a second kind of repetition is added to this fundamental metrical one, namely, the repetition of the terminal sound of the line. When we read “’Tis not enough no harshness gives offence,” the obviously regular character of it in respect of accent leads us to expect very confidently another line of the same metrical structure; and our familiarity with rhyme disposes us to think it highly probable that the new line will moreover end with a sound similar to the final one in “offence;” so that when the line comes—“The sound must seem an echo to the sense,”—it fulfils both of our expectations, and we get a double sense of design in it. The rhythm, or reiteration of the metrical scheme, is supplemented by the rhyme, or repetition of the terminal sound. In the more complex forms of verse the two schemes of design not only become far more subtle in their single application, but are made to cooperate and reinforce each other in all sorts of ingenious ways. The couplet, the ordinary quatrain, the Omar Khayyam quatrain, terza rima, the rondeau, the rondel, the triolet, and all the stanza forms, are simply different schemes of combining rhythm and rhyme, the two fundamental formative devices of all poetry.

Like poetry, music welds its elements by means of two modes of arousing and fulfilling our expectations; but these, though they are somewhat analogous to poetic rhythm and rhyme, are so much less close to our ordinary experience that they will need a slightly more detailed explanation.

All modern music is divided up into beats, or equal time divisions, arranged into groups or measures by some regular system of accentuation. The accented beats, like the accented syllables in verse, impress the mind as goals of movement, in reference to which the light beats are felt as transitions or preparations. The regularity of the alternation of transition and goal is such that the mind quickly forms the habit of expecting each goal beforehand, and of taking a proportionate satisfaction in it when it arrives. This process of expectation and fulfillment links the successive beats together in an organism, which we may call the musical foot, after its analogy with the poetic foot.[25] So limited is the mental span that it is practically impossible for us to group more than three beats together in this way into a single organism; and all music consequently consists of combinations of either duple feet (one light beat followed by a heavy), or triple feet (two lights followed by a heavy) or complex arrangements of both sorts together. After this fundamental grouping of the time-elements is made, the mind instantly proceeds to recombine the groups into larger groups called phrases or sections. This it does by the same device of accentuation, either actual or ideal. It conceives one measure or foot as heavier or more significant than another, and so leaves one as a transition, to approach another as a goal. Thus groups of simple elements become themselves the compound elements of a larger synthesis, and the entire musical fabric gains definiteness and organization through the process of aroused and fulfilled expectation. Any metrical formula, like that of a bugle call, interrupted at any note before the last, gives us as vivid a sense of incompleteness as a statue with arms and legs broken off, or a ruined building, or a mutilated picture.

Metrical structure in music is thus, obviously enough, fairly analogous with metrical structure in verse, with its grouping of syllables into feet, of feet into verses, and of verses into couplets or stanzas. When we pass to the second sort of musical structure, however, which we may call tonal or harmonic structure, the parallel analogy with poetic rhyme is much less satisfactory. It is true that harmony and rhyme both act by presenting similar sounds at given points in the series of impressions; but harmony is a far more subtle, various, and potent organizing agent than rhyme. Harmony depends on the fact that the tones, or pitch elements, used in music, can be distinguished into unrestful and restful, or into transitional and final, just as the metrical or time-elements are. In primitive music, in which but one tone sounded at a time, the matter was almost absurdly simple: high notes were unrestful, because they involved muscular tension;[26] low notes were restful, because they meant relaxation of vocal effort. Consequently, a descent of the voice meant a transition to a goal, and songs were divided off into sections by successive falls of the voice or cadences. The word “cadence,” so important in musical terminology, preserves in itself the record of this phase of musical growth; from the Latin cado, to fall, it means primarily a sinking or lapsing, and hence, in general, a coming to rest.

