Although there are relatively few major structural alterations in the autograph of Così fan tutte, there are numerous examples of small-scale changes which Mozart made as he polished his work. These included revisions made to enhance the dramatic effectiveness of the score as well as the purely musical detail of figuration and orchestration.

The Musical Representation of Drama

Mozart's concern with the effectiveness of the stage action in his operas is very apparent in his letters about Idomeneo. Once the structure of the plot, its detailed working out and the text itself had been agreed to his satisfaction, he set himself the objective of ensuring that his score enhanced the on-stage drama as effectively as possible. A significant category of revisions in the autograph score illustrate the musical dramatist at work.

One of the most powerful mechanisms for the musical expression of on-stage drama was the recall of which there are several well-known examples in the earlier Da Ponte operas. In introducing a musical recall to his score, Mozart's aim was instant recognition, almost always with a clear dramatic purpose in mind. The chorus ‘Bella vita militar’ sung as the two officers depart is recalled towards the end of the opera, where the repeat of its military strains shocks the two sisters by heralding the imminent return of their betrayed lovers. There are some indications that the decision to have this chorus performed twice in its original location was made at a late stage. Mozart indicated its repeat after the quintet ‘Di scrivermi’ with the instruction ‘attacca il coro’, the result of which, as noted in the NMA, is a 5/4 bar. The wording of this rubric, however, leaves some uncertainty as to whether the repeat of the chorus should be preceded by the twenty-five bar instrumental introduction heard on its first appearance. The additional words ‘da capo’ suggest the inclusion of the orchestral introduction, but these were smudged out. An assistant attempted to clarify matters with the further instruction: ‘NB qui si ripete il coro bella vita militar’, but again this left open the possibility that the repeat should omit the orchestral passage. In V1 there is much confusion at this point. A copyist wrote out the wind introduction followed by the chorus, but this introduction was apparently cut and reinstated several times.