All this development of instrumental music into territories more or less adjacent makes a very imposing show; and it is so markedly a product of the last generation that we easily over-estimate the novelty of its essential results. As I have said, instrumental music is more and more asking for external spurs to creative activity; but this does not mean that music as a whole is, so to speak, breaking loose from its moorings and adventurously voyaging on to uncharted seas. What it means is, simply, that, under the stress of modern culture, the barriers between vocal and instrumental, dramatic and non-dramatic, music have been to a great extent abolished. We may consider music as normally involving three persons: the composer, the performer, and the listener. Until the present generation, the role of the listener was normally quite passive. All that he had to do was to keep his ears open to the music, and further, when required, his ears open to words and his eyes to dramatic presentation. The composer and the performers did everything for him. But now they do not. The modern composer urges that, just as vocal music demands from the listener a separate knowledge of the words, so instrumental music may demand, as a condition of full understanding, a separate knowledge of some verbally expressible signification. The parallel no doubt holds well enough even if we answer, as we certainly may, that in much vocal music the words are so unimportant that it really does not musically matter if they are unintelligible or inaudible. But this latter-day demand on the listener is considerable. The listener to Strauss's _Don Quixote_, for example, must, in order to appreciate in full measure any section of this long work, have a fairly close acquaintance with Cervantes' book--whether derived from an analytical programme or from personal reading: there are neither words nor acting to give a clue, nor does the printed music itself give the slightest assistance, except in so far that a couple of themes are labelled with the names of the 'Knight of the sorrowful countenance' himself and Sancho Panza. Sometimes, no doubt, a composer helps at any rate the purchaser of his music more; but to the listener he gives nothing, and leaves his thought, as embodied in the mere title, to be reached as best it may. The modern composer makes these demands on the listener continually; and he does so simply because the sphere of the music-lover's imaginativeness and general culture has become so greatly enlarged that he thinks he can fairly afford to take the risk.