As soon as two or more melodies were sounded together, however, the sense of rest following activity, the universal generator of design in a temporal series of impressions, could be produced in a far more subtle way. It could be produced by making the melodies pass through an inharmonious or dissonant chord or series of chords, to a harmonious one. As soon as dissonance came into general use, in other words, the sense of unrest, of impulsion toward something else, of progressive movement, that it imparted to music, was so potent that cadences could be made upward as well as downward; whenever dissonance resolved into consonance the effect of cadence ensued. And as dissonances are of all conceivable degrees of harshness, cadences could be made of any desired degree of finality. Moreover, as the tonal material of music grew more and more systematized, the feeling of key sprang up in men’s minds; all music was felt to be in a certain key, that is, grouped about a certain tone, the centre and goal of all the others; and then cadences came to have even greater variety in the degree of finality they seemed to assert, dependent not only on the strength of the dissonances they followed, but also on the remoteness or nearness of their final chord to the key-note of the piece. All this meant greater and greater resources for building up music into complex and yet perfectly definite organisms; and as harmonic form constantly interacted more and more subtly with metrical form the capacities of design became practically infinite.

Lest the reader get lost in the maze of technical details, however, it will be well now to revert to the general principles underlying all these musical phenomena, and to sum up, before passing on, the essential points we have been trying to come at. Those arts which, like poetry and music, present their matter to us in a temporal series, depend for that organization of variety into unity which is beauty (and the sine qua non of all art) on the arousal in us of expectations, which are presently fulfilled. By first leading us to expect something, and then presenting it, they enable us to group our impressions, to feel that they are interrelated and mutually dependent, to get, in short, the sense of design or order. Music effects this by means of metrical and harmonic form, which act is the same way so far as they present unrestful, followed by restful, impressions, though in different ways so far as the technical basis of these impressions is concerned. Psychologically speaking, metrical and harmonic form cooperate to give music definite structure in our minds; to reclaim it from the condition of a mere sensuous or emotional stimulus, and engraft upon it the final and supreme beauty of order.

All absolute or pure music depends for its structure on these two great formative agents of metrical and harmonic design; but the mode of their application progressed from simplicity to comparative complexity as music evolved from the choral song of the sixteenth century, out of which it grew, to the modern sonata and symphony. It would be quite impossible to examine in detail, here, all the stages of that progress. Our effort must be rather to define three well-marked phases of the many-sided growth in general and summary terms, taking for granted, meanwhile, the minor variations and modifications which elude our somewhat rough analysis. These three phases have in common certain essential traits. In each we see music making up its elementary units of effect, out of unorganized tones, by the aid of metrical and harmonic form; in each we see it combining these units into complex designs by means of the principles of variated repetition of them. The difference between the phases is that in the later ones the units are larger and more definite, and are combined into broader, more complex organisms.

The first phase is that in which short musical “subjects,” called motifs, are made the elements of contrapuntal forms such as the canon, free prelude, invention, madrigal, and fugue. This phase, in which pure music makes its first appearance, emerging from the choral music which needed no musical principles of design because it took its shape and meaning from words, grew naturally out of the choral music which preceded it. Imagine any bit of melody springing into existence in connection with a verbal phrase or sentence; then fancy it sounded without the words which gave it reason for being: it is easy to see that the only way it can now be given significance is by being made the subject of a musical design, that is, by being repeated, either literally or in modified form. Even the most primitive savages have always felt this. In Sir Hubert Parry’s book on “The Evolution of the Art of Music” we find many examples of formulas of notes used by savages as motifs, and developed simply by endless repetition. Such formulas as the following, for example, become, by mere repetition, true music of a primitive type:

[Listen]

The earliest attempts at pure music, though infinitely more advanced than these childish forms, were, like them, built up out of short motifs, of anywhere from two to a dozen tones, given definiteness by fixed metrical and harmonic relationships, and developed by means of repetition. All through the sixteenth and seventeenth centuries such contrapuntal forms were being developed to a high pitch of perfection, and they reached their culmination in the great fugues of J. S. Bach (1685-1750). Let us, then, instead of poring painfully over the obscure steps by which this vantage-point in art was reached, make a brief analysis of the consummated fugue-form, as it was treated by this supreme master.

The fugue of Bach, as it is represented, for example, in the forty-eight fugues of his “Well-Tempered Clavichord,” is a contrapuntal or polyphonic form; that is, it is made up of from two to five voices or parts, progressing with complete melodic independence of one another, yet in entire harmony. It is based on, or proceeds out of, a short motif or subject, often but a measure or two in length, but subjected to the most ingenious, varied, and exhaustive manipulation. It has certain structural divisions, and always ends in the key in which it began; yet its form does not, strictly speaking, depend on its sectional structure, as is the case with the song, dance, and sonata forms, but rather on the logical exploitation of the motif. The motif, in a word, is the primary fact of the fugue, the seed from which is germinated all the luxuriant florescent life of the subsequent music.

