But if music implies form, it also implies con tent. It is a vehicle of expression no less than a way of arranging and organizing tones. When now we come to inquire into the processes which lie behind musical production, we find that they are various and highly complex. We shall, how ever, get an insight into their nature if we look upon music both as a means of conscious expression and as a medium of comnmnication. Regarded in this light, music takes its place be side gesture speech and writing. It differs from speech. however, in that it gives voice to feelings and emotions instead of to ideas. Speech is pri marily a medium for the communication of `thought? and when it attempts to express emo tion and sentiment borrows straightway from music—either rhythm (in taking poetic form) or melody (in constructing recitative or or it may go back to the common root of speech and music, and enrich itself from the language of gesture and mimetic movement. But while music's ultimate appeal is to the sensibilities, it cannot be said to exist apart from the intellect or the will. Such absolute disjunction could only rest on the fallacy that intellect, feeling, and volition are separable faculties of the mind. (See FACULTY.) Music arouses not only feeling, but also thought and action. The complex nature of the 'musical consciousness' is indicated by the fact that it is now called a feeling. now• an emo tion, now a perception, and now a sentiment. (See these words.) It is, indeed, all of these. The pleasurable feeling which music induces is unde niable: it arouses an emotion in the sense that it presents 'situations' which call forth organic sensations squarely faced by the attention; it includes the organization of auditory sensations into unitary perceptual wholes; and, filially, it involves sentiment by taking the form of the (esthetic judgment, e.g. 'these elements combined in this way are beautiful.' Nor does this ex haust the contents of musical expression. There may be, both in the motive of the artist and in the consciousness aroused in the hearer, imagina tions, retrospect ions, moods, desires, associations, resolves, and volitions. Thus far does the `rim sical consciousness' range. The key to its com plexity is furnished by a review of the large number of modes through which music appeals to consciousness. In the first place. simple tones have an affective value, which is different at different parts of the scale. Secondly, the simple clang or note varies not only. as we have seen, in sensational elements, but also in pleasantness and unpleasantness, as its clang-tint changes.
Thirdly. the same element of fusion which amalgamates the partials in the note is also present in the chord. Fourthly, the chord is also more or less pleasant. more or less conso nant or dissonant. Other elementary factors are the indefinite number of possible accentuations, of pitch sequences, repetitions, and alternations, of similarities and contrasts. Add to these the possibilities of modulation from key to key, the host of figures in each of which there is the charm of the like and the diverse, of symmetry and of complexity, and of unity maintaining it self in variety; add the employment of various instruments, including the human voice, and cen turies of experience lending their wealth of asso ciations, and the intricacies of musical composi tion and appreciation receive at least a partial explanation. The explanation cannot be com pleted except by a comprehensive account of the genesis and development of music. (See -ESTHET ICS; Music.) There are two or three stages in the evolution of music which deserve mention here on account of their psychological impor tance. The first is the production of the scale. It is very difficult for us to conceive what music would be without a definitely formulated scale. We have so constantly in mind the scale which has formed the basis of Western music for cen turies that it is almost impossible to appreciate the mental processes of people who have had music without a definite scale, or even of those whose scheme of intervals differs from ours. And yet, it is certain that a formulated scale fol lows upon musical practice. The scale came
from melodic utterances as rhythm came from the regular movements of the dance. We find in the music of savages informal and onsystematic vocal expressions of feeling which arc sometimes no more than intoned wails or howls, sometimes haphazard collections of simple figures repeated with little order or tinily. When these become definite enough to be remembered and to be re peated from time to time, material for the for mation of scales begins to collect; but, the scale as an abstract arrangement of musical intervals appears only at a comparatively late stage of intellectual progress. The nucleus of the scale was probably at first a single interval—an in terval which was agreeable and expressive. A comparison of various scales, Eastern and West ern, ancient and modern, points to the fifth and the fourth as the first intervals to be selected. Gradually other notes were added and two gen eral types of scales were formed: the pentatonic (scales based on five notes), in use in China, .Japan, Java, and the Pacific Islands, and the heptatonic (based on seven notes), the scales of India. Persia, Arabia. ancient Greece. and modern Europe. In all countries the octave seems to have been more or less explicitly recognized. The fact that most Caucasian races have produced seven-note systems, and the peoples of Eastern Asia five-note systems, indicates that the general structure of the scale depends ultimately upon artistic impulses which are common to a given type of mind. The attempt to derive the hepta tonic scale from an earlier, more primitive pen tatonic. seems to have failed. The two types ap pear to be equally primitive. Instruments giving a diatonic scale date as far back as the Stone Age. Doubtless, the choice of the interval of the semitone depends largely on the fact that the semitone is the smallest interval that the hu man voice can produce with ease and accuracy. Wallaschek, however, is of the opinion that the voice even with the aid of the ear would never have produced regular scales without help from musical instruments. Simplicity in construe Lion and use of instruments determined, he be lieves, the formation of the two great types of scales. Itut there is no reason why vocal utter ance itself should not have produced intervals of varying degrees of pleasantness and unpleas antness which would supply sufficient motive for the ehoice of a definite scale. The modes of Greek music furnish a good instance of scale construction upon a melodic basis: while our own major and minor scales illustrate the effect which harmony produces upon scale-making. The fact that the scale, as we have it now. was It thousand years in the making gives evidence at once of its evolutionary character and of its de pendence upon antecedent and contemporary mu sical practice. From a melodic system was grad ually developed the tonal sequence in which every note has its artistic functions in relation to every other note. This principle of tonality, relation of the various parts of the scale to the tonic, has had a gradual development 110 less than the selection of tones. Helmholtz remarks that primitive nixie, since it depends largely upon verbal expression to complete its meaning. has little need for tonality. This is true even in Greek and early Christian music. He argues that tonality is a purely ;esthetic product, which has been increasing up to modern times. The latest modification of our scale has been the introduc tion of regular chromatic intervals (represented by the black keys upon the piano). fur the pur poses of modulation and the assimilation of keys. It would require. however, a great number of extra notes to produce the pure diatonic scale on each note taken successively as tonic. Vari ous compromises have. therefore, been made by tempered intonation, in which the pure intervals are more or less modified. The present method of tuning in use among Western peoples is based upon the system of equal temperament, which di vides the scale into twelve equal parts, or semi tones. This system allows no perfectly pure interval except the octave, but is extremely simple and affords opportunity for varied musical expression.