With Rienzi, my intention was still only to write an “opera”; I sought out my materials to that end, and, concerned only with “operas,” I took them from finished poems, which had been fashioned, even as to their form, with artistic intent.  With The Flying Dutchman I entered upon a new path, in that I myself grew to be the artificer of a material that lay before me only in its simple, unelaborated outline as a folk saga.  From then on I was, in relation to all my dramatic works, first a poet; and only as I fully worked out the poem did I again become a musician.  However, I was a poet conscious beforehand of the expressive capacity to work out his poems musically; I had exercised this capacity to the point where I was fully aware of my ability to use it for the realization of a poetic intention; and not only could I rely with assurance on the aid of that capacity in drafting poetic sketches, but i could even, in that knowledge, shape the sketches in accordance with poetic necessity more freely than if I had shaped them expressly to be set to music.  Before [I reached this stage] I had to master the skill of musical expression, much as one learns a language.  But now I had thoroughly learnt the language of music; I had mastered it like a true mother tongue; and so I no longer needed to concern myself over formalities of expression in that which I had to set forth: [expression] stood at my command wholly as I required it, to communicate a particular view or sensation from inner necessity.  But that which is to be expressed in the language of music consists solely of emotions and sensations: [the language of music] expresses altogether, and in full measure, the emotional content of the elemental human language, independently of our word-language, which has become purely an informational tool.  That which, accordingly, remains inexpressible to absolute music is the precise identification of the emotion’s or sensation’s cause, through which they themselves attain greater definition; the necessary continuation and extension of the musical language’s range of expression consists, then in acquiring also the capacity to indicate with recognizable precision the individual, the particular; and this it acquires only by being wedded to the word-language.  But that union will only be successful when the musical language is linked primarily with that which is congenial and related to it in the word-language; the bond must occur exactly at that point in the word-language where an irresistible urge towards the expression of true, sensuous emotion make itself felt.  From what has been said, the content of that which must be expressed by the word and tone poet becomes self-evident: it is purely human, released from all convention.

Since, in the above-mentioned turning point in the direction of my art, I have been guided once and for all by my [poetic] material, specifically by material perceived through music’s eye, I could not, in shaping it, proceed otherwise than by gradually and totally abolishing, of necessity, the operatic form I had inherited.  This operatic form had never in itself been a definite form embracing the whole of the drama, but rather only an arbitrary conglomeration of single, shorter vocal forms which, in their quite accidental arrangement as arias, duets, trios, etc. with choruses and so-called ensemble pieces, actually went to make up the substance of operatic form.  In the poetic organization of my materials, I could not possibly any longer be concerned with filling up these ready-made forms, but only, and exclusively, with the emotionally-understood presentation of the drama’s subject taken as a whole.  In the entire course of the drama I saw no possibility of division or distinctions other than the acts, in which the place or the time, or the scenes, in which the characters themselves change.

As I drafted my scenes, I was not in the least constrained, by the nature of the material thus conceived, to have a care for any particular musical form in advance, for the scenes themselves dictated the musical working out as intrinsic and necessary to them.  With my ever-increasing sureness of perception in this regard, I could no longer even conceive of interrupting and inhibiting the spontaneous musical form emerging necessarily from the very nature of the scenes with arbitrary external accretions, with the violent implanting of conventional operatic vocal forms.  And so, I emphatically did not set out to destroy methodically - say, as a scheming modifier of forms - the aria, duet, or any other operatic form; instead, the omission of that form resulted quite spontaneously from the nature of the material.

Richard Wagner, Drei Operndichtungen nebst einer Mittheilung an seine Freunde (Leipzig, 1852), 143-52. Trans. Piero Wiess from Music in the Western World.