Since the motif is the animating force of the entire fugue, it is obvious that upon its pointedness, variety, and interest will depend the vitality of the composition as a whole. Bach accordingly spares no pains in the construction of his motifs. Much as they differ in length, expression, and style, all are brimful of interest. Each embodies some striking musical idea; some persuasive or emphatic rhythm, some definite tonal design which either by its oddness or by its utter naturalness and inevitability lays firm hold upon the attention at once, and coerces interest whenever it recurs. Here are a few motifs from the “Well-Tempered Clavichord”:

[Listen]

The variety is wonderful, even in these five subjects; and it will be seen at once how provocative of musical thought they are, like condensed aphorisms, packed with suggestions that send the mind questing through endless vistas of imagination.

As for the further treatment of the fugal motif, the actual formal rules, despite the awe they have immemorially aroused in the popular mind, are few and simple. After the first announcement of the subject by a single voice, it is answered by a second voice, at an interval of a fifth above;[27] then again stated by a third voice, and answered by a fourth. This process goes on until each voice has had a chance to enunciate the motif, after which the conversation goes on more freely; the subject is announced in divers keys, by divers voices; episodes, in a congruous style, vary the monotony; at last the subject is emphatically asserted by the various voices in quick succession (“stretto”) and with some little display or grandiloquence the piece comes to an end. But simple as is this scheme, it gives the composer ample opportunity to develop his theme with the utmost ingenuity, to subject it to the most surprising metamorphoses, and to place it in ever new lights and postures.

[Listen]

[Listen]

Practically all the possibilities of developing a motif were exploited by Bach in his marvelous fugues. The development of the motif means, in the most general terms, the repetition of it in forms sufficiently like the original one to be recognizable, yet sufficiently unlike it to be novel and interesting, to exhibit it, as has just been said, in “new lights and postures.” Now, since the identity of the motif depends on the fixed metrical and harmonic relations of its constituent tones, it is obvious that variation of it will have to consist in slight alterations of these metrical or of these harmonic relations, or of both, managed with such skill that they do in effect vary, without disintegrating, the motif. Our next task, then, will be to describe the chief means, both metrical and harmonic, by which the motif, in the hands of Bach and of all his successors, is modified without being destroyed.

Mere repetition, of course, is not, strictly speaking, development, however efficient it may be as a means of building up musical structures. With the repetition of the motif at a different place in the scale, however, such as is used in the “answer,” we have a true development, though an elementary one. Here all the metrical and harmonic relations of the motif are kept intact, at the same time that the bodily shifting of it in the scale throws upon it, so to speak, a new light. This will be felt at once by any musical person who will play over attentively the two subjects and answers of Figure VIII. A much more radical change is effected when the motif is changed from major to minor, or vice versa, or presented in some key other than the dominant and more remote, or presented with new harmonization. Still, even in such cases, the metrical and fundamental harmonic form of the subject remains unaltered.

In the device called “inversion,” much used by Bach, we have an essential change. The metrical form of the subject, remaining unchanged, ensures recognizability, but the harmonic relations, while remaining identical in respect of size, are exactly reversed in respect of direction; in other words, the subject is turned upside down. A few examples will explain this better than many words.

In Fugue VIII, Book I, W-T.C.,

[Listen]

becomes

[Listen]

In Fugue XX, Book I, W.-T.C.,

[Listen]

becomes

[Listen]

Many other examples might be given, for Bach is endlessly ingenious in his use of inversion, and all the composers who followed him have used it. Its effect, as will be seen from the examples, is most stimulating; the mind easily perceives the likeness to the original subject, since the rhythm is retained intact; yet the turning upside down of all the pitch relations produces most unexpected and interesting features.

