Intro
Sometimes the New Critics illustrated big points with one tiny example. Like when Yvor Winters analyzed Robert Browning's poem in his book, In Defense of Reason—he didn't analyze the whole poem, he just concentrated on two lines.
Winters only needed the two lines though to make his point, you see. As he argued, the "precision of a word"—a.k.a., its exact meaning in context—cannot be understood from the word alone. You have to go looking at the words around it.
Keep in mind that nailing down the definition of one word, completely out of context, is complicated enough. Words, of course, carry with them both dictionary meanings (or denotation) and whole fuzzy fields of associations (or connotations). So when you combine words into sentences, all of their meanings start to play off each other giving you a much more complex overall impression of each individual word's meaning.
To illustrate this point, Winters used the following lines from Browning's "Serenade at the Villa."
Quote
So wore night; the East was gray,
White the broad-faced hemlock flowers.
Analysis
Winters argues for the importance of having both "wore" and "gray" in the same line:
The lines are marred by a crowding of long syllables and difficult consonants, but they have great beauty in spite of the fault. What I wish to point out, for the sake of my argument, is the relationship between the words wore and gray. The verb wore means literally that the night passed, but it carries with it connotations of exhaustion and attrition which belong to the condition of the protagonist; and grayness is a color which we associate with such a condition. If we change the phrase to read: 'Thus night passed' we shall have the same rational meaning, and a meter quite as respectable, but no trace of the power of the line: the connotation of wore will be lost, and the connotation of gray will remain merely in a state of ineffective potentiality […] [The poet] has to select words containing not only the right relationships within themselves, but the right relationships to each other.
According to Winters, "wore" and "gray" are powerful because their connotations harmonize. Together, they build a meaning that "thus night passed" just doesn't convey.
This is one of those close readings that lived well beyond Winters's book. In fact, Cleanth Brooks used Winters's reading in The Well Wrought Urn. Brooks argued against Winters; he gets all bristly over the part where Winters says that "So wore night" and "Thus night passed" have the same "rational meaning."
According to Brooks, all they have in common is the "lowest common denominator." The paraphrase of the poem is not actually part of the poem—it's something outside that we've tacked onto it. This might sound like a tiny technicality, but Brooks hated it when anyone summed up what a poem "really meant."
He believed that the meaning of a poem can only be understood by considering the poem as a whole. What's that? You wanted a lil' healthy, competitive controversy within the New Criticism movement? Your wish has been granted.