“The Snow Man” by Wallace Stevens 

I love “The Snow Man” by Wallace Stevens for its last line—“Nothing that is not there and the nothing that is”— and for breathtaking surprises along the way. It pretends to be about a child’s snowman, but Stevens slyly uses the impersonal “one”: snowman? human? Similarly, the first two stanzas pretend to be complete thoughts: “One must have a mind of winter/ To regard” etc. But in stanza 3, it’s suddenly clear these were merely hypotheses in a more complex thought: to regard x and to behold y, without thinking of z. In fact, the entire five-stanza poem is a single sentence, with masterful punctuation and line breaks. In its wonderful sonic quality and grammatical sleight of hand, it’s the work of a great American poet at the height of his craft.