So much for modifications dependent on altered tonal relationships. Those produced by metrical alterations are if anything even more serviceable to the composer. The simplest metrical change possible is produced by increasing or decreasing the actual duration of all the tones in the motif, while retaining jealously their proportionate duration. Thus the identity of the motif is not tampered with, but it is made to bear a new relation to its musical context. This device is named augmentation or diminution, according as the time-values of the motif are augmented or diminished.

In Fugue VIII, Book I, W.-T.C.,

[Listen]

becomes by augmentation,

[Listen]

In Fugue II, Book II, W.-T.C.,

[Listen]

is treated as follows:

[Listen]

In Fugue IX, Book II, W.-T.C.,

[Listen]

becomes by diminution,

[Listen]

It will be well worth the reader’s while to play through the entire fugues cited, noting the marvelous skill and subtlety with which Bach weaves his fabric.

In augmentation and diminution the original accents of the motif are for the most part retained—it is only the durations that are altered. More transformative still, therefore, are those devices which actually shift the accents of the motif, its most salient and identifying features. The most important of these, which we may call “shifted rhythm,” is seldom found in Bach; for its frequent and exhaustive application we must look to Mozart, Beethoven, and Brahms. As its name indicates, “shifted rhythm” consists in bodily shifting or transposing the motif in such a manner that its heavy beats become light, and its light ones heavy. In order to complete our account of the chief means of exploiting motifs, a few examples of shifted rhythm may find place here, even though they are not taken from Bach.

[Listen]

[Listen]

[Listen]

The foregoing discussion and examples will serve to give a slight idea of the wonderfully varied means of manipulating short motifs or musical subjects which composers derive from the peculiarities of metrical and harmonic organization. These means were utilized by Bach in the fugue with tireless industry and inexhaustible imagination. The fugue became in his hands the most perfect in its orderly complexity of all the forms of pure music; for sheer intellectual interest of a highly abstract kind his fugues have never been surpassed. Nor are they, as those unfamiliar with their intricacies are apt to suppose, devoid of emotional expression. The profundity, poignancy, and variety of the feeling they express are as marvelous as their consummate beauty of structure. They voice every mood, from the most earnest and impassioned gravity to the lightest banter. They are the first great independent monuments of pure music; and wherever future musicians may wander in the quest of new forms and new potencies of expression, Bach’s fugues will always stand magnificent on the horizon, marking the unassailable eastern heights from which pilgrimage was begun.

It is true, nevertheless, not only that the fugue form makes the severest demands on the attention and intelligence of the listener, but also that, because of its ecclesiastical origin and polyphonic style, it is incapable of the kind of highly personal, secular expression that it was in the spirit of the seventeenth century to demand. The prototypes of secular expression are the popular dance and song, and as soon as learned musicians had discovered means to give to dance and song movements the completeness, breadth, and organic coherence requisite to large beauty, they began to turn their attention away from the austere if noble contrapuntal forms, and to base their art on more popular models. The result was that even in the age of Bach the suite of dance and song movements began to be cultivated almost as sedulously as the fugue, and Bach himself wrote suites which in their way are quite as good as his more polyphonic works. The second great phase in the application to pure music of the principles of metrical and harmonic design is represented by the Suite.

As practiced by Bach, the suite is a series of dances and songs, written in a style partly polyphonic and partly monodic (that is, consisting of a single melody with subsidiary accompaniment). His introductory movements, allemandes in the French suites, preludes in the English, are stately or energetic contrapuntal pieces, intended to commence the suite with an impression of dignity. They are followed by courantes, bourrÉes, sarabandes, minuets, airs, and gavottes, all more or less definitely rhythmical and animated; and the concluding movement is generally a rollicking gigue. These suites of Bach may be considered perfect models of the form.

Now, when we contrast the suite with the fugue, the first difference that strikes us is that while the fugue, of polyphonic and ecclesiastical origin, is not definitely rhythmical, but proceeds somewhat amblingly and without division into segments of definite duration, the suite movements, owing their origin as they do either to songs intended to be sung to verses of equal length, or to dances intended to accompany symmetrical motions of the body, are markedly rhythmical—are made up, in fact, of phrases of equal length, balancing one another and giving an impression of complete symmetry. A fugue proceeds like a prose sentence; a gavotte or a bourrÉe or a minuet sounds more like a stanza of verses. In short, the fundamental element in a dance or song is not a fragmentary motif, but a complete phrase, filling, as a rule, two measures, though sometimes four, eight, or even three or five. The phrase begins with a motif, but fills it out with additional matter rounded off by some kind of cadence. That the phrase is thus a more complex and extended unit than the motif, a few examples from Bach will make clear.

