"He moves in darkness as it seems to me,
Not of woods only and the shade of trees...."See in text(Text of the Poem)
The Swiss psychiatrist Carl Jung devised the concept of the human “shadow,” which refers to all the aspects of human nature of which an individual is unconscious. According to Jung’s account, each person represses a number of natural impulses and behaviours in order to exist within a family and a society. The stifled sides of human nature form one’s shadow. In this pair of lines, Frost’s narrator momentarily witnesses his neighbor’s shadow, characterized as a “darkness” and a wildness. As the imagery of the savage showed, the neighbour’s shadow side “doesn’t love [the] wall.” Yet the man builds the wall nonetheless.
"I'd ask to know
What I was walling in or walling out,..."See in text(Text of the Poem)
This question of what is being “wall[ed] in or wall[ed] out” is the central problem and theme of Frost’s poem. The wall serves not a physical purpose—“here there are no cows”—but rather a psychological purpose. The barrier represents both a walling in and a walling out. As the Austrian neurologist Sigmund Freud wrote, “the price of civilization is neurosis.” In other words, each human must “wall in” certain aspects of her own nature in order to participate in society. The result is a congenial “walling out” of the disagreeable aspects of others.
""Good fences make good neighbours."..."See in text(Text of the Poem)
“Good fences make good neighbours” is an English proverb which dates back to the 17th century. Frost’s poem, however, is largely responsible for its popularity today.