(New to) Great Regulars: Williams' poem is effective because

of the implied reality. Give the reader a sensory experience to hold onto and you are halfway home. Convinced of the concrete actuality of an experience, your reader will be ready to make the leap to a metaphysical truth.

from A.S. Maulucci: Norwich Bulletin: On Poetry: Proof heightens sense of place

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They do not explain what those mysteries mean. What true poets do is capture some of this mystery. And true poets will be the first to honestly admit they don't know how they do it. Most likely it isn't deliberate. You get at the meaning indirectly.

from A.S. Maulucci: Norwich Bulletin: Poets don't have to be clever to convey meaning in work

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