Robert Frost's "Mending Wall" is about two different outlooks on life and relationships. The neighbors, one of whom is the speaker, meet each spring to mend the stone wall between their properties. The speaker wonders about why this ritual exists, since there is nothing that either of them has that could stray onto the other's land. There is no livestock on the one side that could damage the other's property. The speaker remarks only that “He is all pine and I am apple orchard." The neighbor, however, never questions the need for the fence. He has learned from his father that "Good fences make good neighbors."
The poem is a commentary on the artificial constructs that people build between themselves and the rest of the world. Even neighbors, those with whom we should be most comfortable and friendly, set themselves apart from one another. Though he has heard the neighbor's claim about good fences and good neighbors, the speaker doubts the truth of that sentiment. In lines 32-36 the speaker reveals his thoughts about fence building:
Before I built a wall I'd ask to know
What I was walling in or walling out,
And to whom I was like to give offense.
Something there is that doesn't love a wall,
That wants it down."
These lines clearly show that the speaker believes that something, likely nature itself, "wants [the fence] down, that fences are unnatural. Note how the speaker wonders about how walling in or out could "give offense." This pun is important. The word "offense" when spoken sounds almost exactly like the phrase "a fence." The speaker would think long and hard before intentionally creating either.
Yet, despite his reservations, he helps construct this wall between himself and his neighbor each spring. This act shows that even the speaker, who doesn't like offending fences, still is to blame, at least in part, for the division between him and his neighbor.
The last five lines of the poem show how the speakers share in building the wall has affected his view of his neighbor:
He moves in darkness as it seems to me,
Not of woods only and the shade of trees.
He will not go behind his father's saying,
And he likes having thought of it so well
He says again, "Good fences make good neighbours."
The neighbors repeated comment shows that these attitudes are learned, not natural. This social construct was built by his father, and he will keep the barrier in place. The speaker sees his neighbor as one who "moves in darkness." Darkness metaphorically can mean either lack of understanding or even something sinister. Either way the speaker means it, he is judging his neighbor. Either the neighbor is less wise or enlightened or he his more bound, by tradition or coldness, or both. Regardless of how the speaker means this thought, the very act of helping to mend the wall has affected him. He unwittingly becomes a part of the problem. His hesitance to speak helps to build the fence, and the offense.
For more information about the poem "Mending Wall," see the links below:
This is a truly genius poem. Each time I re-read it I see more. That is the mark of great poetry.