[Listen]

[Listen]

It will be seen at once that in each case the second phrase answers or supplements the first. Like it in length and in general contour, it is at the same time more positive and final, so that the combined effect of the two is much like that of a couplet of verses. The first phrase, in fact, arouses in our minds an expectation, which only the second can satisfy; so that we have here a new and larger application of the now familiar device for binding together successive impressions. So characteristic is the supplementation of one phrase by another that theorists have adopted a set terminology suggested by it, calling the first phrase in all such cases the “antecedent phrase,” and the second the “consequent phrase.” It will also be noted, however, that the pair of phrases, once heard, becomes itself a unit in the mind, and arouses a new expectation of further matter to establish a still larger balance; and a reference to the pieces of Bach cited will show that Bach in each case follows up his pair of two-measure phrases by a four-measure phrase which supplements them as they supplemented each other. And so the process goes on, the piece growing ever larger and more complex by a regular accretion, until at last a phrase of definite and entire finality is reached, and the movement stands complete. All short songs and dances illustrate this progressive accretion of phrases into larger and larger units, by means of a constant unfolding of new expectations and fulfilments. To trace it out, to analyse what the composer has so ingeniously built up, is one of the most fascinating of studies; for it shows us how the simplest song is organic like a crystal, a flower, or an animal.

It is neither possible nor desirable to lay down here any rigid rules as to the metrical or harmonic relationships between the phrases. Generally, the metrical balance is fairly simple; a two-measure phrase is usually answered by another of the same length; two such phrases are often answered by a single four-measure phrase. But sometimes four measures are answered by two; and not infrequently three- or five-measure phrases appear unexpectedly but with quite satisfactory effect. The sense of balance must be given—that is all we can say: just how it shall be given will depend, as Mr. Weller would say, “on the taste and fancy of the composer.” As for the harmonic relationships, endless variety is possible. Yet we may here point out certain general principles. Every phrase, as we have seen, ends with some sort of a cadence, strong or weak according to the harshness of the dissonance it contains and the nearness of its final chord to the tonal centre, or key-note, of the piece. Now, as the salient tones of any key are its tonic and its dominant, the most obvious and natural course for the composer is to embody these in the successive phrases; and as the tonic conveys the impression of finality it is natural to use that last. A glance at Figure XII will show that Bach makes his antecedent phrase, in the first instance, end with a tonic chord, but a weak one; in the second instance, with a dominant. In both cases the consequent phrase ends with a strong tonic. Thus the harmonic as well as the metrical relations produce the effect of expectation and fulfilment, of antithesis between a transitive and a final impression. This is the general principle of all harmonic structure. The final impression is given by a strong tonic chord; the mediate impression, arousing the sense of anticipation, is given by some weaker and contrasting harmony, in the vast majority of cases the dominant chord. A full sense of the inexhaustible capabilities of this sort of harmonic structure can be gained only by a careful analysis of many pieces such as the movements of Bach’s suites. To this the reader is recommended.

When once composers had grasped the possibilities of structure by means of harmony, they quickly proceeded to work them out in the large, as applied to a complete musical form. They began to organize whole pieces by means of a grouping or ordered antithesis of different harmonic centres. Working without models and in the dark, they made many false starts and wrong moves, they tried many hybrid and unstable forms; but eventually, in the course of years of experiment, they developed two great types of structure, based on fundamental principles, and embodied, with unimportant minor modifications, in almost all the suite-movements of the seventeenth and of later centuries. The first of these two great general types of structure, called Binary Form, contained two distinct members or sections; the second, called Ternary Form, contained three sections.

