The second goal should be to complete the work both horizontally by filling in the gaps, and vertically by making the texture more complex, in order to achieve a continuous texture of sound consistent with the composer’s methods. This process of course needs to be done with discretion, but a certain degree of condign boldness is also required to obtain a sound which will make the sketched material from the composer sound authentic. Inspection of the sketches for Bruckner’s Eighth Symphony shows unpromising beginnings leading to magnificent results, as can be seen in the examples published in Dermot Gault’s important work The New Bruckner. The completer does not have the freedom that the composer had, but still the attempt needs to be made.
When the work is incomplete because of the composer’s retirement or death, as in the cases of the Schubert Tenth Symphony in D major, the Bruckner Ninth, the Mahler Tenth, the Elgar Third, and the Sibelius Eighth, and even Mozart’s Requiem and Bach’s Art of Fugue, one can be certain that the composer in finishing the work would have used quite a bit of innovation, going beyond the surviving material in ways difficult to predict. Whereas in considering Schubert’s unfinished piano sonatas and his Seventh and Eighth symphonies, one sees many complete works of more or less the same genre occurring both before and after the incomplete work, which makes completing the piece somewhat more secure. With Bruckner, familiarity with the other major works he produced while he was working on the Ninth, namely Psalm 150 and Helgoland, reveals quite a few very new and fruitful ideas; certainly the Ninth would have developed Bruckner’s gestural repertory even farther. Indeed, each movement of the Ninth shows innovative development. The first movement is the grandest Kopfsatz of them all, yet the mysterious and ominous opening subject is heard only once in the rest of the movement, in an enigmatic and difficult-to-hear canon at the beginning of the development. Surely, one would think, some more use could be made of this gripping music; perhaps that is the job of the completer of the finale. The compact yet complex Scherzo returns in length scale to the relatively short scherzo of the Seventh, yet it has harmonies, or the lack of them, that go far beyond those of the much larger scherzo of the Eighth. And there is that new fast trio in F sharp major, which amazingly uses a considerable amount of the sketch of an earlier slow trio in the same key with a viola solo. As for the adagio in E major and A flat major, what is one to make of a fifth part which begins with the second instead of the first theme? Five-part song form, which Bruckner had inherited from Beethoven and adapted for use in the quintet and six other symphonies, does not call for that, yet there it is, and the later brief but cataclysmic return of the first theme leads to a chord which contains nearly every note of the chromatic scale. If the finale is to go beyond those gestures, and in certain ways it most certainly must, any suggestion of innovation that Bruckner gives in the surviving fragments, whether apparent or buried, needs to be detected, recognized, conserved and developed with diligence.