What Do Poems Do?

It's hard to describe exactly what a great poem does. Here are some thoughts: 
  
"If I feel physically as if the top of my head were taken off, I know that is poetry."
--Emily Dickinson

"Energy within the poet goes into the poem, but then must go from the poem to a reader or listener. There has to be this transfer of energy."
—Muriel Rukeyser

"Imaginative work is not dropped like a pebble upon the ground; it is like a spider web attached ever so lightly, but attached to all four corners of the earth."
—Virginia Woolf

"Like a piece of ice on a hot stove, the poem must ride on its own melting."
—Robert Frost

"Truth is not an unveiling which destroys the secret, but a revelation that does it justice."
—Walter Benjamin