The essential principle of binary form is the simplest conceivable. Every piece in binary form may be likened to a journey to a neighboring place, followed by a return home. “The King of France, with forty thousand men, marched up the hill, and then marched down again.” In the case of binary form, the king of France is the subject or theme of the piece; the forty thousand men are the variations or developments on this subject that are worked out as the piece proceeds; the hill is the progress from the tonic key to the contrasted tonal centre, generally the dominant, or, if the piece is in a minor key, its relative major; and the march down again is the return to the home key. More specifically, the first section begins with the announcement of the theme in the tonic key, and proceeds to ring changes upon it, meanwhile modulating to the contrasted key and ending with a firm and memorable cadence there. At this point the second section begins, with the theme as at first, but in the new instead of the original key; the modulation is reversed, the original key re-entered, and the same cadence already heard repeated, but now even more firmly, and with the added finality of the home key. The device is simplicity itself, yet it admits a surprising variety of detail within its perfectly obvious and satisfying unity of ultimate effect. Most of Bach’s allemandes, courantes, airs, sarabandes, and gigues, are executed in binary form.

The great disadvantage of this admirably concise and organic structure proved in the course of experience to be a certain monotony and rigidity. As movements became longer and more complex, the division into two sections, embodying but two keys in spite of momentary excursions to more remote centres, came to seem rather constricting. There was a dearth of variety about it, and a tendency to obviousness. The element of contrast, of adventure far afield, was somewhat lacking. Composers accordingly worked out, of course unconsciously, a more various but equally organic scheme of design—ternary form. In ternary form the first section is practically identical with that of binary form; but the second, instead of “marching down again,” makes the contrasting tonal centre it has reached but a starting-point for still further excursions. It modulates freely, using to the utmost the privilege of admission to all the keys of the gamut that music owes to Bach and his system of equal temperament; it plays with the theme, subjecting it to the modes of development we have already studied; it indulges in all sorts of pranks and whimsies, departing as much as possible from the set formality of the first section; in a word, it endeavors to establish a complete contrast with what has gone before, and while never violating logic, to get away as far as possible from the beaten track, from the rut of routine. Then, after this interregnum of variety, comes the third section with an emphatic reassertion of regularity, presenting once more the subject as at first, and in the tonic key, vindicating the unity of the movement of the whole, and rounding it out to orderly completeness. Splendid examples of this splendidly organic structure are most of the preludes, gavottes, bourrÉes, and minuets of Bach’s suites.

In the suite, then, as it was practiced by Bach and other seventeenth-century composers, we see operative a constantly broadening application of the use of expectation and fulfilment, in the interests of organic structure. Applying to artistic music those methods of metrical and harmonic form that had long determined the growth of folk-song and dance, the composers of this period gradually learned to make even wider and more intricate syntheses of their materials. So skilfully did they avail themselves of the relations between contrasting harmonic centres that they were able eventually to write whole movements as firmly organic, as deftly coordinated, as a vertebrate animal. By the ever-extending use of thematic variation and of free modulation, they made their pieces as various as they were systematic. And at last, in ternary form, they established that succession of statement, contrast, and reassertion, which seems even to-day the last word in the philosophy of general musical structure.

The gradual expansion and increase of complexity in the movements of the suite, made not only possible but logically necessary by the structural potencies of these great principles of statement, contrast, and reassertion, and of antithesis of keys, led eventually to a new phase of musical structure, the third and last in the evolution we have been tracing. The suite, in the seventeenth century the most successfully cultivated of all the forms of pure music, gave place in the eighteenth century to a still higher form, the sonata, which has held the position of supremacy ever since. The sonata form is, not only by tradition but by natural right, the norm of modern musical structure. Almost all the chief works of all the great composers from Haydn and Mozart to Brahms and TschaÏkowsky are cast in this mould, as we easily realize if we remember that not only those pieces specifically named “sonatas,” but also trios, quartets, quintets, and the like, and overtures and concertos and symphonies, are but pieces in sonata-form intended for various groups of instruments. The string quartet is a sonata for two violins, a viola, and a 'cello; the concerto is a sonata for solo instrument with orchestral accompaniment; and the symphony is a sonata on a large scale, for orchestra. This remarkable prevalence of a single type of structure in modern music means far more than the accidental survival, by inertia, of an artificial convention; it means that this type of structure is on the whole the best possible embodiment of variety and unity in tonal effects; that it is the natural outgrowth of more primitive forms; and that it is elastic enough to admit into its uniform scheme of order the most diverse expressions of individual temperaments and ideals. TschaÏkowsky’s intuition of beauty in tones is different enough from Haydn’s; and the formal medium of which both can avail themselves without violence to their genius must obviously be founded deep in universal human psychology.

