Early in the narrator's life, he was known for his "docility" and "humanity" as well as his "tenderness," especially toward animals. These traits followed him into adulthood, and he found a wife who shared his love of animals and pets; they adopted a number of animals into their home, including a large and intelligent black cat named Pluto. Pluto was a personal favorite and would follow the narrator all over the house. They all share a lovely home surrounded by trees and green life.
However, the narrator admits that his character "experienced a radical alteration for the worse" as he grew moody and irritable and selfish: the result of apparent alcoholism. He became violent, even cutting out one of Pluto's eyes one night. Finally, the narrator says that he descended into the worst kind of spiritual "perverseness" and hanged the cat by the neck from a tree. He knew that he wanted only to "do wrong for the wrong's sake only" and that the cat had never done anything but to love him.
It is this very night that a fire burns down the narrator's whole house, and his "entire worldly wealth was swallowed up" just hours after he did a thing that he believed would "jeopardize [his] immortal soul" and "place it...even beyond the reach of the infinite mercy" of God. The fact that his entire estate is consumed by flames after he essentially commits his own soul to Hell seems as though it cannot be coincidence.
The narrator has long been abusive to his wife and his pets, and he purposely destroyed himself spiritually; as if to suggest that he can sink no lower in terms of his character, and his position in life declines as well. They are "compelled" to move into an "old building" as a result of their poverty, the result of the fire, and the narrator's next act of terror actually occurs in the basement—beneath the earth as Hell is thought, by some people, to be. It is as though he is symbolically moving closer to Hell with each despicable act he commits, and he knows it!
In this way, then, the movement in the story can certainly be symbolic of his mental and spiritual state.