The context of a poem is likely to be only the poet's voice: a
voice speaking to no one in particular and unsupported by a
situation or character, as in a work of fiction. A sense of
itself is what the poem sponsors, and not a sense of the world.
It invents itself. Its necessity or urgency, its tone, its
mixture of meaning and sound are in the poet's voice. In such
isolation the poem engenders its authority.
-- Mark Strand. preface to Great American Poetry 1991.