The modern sonata consists, as a rule, of four movements, contrasted in character and in key, but combining to form a rational and complete whole. In expression, the movements conform deftly to the natural requirements of human nature. The first is energetic, vigorous, and complex. The second is sentimental, melancholy, noble, or profound. The third affords relief from the emotional concentration of the second; it is a dance, full of vivacity, humor, fantasy, and whimsical impulse; with Beethoven it becomes a consummate embodiment of the spirit of comedy, which is quite as essential a part of human nature as that of tragedy and earnest emotion. The fourth and last movement is again vigorous and dashing, but in a less intellectual way than the first; it ends the whole composition in a mood of simple and happy animation. As regards structure, moreover, the movements differ in conformity with the needs of the situation. The first, which is to be heard when the mind is most attentive and unfatigued, is by far the most complex,—is indeed often the only one in what is technically called “sonata-form.” The second, the interest of which is more emotional than intellectual, is usually of fairly primitive structure. The third, a dance, is in the simplest of ternary dance-forms, that of the minuet, and, as written by Haydn and Mozart, might almost be taken bodily out of a suite. The final movement is also usually of simple, obvious structure.

It is clear, then, that of all the movements of the sonata, the minuet is the nearest, in structure, to those more primitive types embodied in the suite.[28] It makes a link bridging the gap between the older form and its more highly-developed supplanter. A glance at its construction will show how near it is to those simple ternary forms already described in connection with the suite. The symphonic minuet of Haydn is built up out of phrases, welded together in the manner now so familiar to us.

[Listen]

But there is a considerable increase in the subtlety with which the phrases are combined, in the “modelling,” so to speak, of the melody. Greater variety is perceptible, the balance of the phrases is less obvious, while equally satisfactory. The structure, in the more extended sense, is ternary.[29] The first section of Haydn’s Minuet, just cited, ends, after eighteen measures, in the dominant key. The second section, or section of contrast, contains some passages that are markedly different from the original theme, though congruous with it, and modulates so far afield as E-flat major (the home key being G). After twenty-two measures of this digression, the section of reassertion enters with the original theme in the tonic key, lasts twenty-two measures, and ends strongly in the home key. The minuet proper, as with Bach, is followed by a similar short piece, called the trio, put in for the sake of contrast. After it the minuet recurs; and it is an interesting fact that the whole movement is thus a large example of the same device of statement, contrast, and reassertion that is exemplified in its parts. In other words, the whole minuet is a “statement,” the whole trio a “contrast,” and the repeated minuet a “reassertion.” We see here, then, the fundamental form which we described as ternary, and which may be symbolised by the letters A B A, utilized as a structural agent both in the individual parts, and in the whole of the movement. The symphonic minuet is quite obviously the child of the suite minuet, but a child approaching maturity, becoming complex and intricate in coordination.

The form generally adopted for the last movement of sonatas exemplifies a different way of utilizing the same general principles of design. As its name of “rondo” implies, it consists of a constant recurrence or “coming around” of the main thematic idea, which, as before, we may call A; but with several contrasting sections, instead of only one. The rondo type of structure may be symbolized by the letters A B A C A D A, etc. It embodies, obviously enough, a greater variety than the simpler dance form out of which it grew, and at the same time preserves unity by the repetition of the main theme. It is less perfectly coordinated, however, than the minuet; for as each episode occurs but once there is a deficiency of logic and of artistic economy; and as the principle of the form is sectional there is no intrinsic reason why it should not be prolonged indefinitely. It is, therefore, an essentially imperfect and indeterminate organism, although it is serviceable enough as the mould of a movement in which gaiety and general animation are more important than highly articulated plastic beauty.

The slow movement is of all the parts of the sonata the least uniform in structure. Often it is written in the primitive aria-form, identical with the minuet form; sometimes it is an adaptation of rondo form to the exigencies of deliberate movement and emotional eloquence; and not infrequently it is a modification of “first movement form,” or sonata form proper. Its value depends but little on its structure, and almost entirely on its expressive qualities.

