i respect and - of course - agree with the great Dylan Thomas
though
he seems to focus on a poem's affect on the greater world outside the poet
the poet's soul is changed forever as well - and - without the poet's change - the poem would not be written or spoken and none would hear the words
so
i would submit that the poet's soul changes in creating the poem - setting in motion a neverending and widening ripple in time - touching each reader as it goes from eye to neocortex to heartstring
funny thing - the poet's impetus - message - feelings - may have nothing to do with the readers' - since i believe we all take something different away from any poem - we make it our own - a communication - poet's soul to readers'
but then - i know so little - i likely know not what poetry is
thank you Philip for asking,
mikhail