Composers differ on this point: some are willing to change a poem as necessary in order to make a good art song, while others want to preserve the poem in making an art song. Poets need to know how they feel about having their poems changed in collaboration and make these feelings clear to the collaborator. It’s possible that the collaborator might not feel comfortable significantly altering a poem even if a poet is open to it.
While being flexible with one's poem helps, part of the issue is that collaborators may feel precious about the poem and resist altering it even when it is to the benefit of the collaboration that they not put the poem on a pedestal. I think about how poets can be proactive about making their collaborators feel like poems might be materials to be played with rather than well-wrought urns, as one critic put it.
Sometimes the rarified cultural pedestal on which a lot of people place poetry means that composers might hesitate to ask for changes. If you have a composer who understands that the poem is not set in stone and is instead as alive as you might feel it to be, then the possibilities can really open up in terms of a back and forth.
Live Poets Society
Composers often work with poets who are either dead or otherwise inaccessible (e.g. famous). This can lead to very different responses: some aren't used to asking for changes to the poem when the poet is alive (and may disagree), whereas other composers may feel tremendously free to change a poem having been used to working with poets who can’t protest changes (because they’ve been dead).
There is much to say about why composers tend to work with dead poets (e.g. prestige, intellectual property, funding structures), but these are topics unto themselves. What you're doing here--writing poems and collaborating, all while being alive--is already a major challenge to the way things have been done.
These are a few of the challenges of doing art song as a poetic collaborative practice, different from the norms by which we evaluate poems in other contexts (e.g. publishing lyric poems in magazines). Were we to collaborate with, say, visual artists, the points that I mention above would be different. As perhaps they should be. It’s when I work with artists who don’t identify as poets that I learn radically new ways of understanding my poetry.
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