Of all the movements of the sonata, as has already been said, the first, which comes when the listener is fresh and disposed to give minute and unflagging attention, is the most complex. First movement form, however, is but a further application of the simple principles of statement, contrast, and reassertion, and of contrast of keys, that are already operative, in an easily understood way, in the minuet, the aria, and the rondo. The first movement of a regular sonata begins with a first subject, or theme, in the tonic key, built, of course, upon a striking, individual, and memorable motif. After this has been well impressed upon the mind by a certain amount of repetition, either literal or modified, there is a formal transition to a contrasted key, generally the dominant, or, if the movement be in minor, the relative major, and a second subject enters, is in its turn well impressed upon the attention, and ends with an emphatic cadence or close in the contrasted key. This much makes up one complete section of the form. Historically, it is an outgrowth of the first part of an ordinary small ternary form, by simple magnification of the elements, and increasing definition of and contrast between them. What was at first but an inconspicuous modulation becomes a formal transition; and what was but a cadence in the contrasting key becomes a new subject, with its own individuality and function in the organism. And thus is built up the section of statement, with quite a high degree of complexity of its own. This is sometimes called the Exposition.

Next comes the “Free Fantasia” or “Working Out,” the section of contrast, derived from the similar section in the minuet, but far longer and more intricate. In material it is a development, or manipulation, of the thematic germs stated in the exposition, by aid of all the devices for developing motifs that we have traced. Structurally, its function is to establish complete contrast, to do away with the impression of rigid system that the first section is likely to engender, and in every possible way to give variety, surprise, and interest to the musical tissue. It is accordingly absolutely free in modulation, unsystematic in arrangement, and irregular in metrical division. In it the composer gives rein to his fancy, obeys the impulse of the moment, and lets his ingenuity rather than his shaping instinct determine his progress. Yet the section of contrast is not a mere limbo of chaotic impulses. It must have its own logic, it must be a true “development,” it must be throughout obviously founded on the themes already stated. There is no part of the sonata-form in which all the composer’s strength is more taxed than the Free Fantasia; here, indeed, freedom brings its own heavy responsibility.

After the contrast comes the reassertion, or “Reprise.” Having displayed his materials in every light his imagination can suggest, and having meanwhile almost obliterated his hearer’s sense of the key of the piece, the composer now carefully prepares to gather up all his flying threads, to stamp all this baffling variety with ultimate unity. Re-entering the home key, which has gained by its long silence a new power to delight and satisfy, he restates his two subjects or themes, in their original guise, but now both in the home key. As the essayist, after all his examples and figures and metaphors, returns to a bald, emphatic, final assertion of his thesis, the composer now, after all his playing with his ideas, reinstates them in more than their primitive simplicity.[30] To give them perfect finality he even reiterates them with fresh assertiveness, seems unwilling to leave them, and insists, in his Coda or tail-piece, that we take away with us a full sense of their import. Thus restatement, emphatic and prolonged, following upon contrast and digression, completes the unity of the whole composition, and closes the cycle to our satisfaction. It is impossible to conceive a type of musical structure which should better satisfy our demand for profusion of detail together with clarity of fundamental shape, than this highly perfected product of a long evolution, sonata-form.

It must not be supposed that this wonderful scheme of design reached its maturity in any short period of time, or through the labors of a few musicians. Infinitely slow and gradual was its growth; and though the immediate followers of J. S. Bach, and especially his own son, Philip Emmanuel Bach, brought it to a condition in which its general outline was pretty well established, it was still, at the time when Haydn appeared on the scene, incapable of that free manipulation which high musical beauty requires. It was Haydn who removed the last traces of stiffness and primitive angularity from the sonata-form; it was Haydn who brought it to complete definiteness as an artistic device and stamped it with lasting individuality; and it was Haydn who at least hinted and foreshadowed those subtleties and accommodations in its treatment which, as extended by Mozart and Beethoven, perfected its capabilities and brought it to its mature estate as the most vital, elastic and beautiful of modern musical forms.